/*
* Copyright 2001-2004 The Apache Software Foundation.
*
* Licensed under the Apache License, Version 2.0 (the "License");
* you may not use this file except in compliance with the License.
* You may obtain a copy of the License at
*
* http://www.apache.org/licenses/LICENSE-2.0
*
* Unless required by applicable law or agreed to in writing, software
* distributed under the License is distributed on an "AS IS" BASIS,
* WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
* See the License for the specific language governing permissions and
* limitations under the License.
*/
/*
* $Id: NodeSetType.java,v 1.2.4.1 2005/09/05 11:21:45 pvedula Exp $
*/
package com.sun.org.apache.xalan.internal.xsltc.compiler.util;
import com.sun.org.apache.bcel.internal.generic.ALOAD;
import com.sun.org.apache.bcel.internal.generic.ASTORE;
import com.sun.org.apache.bcel.internal.generic.BranchHandle;
import com.sun.org.apache.bcel.internal.generic.ConstantPoolGen;
import com.sun.org.apache.bcel.internal.generic.GOTO;
import com.sun.org.apache.bcel.internal.generic.IFLT;
import com.sun.org.apache.bcel.internal.generic.INVOKEINTERFACE;
import com.sun.org.apache.bcel.internal.generic.INVOKESTATIC;
import com.sun.org.apache.bcel.internal.generic.Instruction;
import com.sun.org.apache.bcel.internal.generic.InstructionList;
import com.sun.org.apache.bcel.internal.generic.PUSH;
import com.sun.org.apache.xalan.internal.xsltc.compiler.Constants;
import com.sun.org.apache.xalan.internal.xsltc.compiler.FlowList;
/**
* @author Jacek Ambroziak
* @author Santiago Pericas-Geertsen
*/
public final class NodeSetType extends Type {
protected NodeSetType() {}
public String toString() {
return "node-set";
}
public boolean identicalTo(Type other) {
return this == other;
}
public String toSignature() {
return NODE_ITERATOR_SIG;
}
public com.sun.org.apache.bcel.internal.generic.Type toJCType() {
return new com.sun.org.apache.bcel.internal.generic.ObjectType(NODE_ITERATOR);
}
/**
* Translates a node-set into an object of internal type
* <code>type</code>. The translation to int is undefined
* since node-sets are always converted to
* reals in arithmetic expressions.
*
* @see com.sun.org.apache.xalan.internal.xsltc.compiler.util.Type#translateTo
*/
public void translateTo(ClassGenerator classGen, MethodGenerator methodGen,
Type type) {
if (type == Type.String) {
translateTo(classGen, methodGen, (StringType) type);
}
else if (type == Type.Boolean) {
translateTo(classGen, methodGen, (BooleanType) type);
}
else if (type == Type.Real) {
translateTo(classGen, methodGen, (RealType) type);
}
else if (type == Type.Node) {
translateTo(classGen, methodGen, (NodeType) type);
}
else if (type == Type.Reference) {
translateTo(classGen, methodGen, (ReferenceType) type);
}
else if (type == Type.Object) {
translateTo(classGen, methodGen, (ObjectType) type);
}
else {
ErrorMsg err = new ErrorMsg(ErrorMsg.DATA_CONVERSION_ERR,
toString(), type.toString());
classGen.getParser().reportError(Constants.FATAL, err);
}
}
/**
* Translates an external Java Class into an internal type.
* Expects the Java object on the stack, pushes the internal type
*/
public void translateFrom(ClassGenerator classGen,
MethodGenerator methodGen, Class clazz)
{
InstructionList il = methodGen.getInstructionList();
ConstantPoolGen cpg = classGen.getConstantPool();
if (clazz.getName().equals("org.w3c.dom.NodeList")) {
// w3c NodeList is on the stack from the external Java function call.
// call BasisFunction to consume NodeList and leave Iterator on
// the stack.
il.append(classGen.loadTranslet()); // push translet onto stack
il.append(methodGen.loadDOM()); // push DOM onto stack
final int convert = cpg.addMethodref(BASIS_LIBRARY_CLASS,
"nodeList2Iterator",
"("
+ "Lorg/w3c/dom/NodeList;"
+ TRANSLET_INTF_SIG
+ DOM_INTF_SIG
+ ")" + NODE_ITERATOR_SIG );
il.append(new INVOKESTATIC(convert));
}
else if (clazz.getName().equals("org.w3c.dom.Node")) {
// w3c Node is on the stack from the external Java function call.
// call BasisLibrary.node2Iterator() to consume Node and leave
// Iterator on the stack.
il.append(classGen.loadTranslet()); // push translet onto stack
il.append(methodGen.loadDOM()); // push DOM onto stack
final int convert = cpg.addMethodref(BASIS_LIBRARY_CLASS,
"node2Iterator",
"("
+ "Lorg/w3c/dom/Node;"
+ TRANSLET_INTF_SIG
+ DOM_INTF_SIG
+ ")" + NODE_ITERATOR_SIG );
il.append(new INVOKESTATIC(convert));
}
else {
ErrorMsg err = new ErrorMsg(ErrorMsg.DATA_CONVERSION_ERR,
toString(), clazz.getName());
classGen.getParser().reportError(Constants.FATAL, err);
}
}
/**
* Translates a node-set into a synthesized boolean.
* The boolean value of a node-set is "true" if non-empty
* and "false" otherwise. Notice that the
* function getFirstNode() is called in translateToDesynthesized().
*
* @see com.sun.org.apache.xalan.internal.xsltc.compiler.util.Type#translateTo
*/
public void translateTo(ClassGenerator classGen, MethodGenerator methodGen,
BooleanType type) {
final InstructionList il = methodGen.getInstructionList();
FlowList falsel = translateToDesynthesized(classGen, methodGen, type);
il.append(ICONST_1);
final BranchHandle truec = il.append(new GOTO(null));
falsel.backPatch(il.append(ICONST_0));
truec.setTarget(il.append(NOP));
}
/**
* Translates a node-set into a string. The string value of a node-set is
* value of its first element.
*
* @see com.sun.org.apache.xalan.internal.xsltc.compiler.util.Type#translateTo
*/
public void translateTo(ClassGenerator classGen, MethodGenerator methodGen,
StringType type) {
final InstructionList il = methodGen.getInstructionList();
getFirstNode(classGen, methodGen);
il.append(DUP);
final BranchHandle falsec = il.append(new IFLT(null));
Type.Node.translateTo(classGen, methodGen, type);
final BranchHandle truec = il.append(new GOTO(null));
falsec.setTarget(il.append(POP));
il.append(new PUSH(classGen.getConstantPool(), ""));
truec.setTarget(il.append(NOP));
}
/**
* Expects a node-set on the stack and pushes a real.
* First the node-set is converted to string, and from string to real.
*
* @see com.sun.org.apache.xalan.internal.xsltc.compiler.util.Type#translateTo
*/
public void translateTo(ClassGenerator classGen, MethodGenerator methodGen,
RealType type) {
translateTo(classGen, methodGen, Type.String);
Type.String.translateTo(classGen, methodGen, Type.Real);
}
/**
* Expects a node-set on the stack and pushes a node.
*
* @see com.sun.org.apache.xalan.internal.xsltc.compiler.util.Type#translateTo
*/
public void translateTo(ClassGenerator classGen, MethodGenerator methodGen,
NodeType type) {
getFirstNode(classGen, methodGen);
}
/**
* Subsume node-set into ObjectType.
*
* @see com.sun.org.apache.xalan.internal.xsltc.compiler.util.Type#translateTo
*/
public void translateTo(ClassGenerator classGen, MethodGenerator methodGen,
ObjectType type) {
methodGen.getInstructionList().append(NOP);
}
/**
* Translates a node-set into a non-synthesized boolean. It does not
* push a 0 or a 1 but instead returns branchhandle list to be appended
* to the false list.
*
* @see com.sun.org.apache.xalan.internal.xsltc.compiler.util.Type#translateToDesynthesized
*/
public FlowList translateToDesynthesized(ClassGenerator classGen,
MethodGenerator methodGen,
BooleanType type) {
final InstructionList il = methodGen.getInstructionList();
getFirstNode(classGen, methodGen);
return new FlowList(il.append(new IFLT(null)));
}
/**
* Expects a node-set on the stack and pushes a boxed node-set.
* Node sets are already boxed so the translation is just a NOP.
*
* @see com.sun.org.apache.xalan.internal.xsltc.compiler.util.Type#translateTo
*/
public void translateTo(ClassGenerator classGen, MethodGenerator methodGen,
ReferenceType type) {
methodGen.getInstructionList().append(NOP);
}
/**
* Translates a node-set into the Java type denoted by <code>clazz</code>.
* Expects a node-set on the stack and pushes an object of the appropriate
* type after coercion.
*/
public void translateTo(ClassGenerator classGen, MethodGenerator methodGen,
Class clazz) {
final ConstantPoolGen cpg = classGen.getConstantPool();
final InstructionList il = methodGen.getInstructionList();
final String className = clazz.getName();
il.append(methodGen.loadDOM());
il.append(SWAP);
if (className.equals("org.w3c.dom.Node")) {
int index = cpg.addInterfaceMethodref(DOM_INTF,
MAKE_NODE,
MAKE_NODE_SIG2);
il.append(new INVOKEINTERFACE(index, 2));
}
else if (className.equals("org.w3c.dom.NodeList") ||
className.equals("java.lang.Object")) {
int index = cpg.addInterfaceMethodref(DOM_INTF,
MAKE_NODE_LIST,
MAKE_NODE_LIST_SIG2);
il.append(new INVOKEINTERFACE(index, 2));
}
else if (className.equals("java.lang.String")) {
int next = cpg.addInterfaceMethodref(NODE_ITERATOR,
"next", "()I");
int index = cpg.addInterfaceMethodref(DOM_INTF,
GET_NODE_VALUE,
"(I)"+STRING_SIG);
// Get next node from the iterator
il.append(new INVOKEINTERFACE(next, 1));
// Get the node's string value (from the DOM)
il.append(new INVOKEINTERFACE(index, 2));
}
else {
ErrorMsg err = new ErrorMsg(ErrorMsg.DATA_CONVERSION_ERR,
toString(), className);
classGen.getParser().reportError(Constants.FATAL, err);
}
}
/**
* Some type conversions require gettting the first node from the node-set.
* This function is defined to avoid code repetition.
*/
private void getFirstNode(ClassGenerator classGen, MethodGenerator methodGen) {
final ConstantPoolGen cpg = classGen.getConstantPool();
final InstructionList il = methodGen.getInstructionList();
il.append(new INVOKEINTERFACE(cpg.addInterfaceMethodref(NODE_ITERATOR,
NEXT,
NEXT_SIG), 1));
}
/**
* Translates an object of this type to its boxed representation.
*/
public void translateBox(ClassGenerator classGen,
MethodGenerator methodGen) {
translateTo(classGen, methodGen, Type.Reference);
}
/**
* Translates an object of this type to its unboxed representation.
*/
public void translateUnBox(ClassGenerator classGen,
MethodGenerator methodGen) {
methodGen.getInstructionList().append(NOP);
}
/**
* Returns the class name of an internal type's external representation.
*/
public String getClassName() {
return(NODE_ITERATOR);
}
public Instruction LOAD(int slot) {
return new ALOAD(slot);
}
public Instruction STORE(int slot) {
return new ASTORE(slot);
}
}
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