/*
* DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS HEADER.
*
* Copyright (c) 1997-2010 Oracle and/or its affiliates. All rights reserved.
*
* The contents of this file are subject to the terms of either the GNU
* General Public License Version 2 only ("GPL") or the Common Development
* and Distribution License("CDDL") (collectively, the "License"). You
* may not use this file except in compliance with the License. You can
* obtain a copy of the License at
* https://glassfish.dev.java.net/public/CDDL+GPL_1_1.html
* or packager/legal/LICENSE.txt. See the License for the specific
* language governing permissions and limitations under the License.
*
* When distributing the software, include this License Header Notice in each
* file and include the License file at packager/legal/LICENSE.txt.
*
* GPL Classpath Exception:
* Oracle designates this particular file as subject to the "Classpath"
* exception as provided by Oracle in the GPL Version 2 section of the License
* file that accompanied this code.
*
* Modifications:
* If applicable, add the following below the License Header, with the fields
* enclosed by brackets [] replaced by your own identifying information:
* "Portions Copyright [year] [name of copyright owner]"
*
* Contributor(s):
* If you wish your version of this file to be governed by only the CDDL or
* only the GPL Version 2, indicate your decision by adding "[Contributor]
* elects to include this software in this distribution under the [CDDL or GPL
* Version 2] license." If you don't indicate a single choice of license, a
* recipient has the option to distribute your version of this file under
* either the CDDL, the GPL Version 2 or to extend the choice of license to
* its licensees as provided above. However, if you add GPL Version 2 code
* and therefore, elected the GPL Version 2 license, then the option applies
* only if the new code is made subject to such option by the copyright
* holder.
*/
package com.sun.jdo.api.persistence.enhancer.classfile;
import java.util.Stack;
import java.util.Map;
//@olsen: subst: Hashtable -> Map, HashMap
/**
* A collection of static methods which manipulate type descriptors
*/
public class Descriptor implements VMConstants {
/**
* Return the number of words of arguments to the method
* based on the method signature
*/
public static int countMethodArgWords(String sig) {
if (sig.charAt(0) != '(')
throw new InsnError ("not a method signature");//NOI18N
int count = 0;
for (int idx = 1; sig.charAt(idx) != ')'; idx++) {
switch (sig.charAt(idx)) {
case 'B': /* byte */
case 'C': /* char */
case 'S': /* short */
case 'I': /* int */
case 'F': /* float */
case 'Z': /* boolean */
count++;
break;
case 'J': /* long */
case 'D': /* double */
count += 2;
break;
case 'L':
count++;
idx = sig.indexOf(';', idx);
break;
case '[':
count++;
while (sig.charAt(idx) == '[' || sig.charAt(idx) == ']')
idx++;
if (sig.charAt(idx) == 'L')
idx = sig.indexOf(';', idx);
/* else, let idx++ at loop iteration skip primitive descriptor */
break;
default:
throw new InsnError("missing case");//NOI18N
}
}
return count;
}
/**
* Return the number of words of return value for the method
* based on the method signature
*/
public static int countMethodReturnWords(String sig) {
int idx = sig.lastIndexOf(')') + 1;
if (idx == 0)
throw new InsnError ("not a method signature");//NOI18N
switch (sig.charAt(idx)) {
case 'J': /* long */
case 'D': /* double */
return 2;
case 'B': /* byte */
case 'C': /* char */
case 'S': /* short */
case 'I': /* int */
case 'F': /* float */
case 'Z': /* boolean */
case 'L': /* object */
case '[': /* array */
return 1;
case 'V': /* void */
return 0;
default:
throw new InsnError("missing case");//NOI18N
}
}
/**
* Return the stack descriptor for the result of a method
* invocation. Void return values yield "V".
*/
public static String extractResultSig(String methodSig) {
return methodSig.substring(methodSig.indexOf(')')+1);
}
/**
* Return the stack descriptor for the arguments to a method
* invocation (not including any "this" argument)
*/
public static String extractArgSig(String methodSig) {
return methodSig.substring(1, methodSig.indexOf(')'));
}
/**
* Return the reversed stack descriptor for the arguments to a method
* invocation (not including any "this" argument). The top of stack
* element will be first.
*/
public static String extractReversedArgSig(String methodSig) {
StringBuffer buf = new StringBuffer();;
reverseArgSig(buf, methodSig, 1);
return buf.toString();
}
/**
* Given a StringBuffer, a method descriptor, and a index to the
* start of an argument descriptor, append the arguments to the
* string buffer in reverse order.
*/
private static void reverseArgSig(StringBuffer buf, String methodSig,
int idx) {
char c = methodSig.charAt(idx);
if (c == ')')
return;
int startIdx = idx;
switch(c) {
case 'B':
case 'C':
case 'S':
case 'I':
case 'F':
case 'J':
case 'D':
case 'Z':
idx = idx+1;
break;
case '[':
while (methodSig.charAt(idx) == '[' || methodSig.charAt(idx) == ']')
idx++;
if (methodSig.charAt(idx) != 'L') {
idx++;
break;
}
/* fall through */
case 'L':
idx = methodSig.indexOf(';', idx) + 1;
break;
default:
throw new InsnError("bad signature char");//NOI18N
}
reverseArgSig(buf, methodSig, idx);
while (startIdx < idx)
buf.append(methodSig.charAt(startIdx++));
}
/**
* Return the number of words of a field based on its signature.
*/
//@olsen: added method
public static int countFieldWords(String sig) {
if (sig == null || sig.length() < 1)
throw new InsnError ("not a field signature");//NOI18N
switch (sig.charAt(0)) {
case 'J': /* long */
case 'D': /* double */
return 2;
case 'B': /* byte */
case 'C': /* char */
case 'S': /* short */
case 'I': /* int */
case 'F': /* float */
case 'Z': /* boolean */
case 'L': /* object */
case '[': /* array */
return 1;
default:
throw new InsnError("missing case");//NOI18N
}
}
/**
* Return the element type for the first char in the type descriptor string.
*/
//@olsen: added method
public static int elementType(String sig) {
if (sig == null || sig.length() < 1)
throw new InsnError ("not a value signature");//NOI18N
switch(sig.charAt(0)) {
case 'B':
return T_BOOLEAN;
case 'C':
return T_CHAR;
case 'Z':
return T_BYTE;
case 'S':
return T_SHORT;
case 'I':
return T_INT;
case 'J':
return T_LONG;
case 'F':
return T_FLOAT;
case 'D':
return T_DOUBLE;
case '[':
return TC_OBJECT;
case 'L':
return TC_OBJECT;
default:
throw new InsnError("bad signature char");//NOI18N
}
}
/**
* Return the element type descriptor char for the element type.
* The element type must be one of the T_ or TC_OBJECT.
*/
public static String elementSig(int valueType) {
switch(valueType) {
case T_BYTE:
return "B";//NOI18N
case T_CHAR:
return "C";//NOI18N
case T_BOOLEAN:
return "Z";//NOI18N
case T_SHORT:
return "S";//NOI18N
case T_INT:
return "I";//NOI18N
case T_LONG:
return "J";//NOI18N
case T_FLOAT:
return "F";//NOI18N
case T_DOUBLE:
return "D";//NOI18N
case TC_OBJECT:
return "Ljava/lang/Object;";//NOI18N
default:
throw new InsnError("bad element type");//NOI18N
}
}
/**
* Return the number of stack words required for a value of the specified
* type on the operand stack.
*/
public static int elementSize(int elementType) {
switch(elementType) {
case T_LONG:
case T_DOUBLE:
case T_TWOWORD:
return 2;
default:
return 1;
}
}
/**
* stackSig is a signature for a list of types on the JVM stack with the
* last type in the signature intended to be on the top of JVM stack.
* For each type in the signature, pushes an Integer objects identifying
* the types on top of the input Stack object.
*/
public static void computeStackTypes(String stackSig, Stack stack) {
for (int idx = 0; idx < stackSig.length(); idx++) {
int tp = 0;
switch(stackSig.charAt(idx)) {
case 'B':
case 'C':
case 'Z':
case 'S':
case 'I':
tp = T_INT;
break;
case 'F':
tp = T_FLOAT;
break;
case 'J':
tp = T_LONG;
break;
case 'D':
tp = T_DOUBLE;
break;
case '?':
tp = T_UNKNOWN;
break;
case 'W':
tp = T_WORD;
break;
case 'X':
tp = T_TWOWORD;
break;
case 'A':
/* This isn't a real type, but any object refrence */
tp = TC_OBJECT;
break;
case '[':
tp = TC_OBJECT;
while (stackSig.charAt(idx) == '[' || stackSig.charAt(idx) == ']')
idx++;
if (stackSig.charAt(idx) != 'L')
break;
/* fall through */
case 'L':
tp = TC_OBJECT;
idx = stackSig.indexOf(';', idx);
break;
default:
throw new InsnError("bad signature char");//NOI18N
}
stack.push(new Integer(tp));
}
}
/**
* stackSig is a signature for the types on the stack with the last
* type in the signature on the top of stack. idx is the index of
* the start of a valid signature type element. Return the index of
* the next element (which may be past the end of the string).
*/
public static int nextSigElement(String stackSig, int idx) {
switch(stackSig.charAt(idx)) {
case 'B':
case 'C':
case 'Z':
case 'S':
case 'I':
case 'F':
case 'J':
case 'D':
break;
case '[':
while (stackSig.charAt(idx) == '[' || stackSig.charAt(idx) == ']')
idx++;
if (stackSig.charAt(idx) != 'L')
break;
/* fall through */
case 'L':
idx = stackSig.indexOf(';', idx);
break;
default:
throw new InsnError("bad signature char");//NOI18N
}
idx++;
return idx;
}
/**
* classTranslations contains a set of mappings of class names.
* For any types within the input signature which appear as keys
* in the translation table, change the signature to replace the
* original type with the translation. Return a string containing
* the original signature with any translations applied.
*/
public static String remapTypes(String sig, Map classTranslations) {
/* Defer allocation of the string buffer until it's needed */
StringBuffer buf = null;
for (int idx = 0; idx < sig.length(); idx++) {
char c;
switch(c = sig.charAt(idx)) {
case '[':
/* An array - skip through the [] pairs, copying to buf if not null */
while ((c = sig.charAt(idx)) == '[' || c == ']') {
idx++;
if (buf != null)
buf.append(c);
}
/* If the next char isnt 'L', the next char is a simple type and
will be handled by the default 1 char translation */
if (sig.charAt(idx) != 'L')
break;
/* fall through to type name translation */
case 'L':
/* This is a type name */
idx++;
int endIdx = sig.indexOf(';', idx);
String typeName = sig.substring(idx, endIdx);
String mapTo = (String) classTranslations.get(typeName);
if (mapTo != null) {
/* This type needs translation - allocate the string buffer
now if needed and copy in all up to this type name. */
if (buf == null) {
buf = new StringBuffer(sig.length() + 20);
buf.append(sig.substring(0,idx-1));
}
typeName = mapTo;
}
if (buf != null) {
buf.append('L');
buf.append(typeName);
}
idx = endIdx;
c = ';';
break;
}
if (buf != null)
buf.append(c);
}
return (buf == null) ? sig : (buf.toString());
}
/**
* classTranslations contains a set of mappings of class names.
* Translate the class name (which may be an array class) according
* to the entries in the translation table.
* Return either the original string if no translation applies or
* else the translated string.
*/
public static String translateClass(
String cls, Map classTranslations) {
if (cls.charAt(0) == '[')
return remapTypes(cls, classTranslations);
else {
String mapTo = (String) classTranslations.get(cls);
if (mapTo != null)
return mapTo;
return cls;
}
}
/**
* Translates a VM type field signature into a user-format signature.
* Just a front for the two argument overload of this method.
*/
public static String userFieldSig(String vmSig) {
return userFieldSig(vmSig, 0);
}
/**
* Translates a VM type field signature into a user-format signature.
*/
public static String userFieldSig(String vmSig, int idx) {
String sigElement = "";//NOI18N
int arrayDims = 0;
boolean moreSig = true;
while (moreSig) {
moreSig = false;
char c = vmSig.charAt(idx);
switch (c) {
case 'B':
sigElement = "byte";//NOI18N
break;
case 'C':
sigElement = "char";//NOI18N
break;
case 'Z':
sigElement = "boolean";//NOI18N
break;
case 'S':
sigElement = "short";//NOI18N
break;
case 'I':
sigElement = "int";//NOI18N
break;
case 'F':
sigElement = "float";//NOI18N
break;
case 'J':
sigElement = "long";//NOI18N
break;
case 'D':
sigElement = "double";//NOI18N
break;
case 'V':
/* void isn't really valid as a field signature but this method
might be useful in implementing method signature conversion and
void is a valid return type. */
sigElement = "void";//NOI18N
break;
case '[':
idx++;
arrayDims++;
moreSig = true;
break;
case 'L':
int nextIdx = vmSig.indexOf(';', idx);
sigElement = vmSig.substring(idx+1,nextIdx).replace('/','.');
break;
default:
throw new InsnError("bad signature char");//NOI18N
}
}
/* If a non-array type, we already have the answer */
if (arrayDims == 0)
return sigElement;
/* array types need a little more work */
StringBuffer buf = new StringBuffer(sigElement.length() + 2 * arrayDims);
buf.append(sigElement);
while (arrayDims-- > 0)
buf.append("[]");//NOI18N
return buf.toString();
}
/**
* Produce a user consumable representation of a method argument list
* from the method signature. The return value is ignored.
*/
public static String userMethodArgs(String methodSig) {
/* This better be a method signature */
if (methodSig.charAt(0) != '(')
throw new InsnError("Invalid method signature");//NOI18N
StringBuffer buf = new StringBuffer();
buf.append('(');
int idx = 1;
boolean firstArg = true;
while (methodSig.charAt(idx) != ')') {
if (firstArg)
firstArg = false;
else
buf.append(", ");//NOI18N
buf.append(userFieldSig(methodSig, idx));
idx = nextSigElement(methodSig, idx);
}
buf.append(')');
return buf.toString();
}
}