/*
* Copyright (c) 2007, 2009, 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 com.sun.tools.classfile;
import java.io.IOException;
import java.util.Iterator;
import java.util.NoSuchElementException;
/**
* See JVMS, section 4.8.3.
*
* <p><b>This is NOT part of any supported API.
* If you write code that depends on this, you do so at your own risk.
* This code and its internal interfaces are subject to change or
* deletion without notice.</b>
*/
public class Code_attribute extends Attribute {
public class InvalidIndex extends AttributeException {
private static final long serialVersionUID = -8904527774589382802L;
InvalidIndex(int index) {
this.index = index;
}
@Override
public String getMessage() {
// i18n
return "invalid index " + index + " in Code attribute";
}
public final int index;
}
Code_attribute(ClassReader cr, int name_index, int length)
throws IOException, ConstantPoolException {
super(name_index, length);
max_stack = cr.readUnsignedShort();
max_locals = cr.readUnsignedShort();
code_length = cr.readInt();
code = new byte[code_length];
cr.readFully(code);
exception_table_langth = cr.readUnsignedShort();
exception_table = new Exception_data[exception_table_langth];
for (int i = 0; i < exception_table_langth; i++)
exception_table[i] = new Exception_data(cr);
attributes = new Attributes(cr);
}
public int getByte(int offset) throws InvalidIndex {
if (offset < 0 || offset >= code.length)
throw new InvalidIndex(offset);
return code[offset];
}
public int getUnsignedByte(int offset) throws InvalidIndex {
if (offset < 0 || offset >= code.length)
throw new InvalidIndex(offset);
return code[offset] & 0xff;
}
public int getShort(int offset) throws InvalidIndex {
if (offset < 0 || offset + 1 >= code.length)
throw new InvalidIndex(offset);
return (code[offset] << 8) | (code[offset + 1] & 0xFF);
}
public int getUnsignedShort(int offset) throws InvalidIndex {
if (offset < 0 || offset + 1 >= code.length)
throw new InvalidIndex(offset);
return ((code[offset] << 8) | (code[offset + 1] & 0xFF)) & 0xFFFF;
}
public int getInt(int offset) throws InvalidIndex {
if (offset < 0 || offset + 3 >= code.length)
throw new InvalidIndex(offset);
return (getShort(offset) << 16) | (getShort(offset + 2) & 0xFFFF);
}
public <R, D> R accept(Visitor<R, D> visitor, D data) {
return visitor.visitCode(this, data);
}
public Iterable<Instruction> getInstructions() {
return new Iterable<Instruction>() {
public Iterator<Instruction> iterator() {
return new Iterator<Instruction>() {
public boolean hasNext() {
return (next != null);
}
public Instruction next() {
if (next == null)
throw new NoSuchElementException();
current = next;
pc += current.length();
next = (pc < code.length ? new Instruction(code, pc) : null);
return current;
}
public void remove() {
throw new UnsupportedOperationException("Not supported.");
}
Instruction current = null;
int pc = 0;
Instruction next = new Instruction(code, pc);
};
}
};
}
public final int max_stack;
public final int max_locals;
public final int code_length;
public final byte[] code;
public final int exception_table_langth;
public final Exception_data[] exception_table;
public final Attributes attributes;
public class Exception_data {
Exception_data(ClassReader cr) throws IOException {
start_pc = cr.readUnsignedShort();
end_pc = cr.readUnsignedShort();
handler_pc = cr.readUnsignedShort();
catch_type = cr.readUnsignedShort();
}
public final int start_pc;
public final int end_pc;
public final int handler_pc;
public final int catch_type;
}
}