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src/java.xml/share/classes/com/sun/org/apache/bcel/internal/generic/LocalVariableInstruction.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.
@@ -16,37 +15,41 @@
* 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.generic;
-import java.io.*;
+import java.io.DataOutputStream;
+import java.io.IOException;
+
+import com.sun.org.apache.bcel.internal.Const;
import com.sun.org.apache.bcel.internal.util.ByteSequence;
-import com.sun.org.apache.bcel.internal.classfile.Utility;
-import com.sun.org.apache.bcel.internal.Constants;
/**
* Abstract super class for instructions dealing with local variables.
*
- * @author <A HREF="mailto:markus.dahm@berlin.de">M. Dahm</A>
+ * @version $Id: LocalVariableInstruction.java 1747278 2016-06-07 17:28:43Z
+ * britter $
*/
-public abstract class LocalVariableInstruction extends Instruction
- implements TypedInstruction, IndexedInstruction {
- protected int n = -1; // index of referenced variable
+public abstract class LocalVariableInstruction extends Instruction implements TypedInstruction,
+ IndexedInstruction {
+
+ private int n = -1; // index of referenced variable
private short c_tag = -1; // compact version, such as ILOAD_0
private short canon_tag = -1; // canonical tag such as ILOAD
- private final boolean wide() { return n > Constants.MAX_BYTE; }
+ private boolean wide() {
+ return n > Const.MAX_BYTE;
+ }
/**
* Empty constructor needed for the Class.newInstance() statement in
- * Instruction.readInstruction(). Not to be used otherwise.
- * tag and length are defined in readInstruction and initFromFile, respectively.
+ * Instruction.readInstruction(). Not to be used otherwise. tag and length
+ * are defined in readInstruction and initFromFile, respectively.
*/
- LocalVariableInstruction(short canon_tag, short c_tag) {
+ LocalVariableInstruction(final short canon_tag, final short c_tag) {
super();
this.canon_tag = canon_tag;
this.c_tag = c_tag;
}
@@ -60,134 +63,159 @@
/**
* @param opcode Instruction opcode
* @param c_tag Instruction number for compact version, ALOAD_0, e.g.
* @param n local variable index (unsigned short)
*/
- protected LocalVariableInstruction(short opcode, short c_tag, int n) {
- super(opcode, (short)2);
-
+ protected LocalVariableInstruction(final short opcode, final short c_tag, final int n) {
+ super(opcode, (short) 2);
this.c_tag = c_tag;
canon_tag = opcode;
-
setIndex(n);
}
/**
* Dump instruction as byte code to stream out.
+ *
* @param out Output stream
*/
- public void dump(DataOutputStream out) throws IOException {
- if(wide()) // Need WIDE prefix ?
- out.writeByte(Constants.WIDE);
-
- out.writeByte(opcode);
-
- if(length > 1) { // Otherwise ILOAD_n, instruction, e.g.
- if(wide())
+ @Override
+ public void dump(final DataOutputStream out) throws IOException {
+ if (wide()) {
+ out.writeByte(Const.WIDE);
+ }
+ out.writeByte(super.getOpcode());
+ if (super.getLength() > 1) { // Otherwise ILOAD_n, instruction, e.g.
+ if (wide()) {
out.writeShort(n);
- else
+ } else {
out.writeByte(n);
}
}
+ }
/**
* Long output format:
*
- * <name of opcode> "["<opcode number>"]"
- * "("<length of instruction>")" "<"< local variable index>">"
+ * <name of opcode> "["<opcode number>"]" "("<length of
+ * instruction>")" "<"< local variable index>">"
*
* @param verbose long/short format switch
* @return mnemonic for instruction
*/
- public String toString(boolean verbose) {
- if(((opcode >= Constants.ILOAD_0) &&
- (opcode <= Constants.ALOAD_3)) ||
- ((opcode >= Constants.ISTORE_0) &&
- (opcode <= Constants.ASTORE_3)))
+ @Override
+ public String toString(final boolean verbose) {
+ final short _opcode = super.getOpcode();
+ if (((_opcode >= Const.ILOAD_0) && (_opcode <= Const.ALOAD_3))
+ || ((_opcode >= Const.ISTORE_0) && (_opcode <= Const.ASTORE_3))) {
return super.toString(verbose);
- else
+ }
return super.toString(verbose) + " " + n;
}
/**
* Read needed data (e.g. index) from file.
- * PRE: (ILOAD <= tag <= ALOAD_3) || (ISTORE <= tag <= ASTORE_3)
- */
- protected void initFromFile(ByteSequence bytes, boolean wide)
- throws IOException
- {
- if(wide) {
+ * <pre>
+ * (ILOAD <= tag <= ALOAD_3) || (ISTORE <= tag <= ASTORE_3)
+ * </pre>
+ */
+ @Override
+ protected void initFromFile(final ByteSequence bytes, final boolean wide) throws IOException {
+ if (wide) {
n = bytes.readUnsignedShort();
- length = 4;
- } else if(((opcode >= Constants.ILOAD) &&
- (opcode <= Constants.ALOAD)) ||
- ((opcode >= Constants.ISTORE) &&
- (opcode <= Constants.ASTORE))) {
+ super.setLength(4);
+ } else {
+ final short _opcode = super.getOpcode();
+ if (((_opcode >= Const.ILOAD) && (_opcode <= Const.ALOAD))
+ || ((_opcode >= Const.ISTORE) && (_opcode <= Const.ASTORE))) {
n = bytes.readUnsignedByte();
- length = 2;
- } else if(opcode <= Constants.ALOAD_3) { // compact load instruction such as ILOAD_2
- n = (opcode - Constants.ILOAD_0) % 4;
- length = 1;
+ super.setLength(2);
+ } else if (_opcode <= Const.ALOAD_3) { // compact load instruction such as ILOAD_2
+ n = (_opcode - Const.ILOAD_0) % 4;
+ super.setLength(1);
} else { // Assert ISTORE_0 <= tag <= ASTORE_3
- n = (opcode - Constants.ISTORE_0) % 4;
- length = 1;
+ n = (_opcode - Const.ISTORE_0) % 4;
+ super.setLength(1);
+ }
}
}
/**
- * @return local variable index referred by this instruction.
+ * @return local variable index (n) referred by this instruction.
*/
- public final int getIndex() { return n; }
+ @Override
+ public final int getIndex() {
+ return n;
+ }
/**
- * Set the local variable index
+ * Set the local variable index. also updates opcode and length TODO Why?
+ *
+ * @see #setIndexOnly(int)
*/
- public void setIndex(int n) {
- if((n < 0) || (n > Constants.MAX_SHORT))
+ @Override
+ public void setIndex(final int n) { // TODO could be package-protected?
+ if ((n < 0) || (n > Const.MAX_SHORT)) {
throw new ClassGenException("Illegal value: " + n);
-
+ }
this.n = n;
-
- if(n >= 0 && n <= 3) { // Use more compact instruction xLOAD_n
- opcode = (short)(c_tag + n);
- length = 1;
+ // Cannot be < 0 as this is checked above
+ if (n <= 3) { // Use more compact instruction xLOAD_n
+ super.setOpcode((short) (c_tag + n));
+ super.setLength(1);
} else {
- opcode = canon_tag;
-
- if(wide()) // Need WIDE prefix ?
- length = 4;
- else
- length = 2;
+ super.setOpcode(canon_tag);
+ if (wide()) {
+ super.setLength(4);
+ } else {
+ super.setLength(2);
+ }
}
}
- /** @return canonical tag for instruction, e.g., ALOAD for ALOAD_0
+ /**
+ * @return canonical tag for instruction, e.g., ALOAD for ALOAD_0
*/
public short getCanonicalTag() {
return canon_tag;
}
/**
- * Returns the type associated with the instruction -
- * in case of ALOAD or ASTORE Type.OBJECT is returned.
- * This is just a bit incorrect, because ALOAD and ASTORE
- * may work on every ReferenceType (including Type.NULL) and
- * ASTORE may even work on a ReturnaddressType .
+ * Returns the type associated with the instruction - in case of ALOAD or
+ * ASTORE Type.OBJECT is returned. This is just a bit incorrect, because
+ * ALOAD and ASTORE may work on every ReferenceType (including Type.NULL)
+ * and ASTORE may even work on a ReturnaddressType .
+ *
* @return type associated with the instruction
*/
- public Type getType(ConstantPoolGen cp) {
- switch(canon_tag) {
- case Constants.ILOAD: case Constants.ISTORE:
+ @Override
+ public Type getType(final ConstantPoolGen cp) {
+ switch (canon_tag) {
+ case Const.ILOAD:
+ case Const.ISTORE:
return Type.INT;
- case Constants.LLOAD: case Constants.LSTORE:
+ case Const.LLOAD:
+ case Const.LSTORE:
return Type.LONG;
- case Constants.DLOAD: case Constants.DSTORE:
+ case Const.DLOAD:
+ case Const.DSTORE:
return Type.DOUBLE;
- case Constants.FLOAD: case Constants.FSTORE:
+ case Const.FLOAD:
+ case Const.FSTORE:
return Type.FLOAT;
- case Constants.ALOAD: case Constants.ASTORE:
+ case Const.ALOAD:
+ case Const.ASTORE:
return Type.OBJECT;
-
- default: throw new ClassGenException("Oops: unknown case in switch" + canon_tag);
+ default:
+ throw new ClassGenException("Oops: unknown case in switch" + canon_tag);
}
}
+
+ /**
+ * Sets the index of the referenced variable (n) only
+ *
+ * @since 6.0
+ * @see #setIndex(int)
+ */
+ final void setIndexOnly(final int n) {
+ this.n = n;
+ }
}
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