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src/java.xml/share/classes/com/sun/org/apache/bcel/internal/classfile/Constant.java
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@@ -1,8 +1,7 @@
/*
- * reserved comment block
- * DO NOT REMOVE OR ALTER!
+ * Copyright (c) 2017, Oracle and/or its affiliates. All rights reserved.
*/
/*
* Licensed to the Apache Software Foundation (ASF) under one or more
* contributor license agreements. See the NOTICE file distributed with
* this work for additional information regarding copyright ownership.
@@ -16,100 +15,183 @@
* distributed under the License is distributed on an "AS IS" BASIS,
* WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
* See the License for the specific language governing permissions and
* limitations under the License.
*/
-
package com.sun.org.apache.bcel.internal.classfile;
+import java.io.DataInput;
+import java.io.DataOutputStream;
+import java.io.IOException;
-import com.sun.org.apache.bcel.internal.Constants;
-import java.io.*;
+import com.sun.org.apache.bcel.internal.Const;
+import com.sun.org.apache.bcel.internal.util.BCELComparator;
/**
- * Abstract superclass for classes to represent the different constant types
- * in the constant pool of a class file. The classes keep closely to
- * the JVM specification.
+ * Abstract superclass for classes to represent the different constant types in
+ * the constant pool of a class file. The classes keep closely to the JVM
+ * specification.
*
- * @author <A HREF="mailto:markus.dahm@berlin.de">M. Dahm</A>
+ * @version $Id: Constant.java 1749603 2016-06-21 20:50:19Z ggregory $
*/
-public abstract class Constant implements Cloneable, Node, Serializable {
+public abstract class Constant implements Cloneable, Node {
+
+ private static BCELComparator bcelComparator = new BCELComparator() {
+
+ @Override
+ public boolean equals(final Object o1, final Object o2) {
+ final Constant THIS = (Constant) o1;
+ final Constant THAT = (Constant) o2;
+ return THIS.toString().equals(THAT.toString());
+ }
+
+ @Override
+ public int hashCode(final Object o) {
+ final Constant THIS = (Constant) o;
+ return THIS.toString().hashCode();
+ }
+ };
+
/* In fact this tag is redundant since we can distinguish different
* `Constant' objects by their type, i.e., via `instanceof'. In some
* places we will use the tag for switch()es anyway.
*
* First, we want match the specification as closely as possible. Second we
* need the tag as an index to select the corresponding class name from the
* `CONSTANT_NAMES' array.
*/
- protected byte tag;
+ private byte tag;
- Constant(byte tag) { this.tag = tag; }
+ Constant(final byte tag) {
+ this.tag = tag;
+ }
/**
* Called by objects that are traversing the nodes of the tree implicitely
* defined by the contents of a Java class. I.e., the hierarchy of methods,
* fields, attributes, etc. spawns a tree of objects.
*
* @param v Visitor object
*/
+ @Override
public abstract void accept(Visitor v);
public abstract void dump(DataOutputStream file) throws IOException;
/**
* @return Tag of constant, i.e., its type. No setTag() method to avoid
* confusion.
*/
- public final byte getTag() { return tag; }
+ public final byte getTag() {
+ return tag;
+ }
/**
* @return String representation.
*/
+ @Override
public String toString() {
- return Constants.CONSTANT_NAMES[tag] + "[" + tag + "]";
+ return Const.getConstantName(tag) + "[" + tag + "]";
}
/**
* @return deep copy of this constant
*/
public Constant copy() {
try {
- return (Constant)super.clone();
- } catch(CloneNotSupportedException e) {}
-
+ return (Constant) super.clone();
+ } catch (final CloneNotSupportedException e) {
+ // TODO should this throw?
+ }
return null;
}
- public Object clone() throws CloneNotSupportedException {
+ @Override
+ public Object clone() {
+ try {
return super.clone();
+ } catch (final CloneNotSupportedException e) {
+ throw new Error("Clone Not Supported"); // never happens
+ }
}
/**
- * Read one constant from the given file, the type depends on a tag byte.
+ * Read one constant from the given input, the type depends on a tag byte.
*
- * @param file Input stream
+ * @param input Input stream
* @return Constant object
+ * @since 6.0 made public
*/
- static final Constant readConstant(DataInputStream file)
- throws IOException, ClassFormatException
- {
- byte b = file.readByte(); // Read tag byte
-
- switch(b) {
- case Constants.CONSTANT_Class: return new ConstantClass(file);
- case Constants.CONSTANT_Fieldref: return new ConstantFieldref(file);
- case Constants.CONSTANT_Methodref: return new ConstantMethodref(file);
- case Constants.CONSTANT_InterfaceMethodref: return new
- ConstantInterfaceMethodref(file);
- case Constants.CONSTANT_String: return new ConstantString(file);
- case Constants.CONSTANT_Integer: return new ConstantInteger(file);
- case Constants.CONSTANT_Float: return new ConstantFloat(file);
- case Constants.CONSTANT_Long: return new ConstantLong(file);
- case Constants.CONSTANT_Double: return new ConstantDouble(file);
- case Constants.CONSTANT_NameAndType: return new ConstantNameAndType(file);
- case Constants.CONSTANT_Utf8: return new ConstantUtf8(file);
+ public static Constant readConstant(final DataInput input) throws IOException,
+ ClassFormatException {
+ final byte b = input.readByte(); // Read tag byte
+ switch (b) {
+ case Const.CONSTANT_Class:
+ return new ConstantClass(input);
+ case Const.CONSTANT_Fieldref:
+ return new ConstantFieldref(input);
+ case Const.CONSTANT_Methodref:
+ return new ConstantMethodref(input);
+ case Const.CONSTANT_InterfaceMethodref:
+ return new ConstantInterfaceMethodref(input);
+ case Const.CONSTANT_String:
+ return new ConstantString(input);
+ case Const.CONSTANT_Integer:
+ return new ConstantInteger(input);
+ case Const.CONSTANT_Float:
+ return new ConstantFloat(input);
+ case Const.CONSTANT_Long:
+ return new ConstantLong(input);
+ case Const.CONSTANT_Double:
+ return new ConstantDouble(input);
+ case Const.CONSTANT_NameAndType:
+ return new ConstantNameAndType(input);
+ case Const.CONSTANT_Utf8:
+ return ConstantUtf8.getInstance(input);
+ case Const.CONSTANT_MethodHandle:
+ return new ConstantMethodHandle(input);
+ case Const.CONSTANT_MethodType:
+ return new ConstantMethodType(input);
+ case Const.CONSTANT_InvokeDynamic:
+ return new ConstantInvokeDynamic(input);
default:
throw new ClassFormatException("Invalid byte tag in constant pool: " + b);
}
}
+
+ /**
+ * @return Comparison strategy object
+ */
+ public static BCELComparator getComparator() {
+ return bcelComparator;
+ }
+
+ /**
+ * @param comparator Comparison strategy object
+ */
+ public static void setComparator(final BCELComparator comparator) {
+ bcelComparator = comparator;
+ }
+
+ /**
+ * Return value as defined by given BCELComparator strategy. By default two
+ * Constant objects are said to be equal when the result of toString() is
+ * equal.
+ *
+ * @see java.lang.Object#equals(java.lang.Object)
+ */
+ @Override
+ public boolean equals(final Object obj) {
+ return bcelComparator.equals(this, obj);
+ }
+
+ /**
+ * Return value as defined by given BCELComparator strategy. By default
+ * return the hashcode of the result of toString().
+ *
+ * @see java.lang.Object#hashCode()
+ */
+ @Override
+ public int hashCode() {
+ return bcelComparator.hashCode(this);
+ }
}
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