/* ConstantPool Copyright (C) 1998-2002 Jochen Hoenicke.
*
* This program is free software; you can redistribute it and/or modify
* it under the terms of the GNU Lesser General Public License as published by
* the Free Software Foundation; either version 2, or (at your option)
* any later version.
*
* This program 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 for more details.
*
* You should have received a copy of the GNU Lesser General Public License
* along with this program; see the file COPYING.LESSER. If not, write to
* the Free Software Foundation, 675 Mass Ave, Cambridge, MA 02139, USA.
*
* $Id: ConstantPool.java,v 1.17.2.1 2002/05/28 17:34:00 hoenicke Exp $
*/
package jode.bytecode;
import java.io.DataInputStream;
import java.io.IOException;
/**
* This class represent the constant pool.
*
* @author Jochen Hoenicke
*/
public class ConstantPool {
public final static int CLASS = 7;
public final static int FIELDREF = 9;
public final static int METHODREF = 10;
public final static int INTERFACEMETHODREF = 11;
public final static int STRING = 8;
public final static int INTEGER = 3;
public final static int FLOAT = 4;
public final static int LONG = 5;
public final static int DOUBLE = 6;
public final static int NAMEANDTYPE = 12;
public final static int UTF8 = 1;
int count;
int[] tags;
int[] indices1, indices2;
Object[] constants;
public ConstantPool () {
}
public void read(DataInputStream stream)
throws IOException {
count = stream.readUnsignedShort();
tags = new int[count];
indices1 = new int[count];
indices2 = new int[count];
constants = new Object[count];
for (int i=1; i< count; i++) {
int tag = stream.readUnsignedByte();
tags[i] = tag;
switch (tag) {
case CLASS:
indices1[i] = stream.readUnsignedShort();
break;
case FIELDREF:
case METHODREF:
case INTERFACEMETHODREF:
indices1[i] = stream.readUnsignedShort();
indices2[i] = stream.readUnsignedShort();
break;
case STRING:
indices1[i] = stream.readUnsignedShort();
break;
case INTEGER:
constants[i] = new Integer(stream.readInt());
break;
case FLOAT:
constants[i] = new Float(stream.readFloat());
break;
case LONG:
constants[i] = new Long(stream.readLong());
tags[++i] = -LONG;
break;
case DOUBLE:
constants[i] = new Double(stream.readDouble());
tags[++i] = -DOUBLE;
break;
case NAMEANDTYPE:
indices1[i] = stream.readUnsignedShort();
indices2[i] = stream.readUnsignedShort();
break;
case UTF8:
constants[i] = stream.readUTF().intern();
break;
default:
throw new ClassFormatException("unknown constant tag");
}
}
}
public int getTag(int i) throws ClassFormatException {
if (i == 0)
throw new ClassFormatException("null tag");
return tags[i];
}
public String getUTF8(int i) throws ClassFormatException {
if (i == 0)
return null;
if (tags[i] != UTF8)
throw new ClassFormatException("Tag mismatch");
return (String)constants[i];
}
public Reference getRef(int i) throws ClassFormatException {
if (i == 0)
return null;
if (tags[i] != FIELDREF
&& tags[i] != METHODREF && tags[i] != INTERFACEMETHODREF)
throw new ClassFormatException("Tag mismatch");
if (constants[i] == null) {
int classIndex = indices1[i];
int nameTypeIndex = indices2[i];
if (tags[nameTypeIndex] != NAMEANDTYPE)
throw new ClassFormatException("Tag mismatch");
String type = getUTF8(indices2[nameTypeIndex]);
try {
if (tags[i] == FIELDREF)
TypeSignature.checkTypeSig(type);
else
TypeSignature.checkMethodTypeSig(type);
} catch (IllegalArgumentException ex) {
throw new ClassFormatException(ex.getMessage());
}
String clName = getClassType(classIndex);
constants[i] = Reference.getReference
(clName, getUTF8(indices1[nameTypeIndex]), type);
}
return (Reference) constants[i];
}
public Object getConstant(int i) throws ClassFormatException {
if (i == 0)
throw new ClassFormatException("null constant");
switch (tags[i]) {
case ConstantPool.INTEGER:
case ConstantPool.FLOAT:
case ConstantPool.LONG:
case ConstantPool.DOUBLE:
return constants[i];
case ConstantPool.STRING:
return getUTF8(indices1[i]);
}
throw new ClassFormatException("Tag mismatch: "+tags[i]);
}
public String getClassType(int i) throws ClassFormatException {
if (i == 0)
return null;
if (tags[i] != CLASS)
throw new ClassFormatException("Tag mismatch");
String clName = getUTF8(indices1[i]);
if (clName.charAt(0) != '[') {
clName = ("L"+clName+';').intern();
}
try {
TypeSignature.checkTypeSig(clName);
} catch (IllegalArgumentException ex) {
throw new ClassFormatException(ex.getMessage());
}
return clName;
}
public String getClassName(int i) throws ClassFormatException {
if (i == 0)
return null;
if (tags[i] != CLASS)
throw new ClassFormatException("Tag mismatch");
String clName = getUTF8(indices1[i]);
try {
TypeSignature.checkTypeSig("L"+clName+";");
} catch (IllegalArgumentException ex) {
throw new ClassFormatException(ex.getMessage());
}
return clName.replace('/','.').intern();
}
public String toString(int i) {
switch (tags[i]) {
case CLASS:
return "Class "+toString(indices1[i]);
case STRING:
return "String \""+toString(indices1[i])+"\"";
case INTEGER:
return "Int "+constants[i].toString();
case FLOAT:
return "Float "+constants[i].toString();
case LONG:
return "Long "+constants[i].toString();
case DOUBLE:
return "Double "+constants[i].toString();
case UTF8:
return constants[i].toString();
case FIELDREF:
return "Fieldref: "+toString(indices1[i])+"; "
+ toString(indices2[i]);
case METHODREF:
return "Methodref: "+toString(indices1[i])+"; "
+ toString(indices2[i]);
case INTERFACEMETHODREF:
return "Interfaceref: "+toString(indices1[i])+"; "
+ toString(indices2[i]);
case NAMEANDTYPE:
return "Name "+toString(indices1[i])
+"; Type "+toString(indices2[i]);
default:
return "unknown tag: "+tags[i];
}
}
public int size() {
return count;
}
public String toString() {
StringBuffer result = new StringBuffer("[ null");
for (int i=1; i< count; i++) {
result.append(", ").append(i).append(" = ").append(toString(i));
}
result.append(" ]");
return result.toString();
}
}
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