| /* |
| * Copyright (c) 2017, 2020, 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. |
| * The ASF licenses this file to You 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 |
| * |
| * http://www.apache.org/licenses/LICENSE-2.0 |
| * |
| * 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. |
| */ |
| |
| package com.sun.org.apache.bcel.internal.generic; |
| |
| import java.io.DataOutputStream; |
| import java.io.IOException; |
| |
| import com.sun.org.apache.bcel.internal.ExceptionConst; |
| import com.sun.org.apache.bcel.internal.util.ByteSequence; |
| |
| /** |
| * LDC - Push item from constant pool. |
| * |
| * <PRE>Stack: ... -> ..., item</PRE> |
| * |
| * @LastModified: Jan 2020 |
| */ |
| public class LDC extends CPInstruction implements PushInstruction, ExceptionThrower { |
| |
| /** |
| * Empty constructor needed for Instruction.readInstruction. |
| * Not to be used otherwise. |
| */ |
| LDC() { |
| } |
| |
| |
| public LDC(final int index) { |
| super(com.sun.org.apache.bcel.internal.Const.LDC_W, index); |
| setSize(); |
| } |
| |
| |
| // Adjust to proper size |
| protected final void setSize() { |
| if (super.getIndex() <= com.sun.org.apache.bcel.internal.Const.MAX_BYTE) { // Fits in one byte? |
| super.setOpcode(com.sun.org.apache.bcel.internal.Const.LDC); |
| super.setLength(2); |
| } else { |
| super.setOpcode(com.sun.org.apache.bcel.internal.Const.LDC_W); |
| super.setLength(3); |
| } |
| } |
| |
| |
| /** |
| * Dump instruction as byte code to stream out. |
| * @param out Output stream |
| */ |
| @Override |
| public void dump( final DataOutputStream out ) throws IOException { |
| out.writeByte(super.getOpcode()); |
| if (super.getLength() == 2) { // TODO useless check? |
| out.writeByte(super.getIndex()); |
| } else { |
| out.writeShort(super.getIndex()); |
| } |
| } |
| |
| |
| /** |
| * Set the index to constant pool and adjust size. |
| */ |
| @Override |
| public final void setIndex( final int index ) { |
| super.setIndex(index); |
| setSize(); |
| } |
| |
| |
| /** |
| * Read needed data (e.g. index) from file. |
| */ |
| @Override |
| protected void initFromFile( final ByteSequence bytes, final boolean wide ) throws IOException { |
| super.setLength(2); |
| super.setIndex(bytes.readUnsignedByte()); |
| } |
| |
| |
| public Object getValue( final ConstantPoolGen cpg ) { |
| com.sun.org.apache.bcel.internal.classfile.Constant c = cpg.getConstantPool().getConstant(super.getIndex()); |
| switch (c.getTag()) { |
| case com.sun.org.apache.bcel.internal.Const.CONSTANT_String: |
| final int i = ((com.sun.org.apache.bcel.internal.classfile.ConstantString) c).getStringIndex(); |
| c = cpg.getConstantPool().getConstant(i); |
| return ((com.sun.org.apache.bcel.internal.classfile.ConstantUtf8) c).getBytes(); |
| case com.sun.org.apache.bcel.internal.Const.CONSTANT_Float: |
| return ((com.sun.org.apache.bcel.internal.classfile.ConstantFloat) c).getBytes(); |
| case com.sun.org.apache.bcel.internal.Const.CONSTANT_Integer: |
| return ((com.sun.org.apache.bcel.internal.classfile.ConstantInteger) c).getBytes(); |
| case com.sun.org.apache.bcel.internal.Const.CONSTANT_Class: |
| final int nameIndex = ((com.sun.org.apache.bcel.internal.classfile.ConstantClass) c).getNameIndex(); |
| c = cpg.getConstantPool().getConstant(nameIndex); |
| return new ObjectType(((com.sun.org.apache.bcel.internal.classfile.ConstantUtf8) c).getBytes()); |
| default: // Never reached |
| throw new RuntimeException("Unknown or invalid constant type at " + super.getIndex()); |
| } |
| } |
| |
| |
| @Override |
| public Type getType( final ConstantPoolGen cpg ) { |
| switch (cpg.getConstantPool().getConstant(super.getIndex()).getTag()) { |
| case com.sun.org.apache.bcel.internal.Const.CONSTANT_String: |
| return Type.STRING; |
| case com.sun.org.apache.bcel.internal.Const.CONSTANT_Float: |
| return Type.FLOAT; |
| case com.sun.org.apache.bcel.internal.Const.CONSTANT_Integer: |
| return Type.INT; |
| case com.sun.org.apache.bcel.internal.Const.CONSTANT_Class: |
| return Type.CLASS; |
| default: // Never reached |
| throw new RuntimeException("Unknown or invalid constant type at " + super.getIndex()); |
| } |
| } |
| |
| |
| @Override |
| public Class<?>[] getExceptions() { |
| return ExceptionConst.createExceptions(ExceptionConst.EXCS.EXCS_STRING_RESOLUTION); |
| } |
| |
| |
| /** |
| * Call corresponding visitor method(s). The order is: |
| * Call visitor methods of implemented interfaces first, then |
| * call methods according to the class hierarchy in descending order, |
| * i.e., the most specific visitXXX() call comes last. |
| * |
| * @param v Visitor object |
| */ |
| @Override |
| public void accept( final Visitor v ) { |
| v.visitStackProducer(this); |
| v.visitPushInstruction(this); |
| v.visitExceptionThrower(this); |
| v.visitTypedInstruction(this); |
| v.visitCPInstruction(this); |
| v.visitLDC(this); |
| } |
| } |