--- old/src/java.base/share/classes/java/lang/module/ModuleInfo.java	2016-12-15 09:19:28.188172233 +0000
+++ /dev/null	2016-12-10 08:16:53.177999985 +0000
@@ -1,899 +0,0 @@
-/*
- * Copyright (c) 2014, 2016, Oracle and/or its affiliates. All rights reserved.
- * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
- *
- * This code is free software; you can redistribute it and/or modify it
- * under the terms of the GNU General Public License version 2 only, as
- * published by the Free Software Foundation.  Oracle designates this
- * particular file as subject to the "Classpath" exception as provided
- * by Oracle in the LICENSE file that accompanied this code.
- *
- * This code is distributed in the hope that it will be useful, but WITHOUT
- * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
- * FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License
- * version 2 for more details (a copy is included in the LICENSE file that
- * accompanied this code).
- *
- * You should have received a copy of the GNU General Public License version
- * 2 along with this work; if not, write to the Free Software Foundation,
- * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA.
- *
- * Please contact Oracle, 500 Oracle Parkway, Redwood Shores, CA 94065 USA
- * or visit www.oracle.com if you need additional information or have any
- * questions.
- */
-
-package java.lang.module;
-
-import java.io.DataInput;
-import java.io.DataInputStream;
-import java.io.EOFException;
-import java.io.IOException;
-import java.io.InputStream;
-import java.io.UncheckedIOException;
-import java.lang.module.ModuleDescriptor.Builder;
-import java.lang.module.ModuleDescriptor.Requires;
-import java.lang.module.ModuleDescriptor.Exports;
-import java.lang.module.ModuleDescriptor.Opens;
-import java.nio.ByteBuffer;
-import java.nio.BufferUnderflowException;
-import java.util.ArrayList;
-import java.util.Collections;
-import java.util.HashMap;
-import java.util.HashSet;
-import java.util.List;
-import java.util.Map;
-import java.util.Set;
-import java.util.function.Supplier;
-
-import jdk.internal.module.ModuleHashes;
-
-import static jdk.internal.module.ClassFileConstants.*;
-
-
-/**
- * Read module information from a {@code module-info} class file.
- *
- * @implNote The rationale for the hand-coded reader is startup performance
- * and fine control over the throwing of InvalidModuleDescriptorException.
- */
-
-final class ModuleInfo {
-
-    // supplies the set of packages when ModulePackages attribute not present
-    private final Supplier<Set<String>> packageFinder;
-
-    // indicates if the ModuleHashes attribute should be parsed
-    private final boolean parseHashes;
-
-    private ModuleInfo(Supplier<Set<String>> pf, boolean ph) {
-        packageFinder = pf;
-        parseHashes = ph;
-    }
-
-    private ModuleInfo(Supplier<Set<String>> pf) {
-        this(pf, true);
-    }
-
-    /**
-     * Reads a {@code module-info.class} from the given input stream.
-     *
-     * @throws InvalidModuleDescriptorException
-     * @throws IOException
-     */
-    public static ModuleDescriptor read(InputStream in,
-                                        Supplier<Set<String>> pf)
-        throws IOException
-    {
-        try {
-            return new ModuleInfo(pf).doRead(new DataInputStream(in));
-        } catch (IllegalArgumentException | IllegalStateException e) {
-            throw invalidModuleDescriptor(e.getMessage());
-        } catch (EOFException x) {
-            throw truncatedModuleDescriptor();
-        }
-    }
-
-    /**
-     * Reads a {@code module-info.class} from the given byte buffer.
-     *
-     * @throws InvalidModuleDescriptorException
-     * @throws UncheckedIOException
-     */
-    public static ModuleDescriptor read(ByteBuffer bb,
-                                        Supplier<Set<String>> pf)
-    {
-        try {
-            return new ModuleInfo(pf).doRead(new DataInputWrapper(bb));
-        } catch (IllegalArgumentException | IllegalStateException e) {
-            throw invalidModuleDescriptor(e.getMessage());
-        } catch (EOFException x) {
-            throw truncatedModuleDescriptor();
-        } catch (IOException ioe) {
-            throw new UncheckedIOException(ioe);
-        }
-    }
-
-    /**
-     * Reads a {@code module-info.class} from the given byte buffer
-     * but ignore the {@code ModuleHashes} attribute.
-     *
-     * @throws InvalidModuleDescriptorException
-     * @throws UncheckedIOException
-     */
-    static ModuleDescriptor readIgnoringHashes(ByteBuffer bb,
-                                               Supplier<Set<String>> pf)
-    {
-        try {
-            return new ModuleInfo(pf, false).doRead(new DataInputWrapper(bb));
-        } catch (IllegalArgumentException | IllegalStateException e) {
-            throw invalidModuleDescriptor(e.getMessage());
-        } catch (EOFException x) {
-            throw truncatedModuleDescriptor();
-        } catch (IOException ioe) {
-            throw new UncheckedIOException(ioe);
-        }
-    }
-
-    /**
-     * Reads the input as a module-info class file.
-     *
-     * @throws IOException
-     * @throws InvalidModuleDescriptorException
-     * @throws IllegalArgumentException if thrown by the ModuleDescriptor.Builder
-     *         because an identifier is not a legal Java identifier, duplicate
-     *         exports, and many other reasons
-     */
-    private ModuleDescriptor doRead(DataInput in) throws IOException {
-
-        int magic = in.readInt();
-        if (magic != 0xCAFEBABE)
-            throw invalidModuleDescriptor("Bad magic number");
-
-        int minor_version = in.readUnsignedShort();
-        int major_version = in.readUnsignedShort();
-        if (major_version < 53) {
-            throw invalidModuleDescriptor("Must be >= 53.0");
-        }
-
-        ConstantPool cpool = new ConstantPool(in);
-
-        int access_flags = in.readUnsignedShort();
-        if (access_flags != ACC_MODULE)
-            throw invalidModuleDescriptor("access_flags should be ACC_MODULE");
-
-        int this_class = in.readUnsignedShort();
-        if (this_class != 0)
-            throw invalidModuleDescriptor("this_class must be 0");
-
-        int super_class = in.readUnsignedShort();
-        if (super_class > 0)
-            throw invalidModuleDescriptor("bad #super_class");
-
-        int interfaces_count = in.readUnsignedShort();
-        if (interfaces_count > 0)
-            throw invalidModuleDescriptor("Bad #interfaces");
-
-        int fields_count = in.readUnsignedShort();
-        if (fields_count > 0)
-            throw invalidModuleDescriptor("Bad #fields");
-
-        int methods_count = in.readUnsignedShort();
-        if (methods_count > 0)
-            throw invalidModuleDescriptor("Bad #methods");
-
-        int attributes_count = in.readUnsignedShort();
-
-        // the names of the attributes found in the class file
-        Set<String> attributes = new HashSet<>();
-
-        Builder builder = null;
-        Set<String> packages = null;
-        String version = null;
-        String mainClass = null;
-        String[] osValues = null;
-        ModuleHashes hashes = null;
-
-        for (int i = 0; i < attributes_count ; i++) {
-            int name_index = in.readUnsignedShort();
-            String attribute_name = cpool.getUtf8(name_index);
-            int length = in.readInt();
-
-            boolean added = attributes.add(attribute_name);
-            if (!added && isAttributeAtMostOnce(attribute_name)) {
-                throw invalidModuleDescriptor("More than one "
-                                              + attribute_name + " attribute");
-            }
-
-            switch (attribute_name) {
-
-                case MODULE :
-                    builder = readModuleAttribute(in, cpool);
-                    break;
-
-                case MODULE_PACKAGES :
-                    packages = readModulePackagesAttribute(in, cpool);
-                    break;
-
-                case MODULE_VERSION :
-                    version = readModuleVersionAttribute(in, cpool);
-                    break;
-
-                case MODULE_MAIN_CLASS :
-                    mainClass = readModuleMainClassAttribute(in, cpool);
-                    break;
-
-                case MODULE_TARGET :
-                    osValues = readModuleTargetAttribute(in, cpool);
-                    break;
-
-                case MODULE_HASHES :
-                    if (parseHashes) {
-                        hashes = readModuleHashesAttribute(in, cpool);
-                    } else {
-                        in.skipBytes(length);
-                    }
-                    break;
-
-                default:
-                    if (isAttributeDisallowed(attribute_name)) {
-                        throw invalidModuleDescriptor(attribute_name
-                                                      + " attribute not allowed");
-                    } else {
-                        in.skipBytes(length);
-                    }
-
-            }
-        }
-
-        // the Module attribute is required
-        if (builder == null) {
-            throw invalidModuleDescriptor(MODULE + " attribute not found");
-        }
-
-        // If the ModulePackages attribute is not present then the packageFinder
-        // is used to find the set of packages
-        boolean usedPackageFinder = false;
-        if (packages == null && packageFinder != null) {
-            try {
-                packages = new HashSet<>(packageFinder.get());
-            } catch (UncheckedIOException x) {
-                throw x.getCause();
-            }
-            usedPackageFinder = true;
-        }
-        if (packages != null) {
-            for (String pn : builder.exportedAndOpenPackages()) {
-                if (!packages.contains(pn)) {
-                    String tail;
-                    if (usedPackageFinder) {
-                        tail = " not found by package finder";
-                    } else {
-                        tail = " missing from ModulePackages attribute";
-                    }
-                    throw invalidModuleDescriptor("Package " + pn + tail);
-                }
-                packages.remove(pn);
-            }
-            builder.contains(packages);
-        }
-
-        if (version != null)
-            builder.version(version);
-        if (mainClass != null)
-            builder.mainClass(mainClass);
-        if (osValues != null) {
-            if (osValues[0] != null) builder.osName(osValues[0]);
-            if (osValues[1] != null) builder.osArch(osValues[1]);
-            if (osValues[2] != null) builder.osVersion(osValues[2]);
-        }
-        if (hashes != null)
-            builder.hashes(hashes);
-
-        return builder.build();
-    }
-
-    /**
-     * Reads the Module attribute, returning the ModuleDescriptor.Builder to
-     * build the corresponding ModuleDescriptor.
-     */
-    private Builder readModuleAttribute(DataInput in, ConstantPool cpool)
-        throws IOException
-    {
-        // module_name
-        int module_name_index = in.readUnsignedShort();
-        String mn = cpool.getUtf8AsBinaryName(module_name_index);
-
-        Builder builder = new ModuleDescriptor.Builder(mn, /*strict*/ false);
-
-        int module_flags = in.readUnsignedShort();
-        boolean open = ((module_flags & ACC_OPEN) != 0);
-        if (open)
-            builder.open(true);
-        if ((module_flags & ACC_SYNTHETIC) != 0)
-            builder.synthetic(true);
-
-        int requires_count = in.readUnsignedShort();
-        boolean requiresJavaBase = false;
-        for (int i=0; i<requires_count; i++) {
-            int index = in.readUnsignedShort();
-            int flags = in.readUnsignedShort();
-            String dn = cpool.getUtf8AsBinaryName(index);
-            Set<Requires.Modifier> mods;
-            if (flags == 0) {
-                mods = Collections.emptySet();
-            } else {
-                mods = new HashSet<>();
-                if ((flags & ACC_TRANSITIVE) != 0)
-                    mods.add(Requires.Modifier.TRANSITIVE);
-                if ((flags & ACC_STATIC_PHASE) != 0)
-                    mods.add(Requires.Modifier.STATIC);
-                if ((flags & ACC_SYNTHETIC) != 0)
-                    mods.add(Requires.Modifier.SYNTHETIC);
-                if ((flags & ACC_MANDATED) != 0)
-                    mods.add(Requires.Modifier.MANDATED);
-            }
-            builder.requires(mods, dn);
-            if (dn.equals("java.base"))
-                requiresJavaBase = true;
-        }
-        if (mn.equals("java.base")) {
-            if (requires_count > 0) {
-                throw invalidModuleDescriptor("The requires table for java.base"
-                                              + " must be 0 length");
-            }
-        } else if (!requiresJavaBase) {
-            throw invalidModuleDescriptor("The requires table must have"
-                                          + " an entry for java.base");
-        }
-
-        int exports_count = in.readUnsignedShort();
-        if (exports_count > 0) {
-            for (int i=0; i<exports_count; i++) {
-                int index = in.readUnsignedShort();
-                String pkg = cpool.getUtf8AsBinaryName(index);
-
-                Set<Exports.Modifier> mods;
-                int flags = in.readUnsignedShort();
-                if (flags == 0) {
-                    mods = Collections.emptySet();
-                } else {
-                    mods = new HashSet<>();
-                    if ((flags & ACC_SYNTHETIC) != 0)
-                        mods.add(Exports.Modifier.SYNTHETIC);
-                    if ((flags & ACC_MANDATED) != 0)
-                        mods.add(Exports.Modifier.MANDATED);
-                }
-
-                int exports_to_count = in.readUnsignedShort();
-                if (exports_to_count > 0) {
-                    Set<String> targets = new HashSet<>(exports_to_count);
-                    for (int j=0; j<exports_to_count; j++) {
-                        int exports_to_index = in.readUnsignedShort();
-                        targets.add(cpool.getUtf8AsBinaryName(exports_to_index));
-                    }
-                    builder.exports(mods, pkg, targets);
-                } else {
-                    builder.exports(mods, pkg);
-                }
-            }
-        }
-
-        int opens_count = in.readUnsignedShort();
-        if (opens_count > 0) {
-            if (open) {
-                throw invalidModuleDescriptor("The opens table for an open"
-                                              + " module must be 0 length");
-            }
-            for (int i=0; i<opens_count; i++) {
-                int index = in.readUnsignedShort();
-                String pkg = cpool.getUtf8AsBinaryName(index);
-
-                Set<Opens.Modifier> mods;
-                int flags = in.readUnsignedShort();
-                if (flags == 0) {
-                    mods = Collections.emptySet();
-                } else {
-                    mods = new HashSet<>();
-                    if ((flags & ACC_SYNTHETIC) != 0)
-                        mods.add(Opens.Modifier.SYNTHETIC);
-                    if ((flags & ACC_MANDATED) != 0)
-                        mods.add(Opens.Modifier.MANDATED);
-                }
-
-                int open_to_count = in.readUnsignedShort();
-                if (open_to_count > 0) {
-                    Set<String> targets = new HashSet<>(open_to_count);
-                    for (int j=0; j<open_to_count; j++) {
-                        int opens_to_index = in.readUnsignedShort();
-                        targets.add(cpool.getUtf8AsBinaryName(opens_to_index));
-                    }
-                    builder.opens(mods, pkg, targets);
-                } else {
-                    builder.opens(mods, pkg);
-                }
-            }
-        }
-
-        int uses_count = in.readUnsignedShort();
-        if (uses_count > 0) {
-            for (int i=0; i<uses_count; i++) {
-                int index = in.readUnsignedShort();
-                String sn = cpool.getClassNameAsBinaryName(index);
-                builder.uses(sn);
-            }
-        }
-
-        int provides_count = in.readUnsignedShort();
-        if (provides_count > 0) {
-            for (int i=0; i<provides_count; i++) {
-                int index = in.readUnsignedShort();
-                String sn = cpool.getClassNameAsBinaryName(index);
-                int with_count = in.readUnsignedShort();
-                List<String> providers = new ArrayList<>(with_count);
-                for (int j=0; j<with_count; j++) {
-                    index = in.readUnsignedShort();
-                    String pn = cpool.getClassNameAsBinaryName(index);
-                    providers.add(pn);
-                }
-                builder.provides(sn, providers);
-            }
-        }
-
-        return builder;
-    }
-
-    /**
-     * Reads the ModulePackages attribute
-     */
-    private Set<String> readModulePackagesAttribute(DataInput in, ConstantPool cpool)
-        throws IOException
-    {
-        int package_count = in.readUnsignedShort();
-        Set<String> packages = new HashSet<>(package_count);
-        for (int i=0; i<package_count; i++) {
-            int index = in.readUnsignedShort();
-            String pn = cpool.getUtf8AsBinaryName(index);
-            packages.add(pn);
-        }
-        return packages;
-    }
-
-    /**
-     * Reads the ModuleVersion attribute
-     */
-    private String readModuleVersionAttribute(DataInput in, ConstantPool cpool)
-        throws IOException
-    {
-        int index = in.readUnsignedShort();
-        return cpool.getUtf8(index);
-    }
-
-    /**
-     * Reads the ModuleMainClass attribute
-     */
-    private String readModuleMainClassAttribute(DataInput in, ConstantPool cpool)
-        throws IOException
-    {
-        int index = in.readUnsignedShort();
-        return cpool.getClassNameAsBinaryName(index);
-    }
-
-    /**
-     * Reads the ModuleTarget attribute
-     */
-    private String[] readModuleTargetAttribute(DataInput in, ConstantPool cpool)
-        throws IOException
-    {
-        String[] values = new String[3];
-
-        int name_index = in.readUnsignedShort();
-        if (name_index != 0)
-            values[0] = cpool.getUtf8(name_index);
-
-        int arch_index = in.readUnsignedShort();
-        if (arch_index != 0)
-            values[1] = cpool.getUtf8(arch_index);
-
-        int version_index = in.readUnsignedShort();
-        if (version_index != 0)
-            values[2] = cpool.getUtf8(version_index);
-
-        return values;
-    }
-
-
-    /**
-     * Reads the ModuleHashes attribute
-     */
-    private ModuleHashes readModuleHashesAttribute(DataInput in, ConstantPool cpool)
-        throws IOException
-    {
-        int algorithm_index = in.readUnsignedShort();
-        String algorithm = cpool.getUtf8(algorithm_index);
-
-        int hash_count = in.readUnsignedShort();
-        Map<String, byte[]> map = new HashMap<>(hash_count);
-        for (int i=0; i<hash_count; i++) {
-            int module_name_index = in.readUnsignedShort();
-            String mn = cpool.getUtf8AsBinaryName(module_name_index);
-            int hash_length = in.readUnsignedShort();
-            if (hash_length == 0) {
-                throw invalidModuleDescriptor("hash_length == 0");
-            }
-            byte[] hash = new byte[hash_length];
-            in.readFully(hash);
-            map.put(mn, hash);
-        }
-
-        return new ModuleHashes(algorithm, map);
-    }
-
-
-    /**
-     * Returns true if the given attribute can be present at most once
-     * in the class file. Returns false otherwise.
-     */
-    private static boolean isAttributeAtMostOnce(String name) {
-
-        if (name.equals(MODULE) ||
-                name.equals(SOURCE_FILE) ||
-                name.equals(SDE) ||
-                name.equals(MODULE_PACKAGES) ||
-                name.equals(MODULE_VERSION) ||
-                name.equals(MODULE_MAIN_CLASS) ||
-                name.equals(MODULE_TARGET) ||
-                name.equals(MODULE_HASHES))
-            return true;
-
-        return false;
-    }
-
-    /**
-     * Return true if the given attribute name is the name of a pre-defined
-     * attribute that is not allowed in the class file.
-     *
-     * Except for Module, InnerClasses, SourceFile, SourceDebugExtension, and
-     * Deprecated, none of the pre-defined attributes in JVMS 4.7 may appear.
-     */
-    private static boolean isAttributeDisallowed(String name) {
-        Set<String> notAllowed = predefinedNotAllowed;
-        if (notAllowed == null) {
-            notAllowed = Set.of(
-                    "ConstantValue",
-                    "Code",
-                    "StackMapTable",
-                    "Exceptions",
-                    "EnclosingMethod",
-                    "Signature",
-                    "LineNumberTable",
-                    "LocalVariableTable",
-                    "LocalVariableTypeTable",
-                    "RuntimeVisibleParameterAnnotations",
-                    "RuntimeInvisibleParameterAnnotations",
-                    "RuntimeVisibleTypeAnnotations",
-                    "RuntimeInvisibleTypeAnnotations",
-                    "Synthetic",
-                    "AnnotationDefault",
-                    "BootstrapMethods",
-                    "MethodParameters");
-            predefinedNotAllowed = notAllowed;
-        }
-        return notAllowed.contains(name);
-    }
-
-    // lazily created set the pre-defined attributes that are not allowed
-    private static volatile Set<String> predefinedNotAllowed;
-
-
-    /**
-     * The constant pool in a class file.
-     */
-    private static class ConstantPool {
-        static final int CONSTANT_Utf8 = 1;
-        static final int CONSTANT_Integer = 3;
-        static final int CONSTANT_Float = 4;
-        static final int CONSTANT_Long = 5;
-        static final int CONSTANT_Double = 6;
-        static final int CONSTANT_Class = 7;
-        static final int CONSTANT_String = 8;
-        static final int CONSTANT_Fieldref = 9;
-        static final int CONSTANT_Methodref = 10;
-        static final int CONSTANT_InterfaceMethodref = 11;
-        static final int CONSTANT_NameAndType = 12;
-        static final int CONSTANT_MethodHandle = 15;
-        static final int CONSTANT_MethodType = 16;
-        static final int CONSTANT_InvokeDynamic = 18;
-
-        private static class Entry {
-            protected Entry(int tag) {
-                this.tag = tag;
-            }
-            final int tag;
-        }
-
-        private static class IndexEntry extends Entry {
-            IndexEntry(int tag, int index) {
-                super(tag);
-                this.index = index;
-            }
-            final int index;
-        }
-
-        private static class Index2Entry extends Entry {
-            Index2Entry(int tag, int index1, int index2) {
-                super(tag);
-                this.index1 = index1;
-                this.index2 = index2;
-            }
-            final int index1,  index2;
-        }
-
-        private static class ValueEntry extends Entry {
-            ValueEntry(int tag, Object value) {
-                super(tag);
-                this.value = value;
-            }
-            final Object value;
-        }
-
-        final Entry[] pool;
-
-        ConstantPool(DataInput in) throws IOException {
-            int count = in.readUnsignedShort();
-            pool = new Entry[count];
-
-            for (int i = 1; i < count; i++) {
-                int tag = in.readUnsignedByte();
-                switch (tag) {
-
-                    case CONSTANT_Utf8:
-                        String svalue = in.readUTF();
-                        pool[i] = new ValueEntry(tag, svalue);
-                        break;
-
-                    case CONSTANT_Class:
-                    case CONSTANT_String:
-                        int index = in.readUnsignedShort();
-                        pool[i] = new IndexEntry(tag, index);
-                        break;
-
-                    case CONSTANT_Double:
-                        double dvalue = in.readDouble();
-                        pool[i] = new ValueEntry(tag, dvalue);
-                        i++;
-                        break;
-
-                    case CONSTANT_Fieldref:
-                    case CONSTANT_InterfaceMethodref:
-                    case CONSTANT_Methodref:
-                    case CONSTANT_InvokeDynamic:
-                    case CONSTANT_NameAndType:
-                        int index1 = in.readUnsignedShort();
-                        int index2 = in.readUnsignedShort();
-                        pool[i] = new Index2Entry(tag, index1, index2);
-                        break;
-
-                    case CONSTANT_MethodHandle:
-                        int refKind = in.readUnsignedByte();
-                        index = in.readUnsignedShort();
-                        pool[i] = new Index2Entry(tag, refKind, index);
-                        break;
-
-                    case CONSTANT_MethodType:
-                        index = in.readUnsignedShort();
-                        pool[i] = new IndexEntry(tag, index);
-                        break;
-
-                    case CONSTANT_Float:
-                        float fvalue = in.readFloat();
-                        pool[i] = new ValueEntry(tag, fvalue);
-                        break;
-
-                    case CONSTANT_Integer:
-                        int ivalue = in.readInt();
-                        pool[i] = new ValueEntry(tag, ivalue);
-                        break;
-
-                    case CONSTANT_Long:
-                        long lvalue = in.readLong();
-                        pool[i] = new ValueEntry(tag, lvalue);
-                        i++;
-                        break;
-
-                    default:
-                        throw invalidModuleDescriptor("Bad constant pool entry: "
-                                                      + i);
-                }
-            }
-        }
-
-        String getClassName(int index) {
-            checkIndex(index);
-            Entry e = pool[index];
-            if (e.tag != CONSTANT_Class) {
-                throw invalidModuleDescriptor("CONSTANT_Class expected at entry: "
-                                              + index);
-            }
-            return getUtf8(((IndexEntry) e).index);
-        }
-
-        String getClassNameAsBinaryName(int index) {
-            String value = getClassName(index);
-            return value.replace('/', '.');  // internal form -> binary name
-        }
-
-        String getUtf8(int index) {
-            checkIndex(index);
-            Entry e = pool[index];
-            if (e.tag != CONSTANT_Utf8) {
-                throw invalidModuleDescriptor("CONSTANT_Utf8 expected at entry: "
-                                              + index);
-            }
-            return (String) (((ValueEntry) e).value);
-        }
-
-        String getUtf8AsBinaryName(int index) {
-            String value = getUtf8(index);
-            return value.replace('/', '.');  // internal -> binary name
-        }
-
-        void checkIndex(int index) {
-            if (index < 1 || index >= pool.length)
-                throw invalidModuleDescriptor("Index into constant pool out of range");
-        }
-    }
-
-    /**
-     * A DataInput implementation that reads from a ByteBuffer.
-     */
-    private static class DataInputWrapper implements DataInput {
-        private final ByteBuffer bb;
-
-        DataInputWrapper(ByteBuffer bb) {
-            this.bb = bb;
-        }
-
-        @Override
-        public void readFully(byte b[]) throws IOException {
-            readFully(b, 0, b.length);
-        }
-
-        @Override
-        public void readFully(byte b[], int off, int len) throws IOException {
-            try {
-                bb.get(b, off, len);
-            } catch (BufferUnderflowException e) {
-                throw new EOFException(e.getMessage());
-            }
-        }
-
-        @Override
-        public int skipBytes(int n) {
-            int skip = Math.min(n, bb.remaining());
-            bb.position(bb.position() + skip);
-            return skip;
-        }
-
-        @Override
-        public boolean readBoolean() throws IOException {
-            try {
-                int ch = bb.get();
-                return (ch != 0);
-            } catch (BufferUnderflowException e) {
-                throw new EOFException(e.getMessage());
-            }
-        }
-
-        @Override
-        public byte readByte() throws IOException {
-            try {
-                return bb.get();
-            } catch (BufferUnderflowException e) {
-                throw new EOFException(e.getMessage());
-            }
-        }
-
-        @Override
-        public int readUnsignedByte() throws IOException {
-            try {
-                return ((int) bb.get()) & 0xff;
-            } catch (BufferUnderflowException e) {
-                throw new EOFException(e.getMessage());
-            }
-        }
-
-        @Override
-        public short readShort() throws IOException {
-            try {
-                return bb.getShort();
-            } catch (BufferUnderflowException e) {
-                throw new EOFException(e.getMessage());
-            }
-        }
-
-        @Override
-        public int readUnsignedShort() throws IOException {
-            try {
-                return ((int) bb.getShort()) & 0xffff;
-            } catch (BufferUnderflowException e) {
-                throw new EOFException(e.getMessage());
-            }
-        }
-
-        @Override
-        public char readChar() throws IOException {
-            try {
-                return bb.getChar();
-            } catch (BufferUnderflowException e) {
-                throw new EOFException(e.getMessage());
-            }
-        }
-
-        @Override
-        public int readInt() throws IOException {
-            try {
-                return bb.getInt();
-            } catch (BufferUnderflowException e) {
-                throw new EOFException(e.getMessage());
-            }
-        }
-
-        @Override
-        public long readLong() throws IOException {
-            try {
-                return bb.getLong();
-            } catch (BufferUnderflowException e) {
-                throw new EOFException(e.getMessage());
-            }
-        }
-
-        @Override
-        public float readFloat() throws IOException {
-            try {
-                return bb.getFloat();
-            } catch (BufferUnderflowException e) {
-                throw new EOFException(e.getMessage());
-            }
-        }
-
-        @Override
-        public double readDouble() throws IOException {
-            try {
-                return bb.getDouble();
-            } catch (BufferUnderflowException e) {
-                throw new EOFException(e.getMessage());
-            }
-        }
-
-        @Override
-        public String readLine() {
-            throw new RuntimeException("not implemented");
-        }
-
-        @Override
-        public String readUTF() throws IOException {
-            // ### Need to measure the performance and feasibility of using
-            // the UTF-8 decoder instead.
-            return DataInputStream.readUTF(this);
-        }
-    }
-
-    /**
-     * Returns an InvalidModuleDescriptorException with the given detail
-     * message
-     */
-    private static InvalidModuleDescriptorException
-    invalidModuleDescriptor(String msg) {
-        return new InvalidModuleDescriptorException(msg);
-    }
-
-    /**
-     * Returns an InvalidModuleDescriptorException with a detail message to
-     * indicate that the class file is truncated.
-     */
-    private static InvalidModuleDescriptorException truncatedModuleDescriptor() {
-        return invalidModuleDescriptor("Truncated module-info.class");
-    }
-
-}
--- /dev/null	2016-12-10 08:16:53.177999985 +0000
+++ new/src/java.base/share/classes/jdk/internal/module/ModuleInfo.java	2016-12-15 09:19:27.987158482 +0000
@@ -0,0 +1,1089 @@
+/*
+ * Copyright (c) 2014, 2016, Oracle and/or its affiliates. All rights reserved.
+ * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
+ *
+ * This code is free software; you can redistribute it and/or modify it
+ * under the terms of the GNU General Public License version 2 only, as
+ * published by the Free Software Foundation.  Oracle designates this
+ * particular file as subject to the "Classpath" exception as provided
+ * by Oracle in the LICENSE file that accompanied this code.
+ *
+ * This code is distributed in the hope that it will be useful, but WITHOUT
+ * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
+ * FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License
+ * version 2 for more details (a copy is included in the LICENSE file that
+ * accompanied this code).
+ *
+ * You should have received a copy of the GNU General Public License version
+ * 2 along with this work; if not, write to the Free Software Foundation,
+ * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA.
+ *
+ * Please contact Oracle, 500 Oracle Parkway, Redwood Shores, CA 94065 USA
+ * or visit www.oracle.com if you need additional information or have any
+ * questions.
+ */
+
+package jdk.internal.module;
+
+import java.io.DataInput;
+import java.io.DataInputStream;
+import java.io.EOFException;
+import java.io.IOException;
+import java.io.InputStream;
+import java.io.UncheckedIOException;
+import java.lang.module.InvalidModuleDescriptorException;
+import java.lang.module.ModuleDescriptor;
+import java.lang.module.ModuleDescriptor.Builder;
+import java.lang.module.ModuleDescriptor.Requires;
+import java.lang.module.ModuleDescriptor.Exports;
+import java.lang.module.ModuleDescriptor.Opens;
+import java.lang.module.ModuleDescriptor.Version;
+import java.nio.ByteBuffer;
+import java.nio.BufferUnderflowException;
+import java.util.ArrayList;
+import java.util.Collections;
+import java.util.HashMap;
+import java.util.HashSet;
+import java.util.List;
+import java.util.Map;
+import java.util.Set;
+import java.util.function.Supplier;
+
+import jdk.internal.misc.JavaLangModuleAccess;
+import jdk.internal.misc.SharedSecrets;
+import jdk.internal.module.ModuleResolution;
+
+import static jdk.internal.module.ClassFileConstants.*;
+
+
+/**
+ * Read module information from a {@code module-info} class file.
+ *
+ * @implNote The rationale for the hand-coded reader is startup performance
+ * and fine control over the throwing of InvalidModuleDescriptorException.
+ */
+
+public final class ModuleInfo {
+
+    private static final JavaLangModuleAccess JLMA
+        = SharedSecrets.getJavaLangModuleAccess();
+
+    // supplies the set of packages when ModulePackages attribute not present
+    private final Supplier<Set<String>> packageFinder;
+
+    // indicates if the ModuleHashes attribute should be parsed
+    private final boolean parseHashes;
+
+    private ModuleInfo(Supplier<Set<String>> pf, boolean ph) {
+        packageFinder = pf;
+        parseHashes = ph;
+    }
+
+    private ModuleInfo(Supplier<Set<String>> pf) {
+        this(pf, true);
+    }
+
+    /**
+     * A holder class for the ModuleDescriptor that is created by reading the
+     * Module and other standard class file attributes. It also holds the objects
+     * that represent the non-standard class file attributes that are read from
+     * the class file.
+     */
+    public static final class Attributes {
+        private final ModuleDescriptor descriptor;
+        private final ModuleHashes recordedHashes;
+        private final ModuleResolution moduleResolution;
+        Attributes(ModuleDescriptor descriptor,
+                   ModuleHashes recordedHashes,
+                   ModuleResolution moduleResolution) {
+            this.descriptor = descriptor;
+            this.recordedHashes = recordedHashes;
+            this.moduleResolution = moduleResolution;
+        }
+        public ModuleDescriptor descriptor() {
+            return descriptor;
+        }
+        public ModuleHashes recordedHashes() {
+            return recordedHashes;
+        }
+        public ModuleResolution moduleResolution() {
+            return moduleResolution;
+        }
+    }
+
+
+    /**
+     * Reads a {@code module-info.class} from the given input stream.
+     *
+     * @throws InvalidModuleDescriptorException
+     * @throws IOException
+     */
+    public static Attributes read(InputStream in, Supplier<Set<String>> pf)
+        throws IOException
+    {
+        try {
+            return new ModuleInfo(pf).doRead(new DataInputStream(in));
+        } catch (IllegalArgumentException | IllegalStateException e) {
+            throw invalidModuleDescriptor(e.getMessage());
+        } catch (EOFException x) {
+            throw truncatedModuleDescriptor();
+        }
+    }
+
+    /**
+     * Reads a {@code module-info.class} from the given byte buffer.
+     *
+     * @throws InvalidModuleDescriptorException
+     * @throws UncheckedIOException
+     */
+    public static Attributes read(ByteBuffer bb, Supplier<Set<String>> pf) {
+        try {
+            return new ModuleInfo(pf).doRead(new DataInputWrapper(bb));
+        } catch (IllegalArgumentException | IllegalStateException e) {
+            throw invalidModuleDescriptor(e.getMessage());
+        } catch (EOFException x) {
+            throw truncatedModuleDescriptor();
+        } catch (IOException ioe) {
+            throw new UncheckedIOException(ioe);
+        }
+    }
+
+    /**
+     * Reads a {@code module-info.class} from the given byte buffer
+     * but ignore the {@code ModuleHashes} attribute.
+     *
+     * @throws InvalidModuleDescriptorException
+     * @throws UncheckedIOException
+     */
+    public static Attributes readIgnoringHashes(ByteBuffer bb, Supplier<Set<String>> pf) {
+        try {
+            return new ModuleInfo(pf, false).doRead(new DataInputWrapper(bb));
+        } catch (IllegalArgumentException | IllegalStateException e) {
+            throw invalidModuleDescriptor(e.getMessage());
+        } catch (EOFException x) {
+            throw truncatedModuleDescriptor();
+        } catch (IOException ioe) {
+            throw new UncheckedIOException(ioe);
+        }
+    }
+
+    /**
+     * Reads the input as a module-info class file.
+     *
+     * @throws IOException
+     * @throws InvalidModuleDescriptorException
+     * @throws IllegalArgumentException if thrown by the ModuleDescriptor.Builder
+     *         because an identifier is not a legal Java identifier, duplicate
+     *         exports, and many other reasons
+     */
+    private Attributes doRead(DataInput in) throws IOException {
+
+        int magic = in.readInt();
+        if (magic != 0xCAFEBABE)
+            throw invalidModuleDescriptor("Bad magic number");
+
+        int minor_version = in.readUnsignedShort();
+        int major_version = in.readUnsignedShort();
+        if (major_version < 53) {
+            throw invalidModuleDescriptor("Must be >= 53.0");
+        }
+
+        ConstantPool cpool = new ConstantPool(in);
+
+        int access_flags = in.readUnsignedShort();
+        if (access_flags != ACC_MODULE)
+            throw invalidModuleDescriptor("access_flags should be ACC_MODULE");
+
+        int this_class = in.readUnsignedShort();
+        String mn = cpool.getClassName(this_class);
+        if (!"module-info".equals(mn))
+            throw invalidModuleDescriptor("this_class should be module-info");
+
+        int super_class = in.readUnsignedShort();
+        if (super_class > 0)
+            throw invalidModuleDescriptor("bad #super_class");
+
+        int interfaces_count = in.readUnsignedShort();
+        if (interfaces_count > 0)
+            throw invalidModuleDescriptor("Bad #interfaces");
+
+        int fields_count = in.readUnsignedShort();
+        if (fields_count > 0)
+            throw invalidModuleDescriptor("Bad #fields");
+
+        int methods_count = in.readUnsignedShort();
+        if (methods_count > 0)
+            throw invalidModuleDescriptor("Bad #methods");
+
+        int attributes_count = in.readUnsignedShort();
+
+        // the names of the attributes found in the class file
+        Set<String> attributes = new HashSet<>();
+
+        Builder builder = null;
+        Set<String> packages = null;
+        String mainClass = null;
+        String[] osValues = null;
+        ModuleHashes hashes = null;
+        ModuleResolution moduleResolution = null;
+
+        for (int i = 0; i < attributes_count ; i++) {
+            int name_index = in.readUnsignedShort();
+            String attribute_name = cpool.getUtf8(name_index);
+            int length = in.readInt();
+
+            boolean added = attributes.add(attribute_name);
+            if (!added && isAttributeAtMostOnce(attribute_name)) {
+                throw invalidModuleDescriptor("More than one "
+                                              + attribute_name + " attribute");
+            }
+
+            switch (attribute_name) {
+
+                case MODULE :
+                    builder = readModuleAttribute(in, cpool);
+                    break;
+
+                case MODULE_PACKAGES :
+                    packages = readModulePackagesAttribute(in, cpool);
+                    break;
+
+                case MODULE_MAIN_CLASS :
+                    mainClass = readModuleMainClassAttribute(in, cpool);
+                    break;
+
+                case MODULE_TARGET :
+                    osValues = readModuleTargetAttribute(in, cpool);
+                    break;
+
+                case MODULE_HASHES :
+                    if (parseHashes) {
+                        hashes = readModuleHashesAttribute(in, cpool);
+                    } else {
+                        in.skipBytes(length);
+                    }
+                    break;
+
+                case MODULE_RESOLUTION :
+                    moduleResolution = readModuleResolution(in, cpool);
+                    break;
+
+                default:
+                    if (isAttributeDisallowed(attribute_name)) {
+                        throw invalidModuleDescriptor(attribute_name
+                                                      + " attribute not allowed");
+                    } else {
+                        in.skipBytes(length);
+                    }
+
+            }
+        }
+
+        // the Module attribute is required
+        if (builder == null) {
+            throw invalidModuleDescriptor(MODULE + " attribute not found");
+        }
+
+        // If the ModulePackages attribute is not present then the packageFinder
+        // is used to find the set of packages
+        boolean usedPackageFinder = false;
+        if (packages == null && packageFinder != null) {
+            try {
+                packages = new HashSet<>(packageFinder.get());
+            } catch (UncheckedIOException x) {
+                throw x.getCause();
+            }
+            usedPackageFinder = true;
+        }
+        if (packages != null) {
+            Set<String> exportedPackages = JLMA.exportedPackages(builder);
+            Set<String> openPackages = JLMA.openPackages(builder);
+            if (packages.containsAll(exportedPackages)
+                    && packages.containsAll(openPackages)) {
+                packages.removeAll(exportedPackages);
+                packages.removeAll(openPackages);
+            } else {
+                // the set of packages is not complete
+                Set<String> exportedAndOpenPackages = new HashSet<>();
+                exportedAndOpenPackages.addAll(exportedPackages);
+                exportedAndOpenPackages.addAll(openPackages);
+                for (String pn : exportedAndOpenPackages) {
+                    if (!packages.contains(pn)) {
+                        String tail;
+                        if (usedPackageFinder) {
+                            tail = " not found by package finder";
+                        } else {
+                            tail = " missing from ModulePackages attribute";
+                        }
+                        throw invalidModuleDescriptor("Package " + pn + tail);
+                    }
+                }
+                assert false; // should not get here
+            }
+            builder.contains(packages);
+        }
+
+        if (mainClass != null)
+            builder.mainClass(mainClass);
+        if (osValues != null) {
+            if (osValues[0] != null) builder.osName(osValues[0]);
+            if (osValues[1] != null) builder.osArch(osValues[1]);
+            if (osValues[2] != null) builder.osVersion(osValues[2]);
+        }
+
+        ModuleDescriptor descriptor = builder.build();
+        return new Attributes(descriptor, hashes, moduleResolution);
+    }
+
+    /**
+     * Reads the Module attribute, returning the ModuleDescriptor.Builder to
+     * build the corresponding ModuleDescriptor.
+     */
+    private Builder readModuleAttribute(DataInput in, ConstantPool cpool)
+        throws IOException
+    {
+        // module_name
+        int module_name_index = in.readUnsignedShort();
+        String mn = cpool.getModuleName(module_name_index);
+
+        int module_flags = in.readUnsignedShort();
+        boolean open = ((module_flags & ACC_OPEN) != 0);
+        boolean synthetic = ((module_flags & ACC_SYNTHETIC) != 0);
+
+        Builder builder = JLMA.newModuleBuilder(mn, false, open, synthetic);
+
+        int module_version_index = in.readUnsignedShort();
+        if (module_version_index != 0) {
+            String vs = cpool.getUtf8(module_version_index);
+            builder.version(vs);
+        }
+
+        int requires_count = in.readUnsignedShort();
+        boolean requiresJavaBase = false;
+        for (int i=0; i<requires_count; i++) {
+            int requires_index = in.readUnsignedShort();
+            String dn = cpool.getModuleName(requires_index);
+
+            int requires_flags = in.readUnsignedShort();
+            Set<Requires.Modifier> mods;
+            if (requires_flags == 0) {
+                mods = Collections.emptySet();
+            } else {
+                mods = new HashSet<>();
+                if ((requires_flags & ACC_TRANSITIVE) != 0)
+                    mods.add(Requires.Modifier.TRANSITIVE);
+                if ((requires_flags & ACC_STATIC_PHASE) != 0)
+                    mods.add(Requires.Modifier.STATIC);
+                if ((requires_flags & ACC_SYNTHETIC) != 0)
+                    mods.add(Requires.Modifier.SYNTHETIC);
+                if ((requires_flags & ACC_MANDATED) != 0)
+                    mods.add(Requires.Modifier.MANDATED);
+            }
+
+            int requires_version_index = in.readUnsignedShort();
+            Version compiledVersion = null;
+            if (requires_version_index != 0) {
+                String vs = cpool.getUtf8(requires_version_index);
+                compiledVersion = Version.parse(vs);
+            }
+
+            if (compiledVersion == null) {
+                builder.requires(mods, dn);
+            } else {
+                builder.requires(mods, dn, compiledVersion);
+            }
+
+            if (dn.equals("java.base"))
+                requiresJavaBase = true;
+        }
+        if (mn.equals("java.base")) {
+            if (requires_count > 0) {
+                throw invalidModuleDescriptor("The requires table for java.base"
+                                              + " must be 0 length");
+            }
+        } else if (!requiresJavaBase) {
+            throw invalidModuleDescriptor("The requires table must have"
+                                          + " an entry for java.base");
+        }
+
+        int exports_count = in.readUnsignedShort();
+        if (exports_count > 0) {
+            for (int i=0; i<exports_count; i++) {
+                int exports_index = in.readUnsignedShort();
+                String pkg = cpool.getPackageName(exports_index);
+
+                Set<Exports.Modifier> mods;
+                int exports_flags = in.readUnsignedShort();
+                if (exports_flags == 0) {
+                    mods = Collections.emptySet();
+                } else {
+                    mods = new HashSet<>();
+                    if ((exports_flags & ACC_SYNTHETIC) != 0)
+                        mods.add(Exports.Modifier.SYNTHETIC);
+                    if ((exports_flags & ACC_MANDATED) != 0)
+                        mods.add(Exports.Modifier.MANDATED);
+                }
+
+                int exports_to_count = in.readUnsignedShort();
+                if (exports_to_count > 0) {
+                    Set<String> targets = new HashSet<>(exports_to_count);
+                    for (int j=0; j<exports_to_count; j++) {
+                        int exports_to_index = in.readUnsignedShort();
+                        targets.add(cpool.getModuleName(exports_to_index));
+                    }
+                    builder.exports(mods, pkg, targets);
+                } else {
+                    builder.exports(mods, pkg);
+                }
+            }
+        }
+
+        int opens_count = in.readUnsignedShort();
+        if (opens_count > 0) {
+            if (open) {
+                throw invalidModuleDescriptor("The opens table for an open"
+                                              + " module must be 0 length");
+            }
+            for (int i=0; i<opens_count; i++) {
+                int opens_index = in.readUnsignedShort();
+                String pkg = cpool.getPackageName(opens_index);
+
+                Set<Opens.Modifier> mods;
+                int opens_flags = in.readUnsignedShort();
+                if (opens_flags == 0) {
+                    mods = Collections.emptySet();
+                } else {
+                    mods = new HashSet<>();
+                    if ((opens_flags & ACC_SYNTHETIC) != 0)
+                        mods.add(Opens.Modifier.SYNTHETIC);
+                    if ((opens_flags & ACC_MANDATED) != 0)
+                        mods.add(Opens.Modifier.MANDATED);
+                }
+
+                int open_to_count = in.readUnsignedShort();
+                if (open_to_count > 0) {
+                    Set<String> targets = new HashSet<>(open_to_count);
+                    for (int j=0; j<open_to_count; j++) {
+                        int opens_to_index = in.readUnsignedShort();
+                        targets.add(cpool.getModuleName(opens_to_index));
+                    }
+                    builder.opens(mods, pkg, targets);
+                } else {
+                    builder.opens(mods, pkg);
+                }
+            }
+        }
+
+        int uses_count = in.readUnsignedShort();
+        if (uses_count > 0) {
+            for (int i=0; i<uses_count; i++) {
+                int index = in.readUnsignedShort();
+                String sn = cpool.getClassName(index);
+                builder.uses(sn);
+            }
+        }
+
+        int provides_count = in.readUnsignedShort();
+        if (provides_count > 0) {
+            for (int i=0; i<provides_count; i++) {
+                int index = in.readUnsignedShort();
+                String sn = cpool.getClassName(index);
+                int with_count = in.readUnsignedShort();
+                List<String> providers = new ArrayList<>(with_count);
+                for (int j=0; j<with_count; j++) {
+                    index = in.readUnsignedShort();
+                    String pn = cpool.getClassName(index);
+                    providers.add(pn);
+                }
+                builder.provides(sn, providers);
+            }
+        }
+
+        return builder;
+    }
+
+    /**
+     * Reads the ModulePackages attribute
+     */
+    private Set<String> readModulePackagesAttribute(DataInput in, ConstantPool cpool)
+        throws IOException
+    {
+        int package_count = in.readUnsignedShort();
+        Set<String> packages = new HashSet<>(package_count);
+        for (int i=0; i<package_count; i++) {
+            int index = in.readUnsignedShort();
+            String pn = cpool.getPackageName(index);
+            boolean added = packages.add(pn);
+            if (!added) {
+                throw invalidModuleDescriptor("Package " + pn + " in ModulePackages"
+                                              + "attribute more than once");
+            }
+        }
+        return packages;
+    }
+
+    /**
+     * Reads the ModuleMainClass attribute
+     */
+    private String readModuleMainClassAttribute(DataInput in, ConstantPool cpool)
+        throws IOException
+    {
+        int index = in.readUnsignedShort();
+        return cpool.getClassName(index);
+    }
+
+    /**
+     * Reads the ModuleTarget attribute
+     */
+    private String[] readModuleTargetAttribute(DataInput in, ConstantPool cpool)
+        throws IOException
+    {
+        String[] values = new String[3];
+
+        int name_index = in.readUnsignedShort();
+        if (name_index != 0)
+            values[0] = cpool.getUtf8(name_index);
+
+        int arch_index = in.readUnsignedShort();
+        if (arch_index != 0)
+            values[1] = cpool.getUtf8(arch_index);
+
+        int version_index = in.readUnsignedShort();
+        if (version_index != 0)
+            values[2] = cpool.getUtf8(version_index);
+
+        return values;
+    }
+
+
+    /**
+     * Reads the ModuleHashes attribute
+     */
+    private ModuleHashes readModuleHashesAttribute(DataInput in, ConstantPool cpool)
+        throws IOException
+    {
+        int algorithm_index = in.readUnsignedShort();
+        String algorithm = cpool.getUtf8(algorithm_index);
+
+        int hash_count = in.readUnsignedShort();
+        Map<String, byte[]> map = new HashMap<>(hash_count);
+        for (int i=0; i<hash_count; i++) {
+            int module_name_index = in.readUnsignedShort();
+            String mn = cpool.getModuleName(module_name_index);
+            int hash_length = in.readUnsignedShort();
+            if (hash_length == 0) {
+                throw invalidModuleDescriptor("hash_length == 0");
+            }
+            byte[] hash = new byte[hash_length];
+            in.readFully(hash);
+            map.put(mn, hash);
+        }
+
+        return new ModuleHashes(algorithm, map);
+    }
+
+    /**
+     * Reads the ModuleResolution attribute.
+     */
+    private ModuleResolution readModuleResolution(DataInput in,
+                                                  ConstantPool cpool)
+        throws IOException
+    {
+        int flags = in.readUnsignedShort();
+
+        int reason = 0;
+        if ((flags & WARN_DEPRECATED) != 0)
+            reason = WARN_DEPRECATED;
+        if ((flags & WARN_DEPRECATED_FOR_REMOVAL) != 0) {
+            if (reason != 0)
+                throw invalidModuleDescriptor("Bad module resolution flags:" + flags);
+            reason = WARN_DEPRECATED_FOR_REMOVAL;
+        }
+        if ((flags & WARN_INCUBATING) != 0) {
+            if (reason != 0)
+                throw invalidModuleDescriptor("Bad module resolution flags:" + flags);
+        }
+
+        return new ModuleResolution(flags);
+    }
+
+
+    /**
+     * Returns true if the given attribute can be present at most once
+     * in the class file. Returns false otherwise.
+     */
+    private static boolean isAttributeAtMostOnce(String name) {
+
+        if (name.equals(MODULE) ||
+                name.equals(SOURCE_FILE) ||
+                name.equals(SDE) ||
+                name.equals(MODULE_PACKAGES) ||
+                name.equals(MODULE_MAIN_CLASS) ||
+                name.equals(MODULE_TARGET) ||
+                name.equals(MODULE_HASHES) ||
+                name.equals(MODULE_RESOLUTION))
+            return true;
+
+        return false;
+    }
+
+    /**
+     * Return true if the given attribute name is the name of a pre-defined
+     * attribute that is not allowed in the class file.
+     *
+     * Except for Module, InnerClasses, SourceFile, SourceDebugExtension, and
+     * Deprecated, none of the pre-defined attributes in JVMS 4.7 may appear.
+     */
+    private static boolean isAttributeDisallowed(String name) {
+        Set<String> notAllowed = predefinedNotAllowed;
+        if (notAllowed == null) {
+            notAllowed = Set.of(
+                    "ConstantValue",
+                    "Code",
+                    "StackMapTable",
+                    "Exceptions",
+                    "EnclosingMethod",
+                    "Signature",
+                    "LineNumberTable",
+                    "LocalVariableTable",
+                    "LocalVariableTypeTable",
+                    "RuntimeVisibleParameterAnnotations",
+                    "RuntimeInvisibleParameterAnnotations",
+                    "RuntimeVisibleTypeAnnotations",
+                    "RuntimeInvisibleTypeAnnotations",
+                    "Synthetic",
+                    "AnnotationDefault",
+                    "BootstrapMethods",
+                    "MethodParameters");
+            predefinedNotAllowed = notAllowed;
+        }
+        return notAllowed.contains(name);
+    }
+
+    // lazily created set the pre-defined attributes that are not allowed
+    private static volatile Set<String> predefinedNotAllowed;
+
+
+    /**
+     * The constant pool in a class file.
+     */
+    private static class ConstantPool {
+        static final int CONSTANT_Utf8 = 1;
+        static final int CONSTANT_Integer = 3;
+        static final int CONSTANT_Float = 4;
+        static final int CONSTANT_Long = 5;
+        static final int CONSTANT_Double = 6;
+        static final int CONSTANT_Class = 7;
+        static final int CONSTANT_String = 8;
+        static final int CONSTANT_Fieldref = 9;
+        static final int CONSTANT_Methodref = 10;
+        static final int CONSTANT_InterfaceMethodref = 11;
+        static final int CONSTANT_NameAndType = 12;
+        static final int CONSTANT_MethodHandle = 15;
+        static final int CONSTANT_MethodType = 16;
+        static final int CONSTANT_InvokeDynamic = 18;
+        static final int CONSTANT_Module = 19;
+        static final int CONSTANT_Package = 20;
+
+        private static class Entry {
+            protected Entry(int tag) {
+                this.tag = tag;
+            }
+            final int tag;
+        }
+
+        private static class IndexEntry extends Entry {
+            IndexEntry(int tag, int index) {
+                super(tag);
+                this.index = index;
+            }
+            final int index;
+        }
+
+        private static class Index2Entry extends Entry {
+            Index2Entry(int tag, int index1, int index2) {
+                super(tag);
+                this.index1 = index1;
+                this.index2 = index2;
+            }
+            final int index1,  index2;
+        }
+
+        private static class ValueEntry extends Entry {
+            ValueEntry(int tag, Object value) {
+                super(tag);
+                this.value = value;
+            }
+            final Object value;
+        }
+
+        final Entry[] pool;
+
+        ConstantPool(DataInput in) throws IOException {
+            int count = in.readUnsignedShort();
+            pool = new Entry[count];
+
+            for (int i = 1; i < count; i++) {
+                int tag = in.readUnsignedByte();
+                switch (tag) {
+
+                    case CONSTANT_Utf8:
+                        String svalue = in.readUTF();
+                        pool[i] = new ValueEntry(tag, svalue);
+                        break;
+
+                    case CONSTANT_Class:
+                    case CONSTANT_Package:
+                    case CONSTANT_Module:
+                    case CONSTANT_String:
+                        int index = in.readUnsignedShort();
+                        pool[i] = new IndexEntry(tag, index);
+                        break;
+
+                    case CONSTANT_Double:
+                        double dvalue = in.readDouble();
+                        pool[i] = new ValueEntry(tag, dvalue);
+                        i++;
+                        break;
+
+                    case CONSTANT_Fieldref:
+                    case CONSTANT_InterfaceMethodref:
+                    case CONSTANT_Methodref:
+                    case CONSTANT_InvokeDynamic:
+                    case CONSTANT_NameAndType:
+                        int index1 = in.readUnsignedShort();
+                        int index2 = in.readUnsignedShort();
+                        pool[i] = new Index2Entry(tag, index1, index2);
+                        break;
+
+                    case CONSTANT_MethodHandle:
+                        int refKind = in.readUnsignedByte();
+                        index = in.readUnsignedShort();
+                        pool[i] = new Index2Entry(tag, refKind, index);
+                        break;
+
+                    case CONSTANT_MethodType:
+                        index = in.readUnsignedShort();
+                        pool[i] = new IndexEntry(tag, index);
+                        break;
+
+                    case CONSTANT_Float:
+                        float fvalue = in.readFloat();
+                        pool[i] = new ValueEntry(tag, fvalue);
+                        break;
+
+                    case CONSTANT_Integer:
+                        int ivalue = in.readInt();
+                        pool[i] = new ValueEntry(tag, ivalue);
+                        break;
+
+                    case CONSTANT_Long:
+                        long lvalue = in.readLong();
+                        pool[i] = new ValueEntry(tag, lvalue);
+                        i++;
+                        break;
+
+                    default:
+                        throw invalidModuleDescriptor("Bad constant pool entry: "
+                                                      + i);
+                }
+            }
+        }
+
+        String getClassName(int index) {
+            checkIndex(index);
+            Entry e = pool[index];
+            if (e.tag != CONSTANT_Class) {
+                throw invalidModuleDescriptor("CONSTANT_Class expected at entry: "
+                                              + index);
+            }
+            String value = getUtf8(((IndexEntry) e).index);
+            checkUnqualifiedName("CONSTANT_Class", index, value);
+            return value.replace('/', '.');  // internal form -> binary name
+        }
+
+        String getPackageName(int index) {
+            checkIndex(index);
+            Entry e = pool[index];
+            if (e.tag != CONSTANT_Package) {
+                throw invalidModuleDescriptor("CONSTANT_Package expected at entry: "
+                                              + index);
+            }
+            String value = getUtf8(((IndexEntry) e).index);
+            checkUnqualifiedName("CONSTANT_Package", index, value);
+            return value.replace('/', '.');  // internal form -> binary name
+        }
+
+        String getModuleName(int index) {
+            checkIndex(index);
+            Entry e = pool[index];
+            if (e.tag != CONSTANT_Module) {
+                throw invalidModuleDescriptor("CONSTANT_Module expected at entry: "
+                                              + index);
+            }
+            String value = getUtf8(((IndexEntry) e).index);
+            return decodeModuleName(index, value);
+        }
+
+        String getUtf8(int index) {
+            checkIndex(index);
+            Entry e = pool[index];
+            if (e.tag != CONSTANT_Utf8) {
+                throw invalidModuleDescriptor("CONSTANT_Utf8 expected at entry: "
+                                              + index);
+            }
+            return (String) (((ValueEntry) e).value);
+        }
+
+        void checkIndex(int index) {
+            if (index < 1 || index >= pool.length)
+                throw invalidModuleDescriptor("Index into constant pool out of range");
+        }
+
+        void checkUnqualifiedName(String what, int index, String value) {
+            int len = value.length();
+            if (len == 0) {
+                throw invalidModuleDescriptor(what + " at entry " + index
+                                              + " has zero length");
+            }
+            for (int i=0; i<len; i++) {
+                char c = value.charAt(i);
+                if (c == '.' || c == ';' || c == '[') {
+                    throw invalidModuleDescriptor(what + " at entry " + index
+                                                  + " has illegal character: '"
+                                                  + c + "'");
+                }
+            }
+        }
+
+        /**
+         * "Decode" a module name that has been read from the constant pool.
+         */
+        String decodeModuleName(int index, String value) {
+            int len = value.length();
+            if (len == 0) {
+                throw invalidModuleDescriptor("CONSTANT_Module at entry "
+                                              + index + " is zero length");
+            }
+            int i = 0;
+            while (i < len) {
+                int cp = value.codePointAt(i);
+                if (cp == ':' || cp == '@' || cp < 0x20) {
+                    throw invalidModuleDescriptor("CONSTANT_Module at entry "
+                                                  + index + " has illegal character: "
+                                                  + Character.getName(cp));
+                }
+
+                // blackslash is the escape character
+                if (cp == '\\')
+                    return decodeModuleName(index, i, value);
+
+                i += Character.charCount(cp);
+            }
+            return value;
+        }
+
+        /**
+         * "Decode" a module name that has been read from the constant pool and
+         * partly checked for illegal characters (up to position {@code i}).
+         */
+        String decodeModuleName(int index, int i, String value) {
+            StringBuilder sb = new StringBuilder();
+
+            // copy the code points that have been checked
+            int j = 0;
+            while (j < i) {
+                int cp = value.codePointAt(j);
+                sb.appendCodePoint(cp);
+                j += Character.charCount(cp);
+            }
+
+            // decode from position {@code i} to end
+            int len = value.length();
+            while (i < len) {
+                int cp = value.codePointAt(i);
+                if (cp == ':' || cp == '@' || cp < 0x20) {
+                    throw invalidModuleDescriptor("CONSTANT_Module at entry "
+                                                  + index + " has illegal character: "
+                                                  + Character.getName(cp));
+                }
+
+                // blackslash is the escape character
+                if (cp == '\\') {
+                    j = i + Character.charCount(cp);
+                    if (j >= len) {
+                        throw invalidModuleDescriptor("CONSTANT_Module at entry "
+                                                       + index + " has illegal "
+                                                       + "escape sequence");
+                    }
+                    int next = value.codePointAt(j);
+                    if (next != '\\' && next != ':' && next != '@') {
+                        throw invalidModuleDescriptor("CONSTANT_Module at entry "
+                                                      + index + " has illegal "
+                                                      + "escape sequence");
+                    }
+                    sb.appendCodePoint(next);
+                    i += Character.charCount(next);
+                } else {
+                    sb.appendCodePoint(cp);
+                }
+
+                i += Character.charCount(cp);
+            }
+            return sb.toString();
+        }
+    }
+
+    /**
+     * A DataInput implementation that reads from a ByteBuffer.
+     */
+    private static class DataInputWrapper implements DataInput {
+        private final ByteBuffer bb;
+
+        DataInputWrapper(ByteBuffer bb) {
+            this.bb = bb;
+        }
+
+        @Override
+        public void readFully(byte b[]) throws IOException {
+            readFully(b, 0, b.length);
+        }
+
+        @Override
+        public void readFully(byte b[], int off, int len) throws IOException {
+            try {
+                bb.get(b, off, len);
+            } catch (BufferUnderflowException e) {
+                throw new EOFException(e.getMessage());
+            }
+        }
+
+        @Override
+        public int skipBytes(int n) {
+            int skip = Math.min(n, bb.remaining());
+            bb.position(bb.position() + skip);
+            return skip;
+        }
+
+        @Override
+        public boolean readBoolean() throws IOException {
+            try {
+                int ch = bb.get();
+                return (ch != 0);
+            } catch (BufferUnderflowException e) {
+                throw new EOFException(e.getMessage());
+            }
+        }
+
+        @Override
+        public byte readByte() throws IOException {
+            try {
+                return bb.get();
+            } catch (BufferUnderflowException e) {
+                throw new EOFException(e.getMessage());
+            }
+        }
+
+        @Override
+        public int readUnsignedByte() throws IOException {
+            try {
+                return ((int) bb.get()) & 0xff;
+            } catch (BufferUnderflowException e) {
+                throw new EOFException(e.getMessage());
+            }
+        }
+
+        @Override
+        public short readShort() throws IOException {
+            try {
+                return bb.getShort();
+            } catch (BufferUnderflowException e) {
+                throw new EOFException(e.getMessage());
+            }
+        }
+
+        @Override
+        public int readUnsignedShort() throws IOException {
+            try {
+                return ((int) bb.getShort()) & 0xffff;
+            } catch (BufferUnderflowException e) {
+                throw new EOFException(e.getMessage());
+            }
+        }
+
+        @Override
+        public char readChar() throws IOException {
+            try {
+                return bb.getChar();
+            } catch (BufferUnderflowException e) {
+                throw new EOFException(e.getMessage());
+            }
+        }
+
+        @Override
+        public int readInt() throws IOException {
+            try {
+                return bb.getInt();
+            } catch (BufferUnderflowException e) {
+                throw new EOFException(e.getMessage());
+            }
+        }
+
+        @Override
+        public long readLong() throws IOException {
+            try {
+                return bb.getLong();
+            } catch (BufferUnderflowException e) {
+                throw new EOFException(e.getMessage());
+            }
+        }
+
+        @Override
+        public float readFloat() throws IOException {
+            try {
+                return bb.getFloat();
+            } catch (BufferUnderflowException e) {
+                throw new EOFException(e.getMessage());
+            }
+        }
+
+        @Override
+        public double readDouble() throws IOException {
+            try {
+                return bb.getDouble();
+            } catch (BufferUnderflowException e) {
+                throw new EOFException(e.getMessage());
+            }
+        }
+
+        @Override
+        public String readLine() {
+            throw new RuntimeException("not implemented");
+        }
+
+        @Override
+        public String readUTF() throws IOException {
+            // ### Need to measure the performance and feasibility of using
+            // the UTF-8 decoder instead.
+            return DataInputStream.readUTF(this);
+        }
+    }
+
+    /**
+     * Returns an InvalidModuleDescriptorException with the given detail
+     * message
+     */
+    private static InvalidModuleDescriptorException
+    invalidModuleDescriptor(String msg) {
+        return new InvalidModuleDescriptorException(msg);
+    }
+
+    /**
+     * Returns an InvalidModuleDescriptorException with a detail message to
+     * indicate that the class file is truncated.
+     */
+    private static InvalidModuleDescriptorException truncatedModuleDescriptor() {
+        return invalidModuleDescriptor("Truncated module-info.class");
+    }
+
+}