javassist.compiler.JvstTypeChecker Maven / Gradle / Ivy
Go to download
Show more of this group Show more artifacts with this name
Show all versions of ehcache Show documentation
Show all versions of ehcache Show documentation
Ehcache is an open source, standards-based cache used to boost performance,
offload the database and simplify scalability. Ehcache is robust, proven and full-featured and
this has made it the most widely-used Java-based cache.
/*
* 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 javassist.compiler;
import javassist.*;
import javassist.compiler.ast.*;
/* Type checker accepting extended Java syntax for Javassist.
*/
public class JvstTypeChecker extends TypeChecker {
private JvstCodeGen codeGen;
public JvstTypeChecker(CtClass cc, ClassPool cp, JvstCodeGen gen) {
super(cc, cp);
codeGen = gen;
}
/* If the type of the expression compiled last is void,
* add ACONST_NULL and change exprType, arrayDim, className.
*/
public void addNullIfVoid() {
if (exprType == VOID) {
exprType = CLASS;
arrayDim = 0;
className = jvmJavaLangObject;
}
}
/* To support $args, $sig, and $type.
* $args is an array of parameter list.
*/
public void atMember(Member mem) throws CompileError {
String name = mem.get();
if (name.equals(codeGen.paramArrayName)) {
exprType = CLASS;
arrayDim = 1;
className = jvmJavaLangObject;
}
else if (name.equals(JvstCodeGen.sigName)) {
exprType = CLASS;
arrayDim = 1;
className = "java/lang/Class";
}
else if (name.equals(JvstCodeGen.dollarTypeName)
|| name.equals(JvstCodeGen.clazzName)) {
exprType = CLASS;
arrayDim = 0;
className = "java/lang/Class";
}
else
super.atMember(mem);
}
protected void atFieldAssign(Expr expr, int op, ASTree left, ASTree right)
throws CompileError
{
if (left instanceof Member
&& ((Member)left).get().equals(codeGen.paramArrayName)) {
right.accept(this);
CtClass[] params = codeGen.paramTypeList;
if (params == null)
return;
int n = params.length;
for (int i = 0; i < n; ++i)
compileUnwrapValue(params[i]);
}
else
super.atFieldAssign(expr, op, left, right);
}
public void atCastExpr(CastExpr expr) throws CompileError {
ASTList classname = expr.getClassName();
if (classname != null && expr.getArrayDim() == 0) {
ASTree p = classname.head();
if (p instanceof Symbol && classname.tail() == null) {
String typename = ((Symbol)p).get();
if (typename.equals(codeGen.returnCastName)) {
atCastToRtype(expr);
return;
}
else if (typename.equals(JvstCodeGen.wrapperCastName)) {
atCastToWrapper(expr);
return;
}
}
}
super.atCastExpr(expr);
}
/**
* Inserts a cast operator to the return type.
* If the return type is void, this does nothing.
*/
protected void atCastToRtype(CastExpr expr) throws CompileError {
CtClass returnType = codeGen.returnType;
expr.getOprand().accept(this);
if (exprType == VOID || CodeGen.isRefType(exprType) || arrayDim > 0)
compileUnwrapValue(returnType);
else if (returnType instanceof CtPrimitiveType) {
CtPrimitiveType pt = (CtPrimitiveType)returnType;
int destType = MemberResolver.descToType(pt.getDescriptor());
exprType = destType;
arrayDim = 0;
className = null;
}
}
protected void atCastToWrapper(CastExpr expr) throws CompileError {
expr.getOprand().accept(this);
if (CodeGen.isRefType(exprType) || arrayDim > 0)
return; // Object type. do nothing.
CtClass clazz = resolver.lookupClass(exprType, arrayDim, className);
if (clazz instanceof CtPrimitiveType) {
exprType = CLASS;
arrayDim = 0;
className = jvmJavaLangObject;
}
}
/* Delegates to a ProcHandler object if the method call is
* $proceed(). It may process $cflow().
*/
public void atCallExpr(CallExpr expr) throws CompileError {
ASTree method = expr.oprand1();
if (method instanceof Member) {
String name = ((Member)method).get();
if (codeGen.procHandler != null
&& name.equals(codeGen.proceedName)) {
codeGen.procHandler.setReturnType(this,
(ASTList)expr.oprand2());
return;
}
else if (name.equals(JvstCodeGen.cflowName)) {
atCflow((ASTList)expr.oprand2());
return;
}
}
super.atCallExpr(expr);
}
/* To support $cflow().
*/
protected void atCflow(ASTList cname) throws CompileError {
exprType = INT;
arrayDim = 0;
className = null;
}
/* To support $$. ($$) is equivalent to ($1, ..., $n).
* It can be used only as a parameter list of method call.
*/
public boolean isParamListName(ASTList args) {
if (codeGen.paramTypeList != null
&& args != null && args.tail() == null) {
ASTree left = args.head();
return (left instanceof Member
&& ((Member)left).get().equals(codeGen.paramListName));
}
else
return false;
}
public int getMethodArgsLength(ASTList args) {
String pname = codeGen.paramListName;
int n = 0;
while (args != null) {
ASTree a = args.head();
if (a instanceof Member && ((Member)a).get().equals(pname)) {
if (codeGen.paramTypeList != null)
n += codeGen.paramTypeList.length;
}
else
++n;
args = args.tail();
}
return n;
}
public void atMethodArgs(ASTList args, int[] types, int[] dims,
String[] cnames) throws CompileError {
CtClass[] params = codeGen.paramTypeList;
String pname = codeGen.paramListName;
int i = 0;
while (args != null) {
ASTree a = args.head();
if (a instanceof Member && ((Member)a).get().equals(pname)) {
if (params != null) {
int n = params.length;
for (int k = 0; k < n; ++k) {
CtClass p = params[k];
setType(p);
types[i] = exprType;
dims[i] = arrayDim;
cnames[i] = className;
++i;
}
}
}
else {
a.accept(this);
types[i] = exprType;
dims[i] = arrayDim;
cnames[i] = className;
++i;
}
args = args.tail();
}
}
/* called by Javac#recordSpecialProceed().
*/
void compileInvokeSpecial(ASTree target, String classname,
String methodname, String descriptor,
ASTList args)
throws CompileError
{
target.accept(this);
int nargs = getMethodArgsLength(args);
atMethodArgs(args, new int[nargs], new int[nargs],
new String[nargs]);
setReturnType(descriptor);
addNullIfVoid();
}
protected void compileUnwrapValue(CtClass type) throws CompileError
{
if (type == CtClass.voidType)
addNullIfVoid();
else
setType(type);
}
/* Sets exprType, arrayDim, and className;
* If type is void, then this method does nothing.
*/
public void setType(CtClass type) throws CompileError {
setType(type, 0);
}
private void setType(CtClass type, int dim) throws CompileError {
if (type.isPrimitive()) {
CtPrimitiveType pt = (CtPrimitiveType)type;
exprType = MemberResolver.descToType(pt.getDescriptor());
arrayDim = dim;
className = null;
}
else if (type.isArray())
try {
setType(type.getComponentType(), dim + 1);
}
catch (NotFoundException e) {
throw new CompileError("undefined type: " + type.getName());
}
else {
exprType = CLASS;
arrayDim = dim;
className = MemberResolver.javaToJvmName(type.getName());
}
}
}