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fernflower/src/org/jetbrains/java/decompiler/struct/StructMethod.java

562 lines
17 KiB

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/*
* Copyright 2000-2014 JetBrains s.r.o.
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*
* Licensed under the Apache License, Version 2.0 (the "License");
* you may not use this file except in compliance with the License.
* You may obtain a copy of the License at
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*
* http://www.apache.org/licenses/LICENSE-2.0
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*
* Unless required by applicable law or agreed to in writing, software
* 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.
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*/
package org.jetbrains.java.decompiler.struct;
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import org.jetbrains.java.decompiler.code.*;
import org.jetbrains.java.decompiler.struct.attr.StructGeneralAttribute;
import org.jetbrains.java.decompiler.struct.attr.StructLocalVariableTableAttribute;
import org.jetbrains.java.decompiler.struct.consts.ConstantPool;
import org.jetbrains.java.decompiler.util.DataInputFullStream;
import org.jetbrains.java.decompiler.util.VBStyleCollection;
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import java.io.ByteArrayInputStream;
import java.io.ByteArrayOutputStream;
import java.io.DataOutputStream;
import java.io.IOException;
import java.util.ArrayList;
import java.util.List;
/*
method_info {
u2 access_flags;
u2 name_index;
u2 descriptor_index;
u2 attributes_count;
attribute_info attributes[attributes_count];
}
*/
public class StructMethod implements CodeConstants {
// *****************************************************************************
// public fields
// *****************************************************************************
public int name_index;
public int descriptor_index;
// *****************************************************************************
// private fields
// *****************************************************************************
private static final int[] opr_iconst = new int[]{-1, 0, 1, 2, 3, 4, 5};
private static final int[] opr_loadstore = new int[]{0, 1, 2, 3, 0, 1, 2, 3, 0, 1, 2, 3, 0, 1, 2, 3, 0, 1, 2, 3};
private static final int[] opcs_load = new int[]{opc_iload, opc_lload, opc_fload, opc_dload, opc_aload};
private static final int[] opcs_store = new int[]{opc_istore, opc_lstore, opc_fstore, opc_dstore, opc_astore};
private int accessFlags;
private VBStyleCollection<StructGeneralAttribute, String> attributes;
private int localVariables;
private int maxStack;
private String name;
private String descriptor;
private InstructionSequence seq;
private boolean containsCode = false;
private StructClass classStruct;
// lazy properties
private boolean lazy;
private boolean expanded;
private byte[] code_content;
private int code_length = 0;
private int code_fulllength = 0;
// *****************************************************************************
// constructors
// *****************************************************************************
public StructMethod(DataInputFullStream in, boolean own, StructClass clstruct) throws IOException {
this(in, true, own, clstruct);
}
public StructMethod(DataInputFullStream in, boolean lazy, boolean own, StructClass clstruct) throws IOException {
this.lazy = lazy;
this.expanded = !lazy;
this.classStruct = clstruct;
accessFlags = in.readUnsignedShort();
name_index = in.readUnsignedShort();
descriptor_index = in.readUnsignedShort();
ConstantPool pool = clstruct.getPool();
initStrings(pool, clstruct.this_class);
VBStyleCollection<StructGeneralAttribute, String> lstAttribute = new VBStyleCollection<StructGeneralAttribute, String>();
int len = in.readUnsignedShort();
for (int i = 0; i < len; i++) {
int attr_nameindex = in.readUnsignedShort();
String attrname = pool.getPrimitiveConstant(attr_nameindex).getString();
if (StructGeneralAttribute.ATTRIBUTE_CODE.equals(attrname)) {
if (!own) {
// skip code in foreign classes
in.skip(8);
in.skip(in.readInt());
in.skip(8 * in.readUnsignedShort());
}
else {
containsCode = true;
in.skip(4);
maxStack = in.readUnsignedShort();
localVariables = in.readUnsignedShort();
if (lazy) {
code_length = in.readInt();
in.skip(code_length);
int exc_length = in.readUnsignedShort();
code_fulllength = code_length + exc_length * 8 + 2;
in.skip(exc_length * 8);
}
else {
seq = parseBytecode(in, in.readInt(), pool);
}
}
// code attributes
int length = in.readUnsignedShort();
for (int j = 0; j < length; j++) {
int codeattr_nameindex = in.readUnsignedShort();
String codeattrname = pool.getPrimitiveConstant(codeattr_nameindex).getString();
readAttribute(in, pool, lstAttribute, codeattr_nameindex, codeattrname);
}
}
else {
readAttribute(in, pool, lstAttribute, attr_nameindex, attrname);
}
}
attributes = lstAttribute;
}
// *****************************************************************************
// public methods
// *****************************************************************************
public void writeToStream(DataOutputStream out) throws IOException {
out.writeShort(accessFlags);
out.writeShort(name_index);
out.writeShort(descriptor_index);
out.writeShort(attributes.size());
for (StructGeneralAttribute attr : attributes) {
if (StructGeneralAttribute.ATTRIBUTE_CODE.equals(attr.getName())) {
out.writeShort(attr.getAttribute_name_index());
if (lazy && !expanded) {
out.writeInt(10 + code_content.length);
out.writeShort(maxStack);
out.writeShort(localVariables);
out.writeInt(code_length);
out.write(code_content);
}
else {
ByteArrayOutputStream codeout = new ByteArrayOutputStream();
seq.writeCodeToStream(new DataOutputStream(codeout));
ByteArrayOutputStream excout = new ByteArrayOutputStream();
seq.writeExceptionsToStream(new DataOutputStream(excout));
out.writeInt(10 + codeout.size() + excout.size());
out.writeShort(maxStack);
out.writeShort(localVariables);
out.writeInt(codeout.size());
codeout.writeTo(out);
excout.writeTo(out);
}
// no attributes
out.writeShort(0);
}
else {
attr.writeToStream(out);
}
}
}
private void readAttribute(DataInputFullStream in, ConstantPool pool, VBStyleCollection<StructGeneralAttribute, String> lstAttribute,
int attr_nameindex, String attrname) throws IOException {
StructGeneralAttribute attribute = StructGeneralAttribute.getMatchingAttributeInstance(attr_nameindex, attrname);
if (attribute != null) {
attrname = attribute.getName();
byte[] arr = new byte[in.readInt()];
in.readFull(arr);
attribute.setInfo(arr);
attribute.initContent(pool);
if (StructGeneralAttribute.ATTRIBUTE_LOCAL_VARIABLE_TABLE.equals(attrname) &&
lstAttribute.containsKey(attrname)) {
// merge all variable tables
StructLocalVariableTableAttribute oldattr = (StructLocalVariableTableAttribute)lstAttribute.getWithKey(attrname);
oldattr.addLocalVariableTable((StructLocalVariableTableAttribute)attribute);
}
else {
lstAttribute.addWithKey(attribute, attribute.getName());
}
}
else {
in.skip(in.readInt());
}
}
private void initStrings(ConstantPool pool, int class_index) {
String[] values = pool.getClassElement(ConstantPool.METHOD, class_index, name_index, descriptor_index);
name = values[0];
descriptor = values[1];
}
public void expandData() throws IOException {
if (containsCode && lazy && !expanded) {
byte[] codearr = classStruct.getLoader().loadBytecode(this, code_fulllength);
seq = parseBytecode(new DataInputFullStream(new ByteArrayInputStream(codearr)), code_length, classStruct.getPool());
expanded = true;
}
}
public void releaseResources() throws IOException {
if (containsCode && lazy && expanded) {
seq = null;
expanded = false;
}
}
// *****************************************************************************
// private methods
// *****************************************************************************
private InstructionSequence parseBytecode(DataInputFullStream in, int length, ConstantPool pool) throws IOException {
VBStyleCollection<Instruction, Integer> collinstr = new VBStyleCollection<Instruction, Integer>();
int bytecode_version = classStruct.getBytecodeVersion();
for (int i = 0; i < length; ) {
int offset = i;
int opcode = in.readUnsignedByte();
int group = GROUP_GENERAL;
boolean wide = (opcode == opc_wide);
if (wide) {
i++;
opcode = in.readUnsignedByte();
}
List<Integer> operands = new ArrayList<Integer>();
if (opcode >= opc_iconst_m1 && opcode <= opc_iconst_5) {
operands.add(new Integer(opr_iconst[opcode - opc_iconst_m1]));
opcode = opc_bipush;
}
else if (opcode >= opc_iload_0 && opcode <= opc_aload_3) {
operands.add(new Integer(opr_loadstore[opcode - opc_iload_0]));
opcode = opcs_load[(opcode - opc_iload_0) / 4];
}
else if (opcode >= opc_istore_0 && opcode <= opc_astore_3) {
operands.add(new Integer(opr_loadstore[opcode - opc_istore_0]));
opcode = opcs_store[(opcode - opc_istore_0) / 4];
}
else {
switch (opcode) {
case opc_bipush:
operands.add(new Integer(in.readByte()));
i++;
break;
case opc_ldc:
case opc_newarray:
operands.add(new Integer(in.readUnsignedByte()));
i++;
break;
case opc_sipush:
case opc_ifeq:
case opc_ifne:
case opc_iflt:
case opc_ifge:
case opc_ifgt:
case opc_ifle:
case opc_if_icmpeq:
case opc_if_icmpne:
case opc_if_icmplt:
case opc_if_icmpge:
case opc_if_icmpgt:
case opc_if_icmple:
case opc_if_acmpeq:
case opc_if_acmpne:
case opc_goto:
case opc_jsr:
case opc_ifnull:
case opc_ifnonnull:
if (opcode != opc_sipush) {
group = GROUP_JUMP;
}
operands.add(new Integer(in.readShort()));
i += 2;
break;
case opc_ldc_w:
case opc_ldc2_w:
case opc_getstatic:
case opc_putstatic:
case opc_getfield:
case opc_putfield:
case opc_invokevirtual:
case opc_invokespecial:
case opc_invokestatic:
case opc_new:
case opc_anewarray:
case opc_checkcast:
case opc_instanceof:
operands.add(new Integer(in.readUnsignedShort()));
i += 2;
if (opcode >= opc_getstatic && opcode <= opc_putfield) {
group = GROUP_FIELDACCESS;
}
else if (opcode >= opc_invokevirtual && opcode <= opc_invokestatic) {
group = GROUP_INVOCATION;
}
break;
case opc_invokedynamic:
if (classStruct.isVersionGE_1_7()) { // instruction unused in Java 6 and before
operands.add(new Integer(in.readUnsignedShort()));
in.skip(2);
group = GROUP_INVOCATION;
i += 4;
}
break;
case opc_iload:
case opc_lload:
case opc_fload:
case opc_dload:
case opc_aload:
case opc_istore:
case opc_lstore:
case opc_fstore:
case opc_dstore:
case opc_astore:
case opc_ret:
if (wide) {
operands.add(new Integer(in.readUnsignedShort()));
i += 2;
}
else {
operands.add(new Integer(in.readUnsignedByte()));
i++;
}
if (opcode == opc_ret) {
group = GROUP_RETURN;
}
break;
case opc_iinc:
if (wide) {
operands.add(new Integer(in.readUnsignedShort()));
operands.add(new Integer(in.readShort()));
i += 4;
}
else {
operands.add(new Integer(in.readUnsignedByte()));
operands.add(new Integer(in.readByte()));
i += 2;
}
break;
case opc_goto_w:
case opc_jsr_w:
opcode = opcode == opc_jsr_w ? opc_jsr : opc_goto;
operands.add(new Integer(in.readInt()));
group = GROUP_JUMP;
i += 4;
break;
case opc_invokeinterface:
operands.add(new Integer(in.readUnsignedShort()));
operands.add(new Integer(in.readUnsignedByte()));
in.skip(1);
group = GROUP_INVOCATION;
i += 4;
break;
case opc_multianewarray:
operands.add(new Integer(in.readUnsignedShort()));
operands.add(new Integer(in.readUnsignedByte()));
i += 3;
break;
case opc_tableswitch:
in.skip((4 - (i + 1) % 4) % 4);
i += ((4 - (i + 1) % 4) % 4); // padding
operands.add(new Integer(in.readInt()));
i += 4;
int low = in.readInt();
operands.add(new Integer(low));
i += 4;
int high = in.readInt();
operands.add(new Integer(high));
i += 4;
for (int j = 0; j < high - low + 1; j++) {
operands.add(new Integer(in.readInt()));
i += 4;
}
group = GROUP_SWITCH;
break;
case opc_lookupswitch:
in.skip((4 - (i + 1) % 4) % 4);
i += ((4 - (i + 1) % 4) % 4); // padding
operands.add(new Integer(in.readInt()));
i += 4;
int npairs = in.readInt();
operands.add(new Integer(npairs));
i += 4;
for (int j = 0; j < npairs; j++) {
operands.add(new Integer(in.readInt()));
i += 4;
operands.add(new Integer(in.readInt()));
i += 4;
}
group = GROUP_SWITCH;
break;
case opc_ireturn:
case opc_lreturn:
case opc_freturn:
case opc_dreturn:
case opc_areturn:
case opc_return:
case opc_athrow:
group = GROUP_RETURN;
}
}
int[] ops = new int[operands.size()];
for (int j = 0; j < operands.size(); j++) {
ops[j] = operands.get(j).intValue();
}
Instruction instr = ConstantsUtil.getInstructionInstance(opcode, wide, group, bytecode_version, ops);
collinstr.addWithKey(instr, new Integer(offset));
i++;
}
// initialize exception table
List<ExceptionHandler> lstHandlers = new ArrayList<ExceptionHandler>();
int exception_count = in.readUnsignedShort();
for (int i = 0; i < exception_count; i++) {
ExceptionHandler handler = new ExceptionHandler();
handler.from = in.readUnsignedShort();
handler.to = in.readUnsignedShort();
handler.handler = in.readUnsignedShort();
int excclass = in.readUnsignedShort();
handler.class_index = excclass;
if (excclass != 0) {
handler.exceptionClass = pool.getPrimitiveConstant(excclass).getString();
}
lstHandlers.add(handler);
}
InstructionSequence seq = new FullInstructionSequence(collinstr, new ExceptionTable(lstHandlers));
// initialize instructions
int i = seq.length() - 1;
seq.setPointer(i);
while (i >= 0) {
Instruction instr = seq.getInstr(i--);
if (instr.group != GROUP_GENERAL) {
instr.initInstruction(seq);
}
seq.addToPointer(-1);
}
return seq;
}
// *****************************************************************************
// getter and setter methods
// *****************************************************************************
public InstructionSequence getInstructionSequence() {
return seq;
}
public String getDescriptor() {
return descriptor;
}
public String getName() {
return name;
}
public int getAccessFlags() {
return accessFlags;
}
public int getLocalVariables() {
return localVariables;
}
public VBStyleCollection<StructGeneralAttribute, String> getAttributes() {
return attributes;
}
public StructClass getClassStruct() {
return classStruct;
}
public boolean containsCode() {
return containsCode;
}
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}