1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178
179
180
181
182
183
184
185
186
187
188
189
190
191
192
193
194
195
196
197
|
/*
* Copyright (c) 2015, Oracle and/or its affiliates. All rights reserved.
*/
/*
* Licensed to the Apache Software Foundation (ASF) under one or more
* contributor license agreements. See the NOTICE file distributed with
* this work for additional information regarding copyright ownership.
* The ASF licenses this file to You 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: ForEach.java,v 1.2.4.1 2005/09/01 15:23:46 pvedula Exp $
*/
package com.sun.org.apache.xalan.internal.xsltc.compiler;
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.IFGT;
import com.sun.org.apache.bcel.internal.generic.InstructionHandle;
import com.sun.org.apache.bcel.internal.generic.InstructionList;
import com.sun.org.apache.xalan.internal.xsltc.compiler.util.ClassGenerator;
import com.sun.org.apache.xalan.internal.xsltc.compiler.util.ErrorMsg;
import com.sun.org.apache.xalan.internal.xsltc.compiler.util.MethodGenerator;
import com.sun.org.apache.xalan.internal.xsltc.compiler.util.NodeSetType;
import com.sun.org.apache.xalan.internal.xsltc.compiler.util.NodeType;
import com.sun.org.apache.xalan.internal.xsltc.compiler.util.ReferenceType;
import com.sun.org.apache.xalan.internal.xsltc.compiler.util.ResultTreeType;
import com.sun.org.apache.xalan.internal.xsltc.compiler.util.Type;
import com.sun.org.apache.xalan.internal.xsltc.compiler.util.TypeCheckError;
import com.sun.org.apache.xalan.internal.xsltc.compiler.util.Util;
import java.util.Iterator;
import java.util.Vector;
/**
* @author Jacek Ambroziak
* @author Santiago Pericas-Geertsen
* @author Morten Jorgensen
*/
final class ForEach extends Instruction {
private Expression _select;
private Type _type;
public void display(int indent) {
indent(indent);
Util.println("ForEach");
indent(indent + IndentIncrement);
Util.println("select " + _select.toString());
displayContents(indent + IndentIncrement);
}
public void parseContents(Parser parser) {
_select = parser.parseExpression(this, "select", null);
parseChildren(parser);
// make sure required attribute(s) have been set
if (_select.isDummy()) {
reportError(this, parser, ErrorMsg.REQUIRED_ATTR_ERR, "select");
}
}
public Type typeCheck(SymbolTable stable) throws TypeCheckError {
_type = _select.typeCheck(stable);
if (_type instanceof ReferenceType || _type instanceof NodeType) {
_select = new CastExpr(_select, Type.NodeSet);
typeCheckContents(stable);
return Type.Void;
}
if (_type instanceof NodeSetType||_type instanceof ResultTreeType) {
typeCheckContents(stable);
return Type.Void;
}
throw new TypeCheckError(this);
}
public void translate(ClassGenerator classGen, MethodGenerator methodGen) {
final ConstantPoolGen cpg = classGen.getConstantPool();
final InstructionList il = methodGen.getInstructionList();
// Save current node and current iterator on the stack
il.append(methodGen.loadCurrentNode());
il.append(methodGen.loadIterator());
// Collect sort objects associated with this instruction
final Vector sortObjects = new Vector();
Iterator<SyntaxTreeNode> children = elements();
while (children.hasNext()) {
final SyntaxTreeNode child = children.next();
if (child instanceof Sort) {
sortObjects.addElement(child);
}
}
if ((_type != null) && (_type instanceof ResultTreeType)) {
// Store existing DOM on stack - must be restored when loop is done
il.append(methodGen.loadDOM());
// <xsl:sort> cannot be applied to a result tree - issue warning
if (sortObjects.size() > 0) {
ErrorMsg msg = new ErrorMsg(ErrorMsg.RESULT_TREE_SORT_ERR,this);
getParser().reportError(WARNING, msg);
}
// Put the result tree on the stack (DOM)
_select.translate(classGen, methodGen);
// Get an iterator for the whole DOM - excluding the root node
_type.translateTo(classGen, methodGen, Type.NodeSet);
// Store the result tree as the default DOM
il.append(SWAP);
il.append(methodGen.storeDOM());
}
else {
// Compile node iterator
if (sortObjects.size() > 0) {
Sort.translateSortIterator(classGen, methodGen,
_select, sortObjects);
}
else {
_select.translate(classGen, methodGen);
}
if (_type instanceof ReferenceType == false) {
il.append(methodGen.loadContextNode());
il.append(methodGen.setStartNode());
}
}
// Overwrite current iterator
il.append(methodGen.storeIterator());
// Give local variables (if any) default values before starting loop
initializeVariables(classGen, methodGen);
final BranchHandle nextNode = il.append(new GOTO(null));
final InstructionHandle loop = il.append(NOP);
translateContents(classGen, methodGen);
nextNode.setTarget(il.append(methodGen.loadIterator()));
il.append(methodGen.nextNode());
il.append(DUP);
il.append(methodGen.storeCurrentNode());
il.append(new IFGT(loop));
// Restore current DOM (if result tree was used instead for this loop)
if ((_type != null) && (_type instanceof ResultTreeType)) {
il.append(methodGen.storeDOM());
}
// Restore current node and current iterator from the stack
il.append(methodGen.storeIterator());
il.append(methodGen.storeCurrentNode());
}
/**
* The code that is generated by nested for-each loops can appear to some
* JVMs as if it is accessing un-initialized variables. We must add some
* code that pushes the default variable value on the stack and pops it
* into the variable slot. This is done by the Variable.initialize()
* method. The code that we compile for this loop looks like this:
*
* initialize iterator
* initialize variables <-- HERE!!!
* goto Iterate
* Loop: :
* : (code for <xsl:for-each> contents)
* :
* Iterate: node = iterator.next();
* if (node != END) goto Loop
*/
public void initializeVariables(ClassGenerator classGen,
MethodGenerator methodGen) {
final int n = elementCount();
for (int i = 0; i < n; i++) {
final SyntaxTreeNode child = getContents().get(i);
if (child instanceof Variable) {
Variable var = (Variable)child;
var.initialize(classGen, methodGen);
}
}
}
}
|
