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feilong is a suite of core and expanded libraries that include utility classes, http, excel,cvs, io classes, and much much more.
/*
* Javassist, a Java-bytecode translator toolkit.
* Copyright (C) 1999- Shigeru Chiba. All Rights Reserved.
*
* The contents of this file are subject to the Mozilla Public License Version
* 1.1 (the "License"); you may not use this file except in compliance with
* the License. Alternatively, the contents of this file may be used under
* the terms of the GNU Lesser General Public License Version 2.1 or later,
* or the Apache License Version 2.0.
*
* Software distributed under the License is distributed on an "AS IS" basis,
* WITHOUT WARRANTY OF ANY KIND, either express or implied. See the License
* for the specific language governing rights and limitations under the
* License.
*/
package com.feilong.lib.javassist.expr;
import java.util.LinkedList;
import java.util.List;
import com.feilong.lib.javassist.CannotCompileException;
import com.feilong.lib.javassist.ClassPool;
import com.feilong.lib.javassist.CtBehavior;
import com.feilong.lib.javassist.CtClass;
import com.feilong.lib.javassist.CtConstructor;
import com.feilong.lib.javassist.CtPrimitiveType;
import com.feilong.lib.javassist.NotFoundException;
import com.feilong.lib.javassist.bytecode.AccessFlag;
import com.feilong.lib.javassist.bytecode.BadBytecode;
import com.feilong.lib.javassist.bytecode.Bytecode;
import com.feilong.lib.javassist.bytecode.ClassFile;
import com.feilong.lib.javassist.bytecode.CodeAttribute;
import com.feilong.lib.javassist.bytecode.CodeIterator;
import com.feilong.lib.javassist.bytecode.ConstPool;
import com.feilong.lib.javassist.bytecode.ExceptionTable;
import com.feilong.lib.javassist.bytecode.ExceptionsAttribute;
import com.feilong.lib.javassist.bytecode.MethodInfo;
import com.feilong.lib.javassist.bytecode.Opcode;
import com.feilong.lib.javassist.compiler.Javac;
/**
* Expression.
*/
public abstract class Expr implements Opcode{
int currentPos;
CodeIterator iterator;
CtClass thisClass;
MethodInfo thisMethod;
boolean edited;
int maxLocals, maxStack;
static final String javaLangObject = "java.lang.Object";
/**
* Undocumented constructor. Do not use; internal-use only.
*/
protected Expr(int pos, CodeIterator i, CtClass declaring, MethodInfo m){
currentPos = pos;
iterator = i;
thisClass = declaring;
thisMethod = m;
}
/**
* Returns the class that declares the method enclosing
* this expression.
*
* @since 3.7
*/
public CtClass getEnclosingClass(){
return thisClass;
}
protected final ConstPool getConstPool(){
return thisMethod.getConstPool();
}
protected final boolean edited(){
return edited;
}
protected final int locals(){
return maxLocals;
}
protected final int stack(){
return maxStack;
}
/**
* Returns true if this method is static.
*/
protected final boolean withinStatic(){
return (thisMethod.getAccessFlags() & AccessFlag.STATIC) != 0;
}
/**
* Returns the constructor or method containing the expression.
*/
public CtBehavior where(){
MethodInfo mi = thisMethod;
CtBehavior[] cb = thisClass.getDeclaredBehaviors();
for (int i = cb.length - 1; i >= 0; --i){
if (cb[i].getMethodInfo2() == mi){
return cb[i];
}
}
CtConstructor init = thisClass.getClassInitializer();
if (init != null && init.getMethodInfo2() == mi){
return init;
}
/*
* getDeclaredBehaviors() returns a list of methods/constructors.
* Although the list is cached in a CtClass object, it might be
* recreated for some reason. Thus, the member name and the signature
* must be also checked.
*/
for (int i = cb.length - 1; i >= 0; --i){
if (thisMethod.getName().equals(cb[i].getMethodInfo2().getName())
&& thisMethod.getDescriptor().equals(cb[i].getMethodInfo2().getDescriptor())){
return cb[i];
}
}
throw new RuntimeException("fatal: not found");
}
/**
* Returns the list of exceptions that the expression may throw. This list
* includes both the exceptions that the try-catch statements including the
* expression can catch and the exceptions that the throws declaration
* allows the method to throw.
*/
public CtClass[] mayThrow(){
ClassPool pool = thisClass.getClassPool();
ConstPool cp = thisMethod.getConstPool();
List list = new LinkedList<>();
try{
CodeAttribute ca = thisMethod.getCodeAttribute();
ExceptionTable et = ca.getExceptionTable();
int pos = currentPos;
int n = et.size();
for (int i = 0; i < n; ++i){
if (et.startPc(i) <= pos && pos < et.endPc(i)){
int t = et.catchType(i);
if (t > 0){
try{
addClass(list, pool.get(cp.getClassInfo(t)));
}catch (NotFoundException e){}
}
}
}
}catch (NullPointerException e){}
ExceptionsAttribute ea = thisMethod.getExceptionsAttribute();
if (ea != null){
String[] exceptions = ea.getExceptions();
if (exceptions != null){
int n = exceptions.length;
for (int i = 0; i < n; ++i){
try{
addClass(list, pool.get(exceptions[i]));
}catch (NotFoundException e){}
}
}
}
return list.toArray(new CtClass[list.size()]);
}
private static void addClass(List list,CtClass c){
if (list.contains(c)){
return;
}
list.add(c);
}
/**
* Returns the index of the bytecode corresponding to the expression. It is
* the index into the byte array containing the Java bytecode that
* implements the method.
*/
public int indexOfBytecode(){
return currentPos;
}
/**
* Returns the line number of the source line containing the expression.
*
* @return -1 if this information is not available.
*/
public int getLineNumber(){
return thisMethod.getLineNumber(currentPos);
}
/**
* Returns the source file containing the expression.
*
* @return null if this information is not available.
*/
public String getFileName(){
ClassFile cf = thisClass.getClassFile2();
if (cf == null){
return null;
}
return cf.getSourceFile();
}
static final boolean checkResultValue(CtClass retType,String prog) throws CannotCompileException{
/*
* Is $_ included in the source code?
*/
boolean hasIt = (prog.indexOf(Javac.resultVarName) >= 0);
if (!hasIt && retType != CtClass.voidType){
throw new CannotCompileException("the resulting value is not stored in " + Javac.resultVarName);
}
return hasIt;
}
/*
* If isStaticCall is true, null is assigned to $0. So $0 must be declared
* by calling Javac.recordParams().
*
* After executing this method, the current stack depth might be less than
* 0.
*/
static final void storeStack(CtClass[] params,boolean isStaticCall,int regno,Bytecode bytecode){
storeStack0(0, params.length, params, regno + 1, bytecode);
if (isStaticCall){
bytecode.addOpcode(ACONST_NULL);
}
bytecode.addAstore(regno);
}
private static void storeStack0(int i,int n,CtClass[] params,int regno,Bytecode bytecode){
if (i >= n){
return;
}
CtClass c = params[i];
int size;
if (c instanceof CtPrimitiveType){
size = ((CtPrimitiveType) c).getDataSize();
}else{
size = 1;
}
storeStack0(i + 1, n, params, regno + size, bytecode);
bytecode.addStore(regno, c);
}
// The implementation of replace() should call thisClass.checkModify()
// so that isModify() will return true. Otherwise, thisClass.classfile
// might be released during compilation and the compiler might generate
// bytecode with a wrong copy of ConstPool.
/**
* Replaces this expression with the bytecode derived from
* the given source text.
*
* @param statement
* a Java statement except try-catch.
*/
public abstract void replace(String statement) throws CannotCompileException;
/**
* Replaces this expression with the bytecode derived from
* the given source text and ExprEditor.
*
* @param statement
* a Java statement except try-catch.
* @param recursive
* if not null, the substituted bytecode
* is recursively processed by the given
* ExprEditor.
* @since 3.1
*/
public void replace(String statement,ExprEditor recursive) throws CannotCompileException{
replace(statement);
if (recursive != null){
runEditor(recursive, iterator);
}
}
protected void replace0(int pos,Bytecode bytecode,int size) throws BadBytecode{
byte[] code = bytecode.get();
edited = true;
int gap = code.length - size;
for (int i = 0; i < size; ++i){
iterator.writeByte(NOP, pos + i);
}
if (gap > 0){
pos = iterator.insertGapAt(pos, gap, false).position;
}
iterator.write(code, pos);
iterator.insert(bytecode.getExceptionTable(), pos);
maxLocals = bytecode.getMaxLocals();
maxStack = bytecode.getMaxStack();
}
protected void runEditor(ExprEditor ed,CodeIterator oldIterator) throws CannotCompileException{
CodeAttribute codeAttr = oldIterator.get();
int orgLocals = codeAttr.getMaxLocals();
int orgStack = codeAttr.getMaxStack();
int newLocals = locals();
codeAttr.setMaxStack(stack());
codeAttr.setMaxLocals(newLocals);
ExprEditor.LoopContext context = new ExprEditor.LoopContext(newLocals);
int size = oldIterator.getCodeLength();
int endPos = oldIterator.lookAhead();
oldIterator.move(currentPos);
if (ed.doit(thisClass, thisMethod, context, oldIterator, endPos)){
edited = true;
}
oldIterator.move(endPos + oldIterator.getCodeLength() - size);
codeAttr.setMaxLocals(orgLocals);
codeAttr.setMaxStack(orgStack);
maxLocals = context.maxLocals;
maxStack += context.maxStack;
}
}