1 /*
2 * Copyright (c) 2016, Oracle and/or its affiliates. All rights reserved.
3 */
4 /*
5 * Copyright 2001-2004 The Apache Software Foundation.
6 *
7 * Licensed under the Apache License, Version 2.0 (the "License");
8 * you may not use this file except in compliance with the License.
9 * You may obtain a copy of the License at
10 *
11 * http://www.apache.org/licenses/LICENSE-2.0
12 *
13 * Unless required by applicable law or agreed to in writing, software
14 * distributed under the License is distributed on an "AS IS" BASIS,
15 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
16 * See the License for the specific language governing permissions and
17 * limitations under the License.
18 */
19
20 package com.sun.org.apache.xalan.internal.xsltc.compiler;
21
22 import com.sun.org.apache.bcel.internal.generic.ALOAD;
23 import com.sun.org.apache.bcel.internal.generic.ASTORE;
24 import com.sun.org.apache.bcel.internal.generic.CHECKCAST;
25 import com.sun.org.apache.bcel.internal.generic.ConstantPoolGen;
26 import com.sun.org.apache.bcel.internal.generic.INVOKEINTERFACE;
27 import com.sun.org.apache.bcel.internal.generic.INVOKEVIRTUAL;
28 import com.sun.org.apache.bcel.internal.generic.InstructionList;
29 import com.sun.org.apache.bcel.internal.generic.LocalVariableGen;
30 import com.sun.org.apache.bcel.internal.generic.PUSH;
31 import com.sun.org.apache.xalan.internal.xsltc.compiler.util.ClassGenerator;
32 import com.sun.org.apache.xalan.internal.xsltc.compiler.util.ErrorMsg;
33 import com.sun.org.apache.xalan.internal.xsltc.compiler.util.MethodGenerator;
34 import com.sun.org.apache.xalan.internal.xsltc.compiler.util.ReferenceType;
35 import com.sun.org.apache.xalan.internal.xsltc.compiler.util.Type;
36 import com.sun.org.apache.xalan.internal.xsltc.compiler.util.TypeCheckError;
37 import com.sun.org.apache.xalan.internal.xsltc.compiler.util.Util;
38 import com.sun.org.apache.xml.internal.utils.XML11Char;
39
40 /**
41 * @author Jacek Ambroziak
42 * @author Santiago Pericas-Geertsen
43 * @author Morten Jorgensen
44 * @author John Howard <JohnH@schemasoft.com>
45 */
46 final class WithParam extends Instruction {
47
48 /**
49 * Parameter's name.
50 */
51 private QName _name;
52
53 /**
54 * The escaped qname of the with-param.
55 */
56 protected String _escapedName;
57
58 /**
59 * Parameter's default value.
60 */
61 private Expression _select;
62
63 /**
64 * Reference to JVM variable holding temporary result tree.
65 */
66 private LocalVariableGen _domAdapter;
67
68 /**
69 * %OPT% This is set to true when the WithParam is used in a CallTemplate
70 * for a simple named template. If this is true, the parameters are
71 * passed to the named template through method arguments rather than
72 * using the expensive Translet.addParameter() call.
73 */
74 private boolean _doParameterOptimization = false;
75
76 /**
77 * Displays the contents of this element
78 */
79 public void display(int indent) {
80 indent(indent);
81 Util.println("with-param " + _name);
82 if (_select != null) {
83 indent(indent + IndentIncrement);
84 Util.println("select " + _select.toString());
85 }
86 displayContents(indent + IndentIncrement);
87 }
88
89 /**
90 * Returns the escaped qname of the parameter
91 */
92 public String getEscapedName() {
93 return _escapedName;
94 }
95
96 /**
97 * Return the name of this WithParam.
98 */
99 public QName getName() {
100 return _name;
101 }
102
103 /**
104 * Set the name of the variable or paremeter. Escape all special chars.
105 */
106 public void setName(QName name) {
107 _name = name;
108 _escapedName = Util.escape(name.getStringRep());
109 }
110
111 /**
112 * Set the do parameter optimization flag
113 */
114 public void setDoParameterOptimization(boolean flag) {
115 _doParameterOptimization = flag;
116 }
117
118 /**
119 * The contents of a <xsl:with-param> elements are either in the element's
120 * 'select' attribute (this has precedence) or in the element body.
121 */
122 public void parseContents(Parser parser) {
123 final String name = getAttribute("name");
124 if (name.length() > 0) {
125 if (!XML11Char.isXML11ValidQName(name)) {
126 ErrorMsg err = new ErrorMsg(ErrorMsg.INVALID_QNAME_ERR, name,
127 this);
128 parser.reportError(Constants.ERROR, err);
129 }
130 setName(parser.getQNameIgnoreDefaultNs(name));
131 }
132 else {
133 reportError(this, parser, ErrorMsg.REQUIRED_ATTR_ERR, "name");
134 }
135
136 final String select = getAttribute("select");
137 if (select.length() > 0) {
138 _select = parser.parseExpression(this, "select", null);
139 }
140
141 parseChildren(parser);
142 }
143
144 /**
145 * Type-check either the select attribute or the element body, depending
146 * on which is in use.
147 */
148 public Type typeCheck(SymbolTable stable) throws TypeCheckError {
149 if (_select != null) {
150 final Type tselect = _select.typeCheck(stable);
151 if (tselect instanceof ReferenceType == false) {
152 _select = new CastExpr(_select, Type.Reference);
153 }
154 }
155 else {
156 typeCheckContents(stable);
157 }
158 return Type.Void;
159 }
160
161 /**
162 * Compile the value of the parameter, which is either in an expression in
163 * a 'select' attribute, or in the with-param element's body
164 */
165 public void translateValue(ClassGenerator classGen,
166 MethodGenerator methodGen) {
167 // Compile expression is 'select' attribute if present
168 if (_select != null) {
169 _select.translate(classGen, methodGen);
170 _select.startIterator(classGen, methodGen);
171 }
172 // If not, compile result tree from parameter body if present.
173 // Store result tree into local variable for releasing it later
174 else if (hasContents()) {
175 final InstructionList il = methodGen.getInstructionList();
176 compileResultTree(classGen, methodGen);
177 _domAdapter = methodGen.addLocalVariable2("@" + _escapedName, Type.ResultTree.toJCType(), il.getEnd());
178 il.append(DUP);
179 il.append(new ASTORE(_domAdapter.getIndex()));
180 }
181 // If neither are present then store empty string in parameter slot
182 else {
183 final ConstantPoolGen cpg = classGen.getConstantPool();
184 final InstructionList il = methodGen.getInstructionList();
185 il.append(new PUSH(cpg, Constants.EMPTYSTRING));
186 }
187 }
188
189 /**
190 * This code generates a sequence of bytecodes that call the
191 * addParameter() method in AbstractTranslet. The method call will add
192 * (or update) the parameter frame with the new parameter value.
193 */
194 public void translate(ClassGenerator classGen, MethodGenerator methodGen) {
195 final ConstantPoolGen cpg = classGen.getConstantPool();
196 final InstructionList il = methodGen.getInstructionList();
197
198 // Translate the value and put it on the stack
199 if (_doParameterOptimization) {
200 translateValue(classGen, methodGen);
201 return;
202 }
203
204 // Make name acceptable for use as field name in class
205 String name = Util.escape(getEscapedName());
206
207 // Load reference to the translet (method is in AbstractTranslet)
208 il.append(classGen.loadTranslet());
209
210 // Load the name of the parameter
211 il.append(new PUSH(cpg, name)); // TODO: namespace ?
212 // Generete the value of the parameter (use value in 'select' by def.)
213 translateValue(classGen, methodGen);
214 // Mark this parameter value is not being the default value
215 il.append(new PUSH(cpg, false));
216 // Pass the parameter to the template
217 il.append(new INVOKEVIRTUAL(cpg.addMethodref(TRANSLET_CLASS,
218 ADD_PARAMETER,
219 ADD_PARAMETER_SIG)));
220 il.append(POP); // cleanup stack
221 }
222
223 /**
224 * Release the compiled result tree.
225 */
226 public void releaseResultTree(ClassGenerator classGen, MethodGenerator methodGen) {
227 if (_domAdapter != null) {
228 final ConstantPoolGen cpg = classGen.getConstantPool();
229 final InstructionList il = methodGen.getInstructionList();
230 if (classGen.getStylesheet().callsNodeset() && classGen.getDOMClass().equals(MULTI_DOM_CLASS)) {
231 final int removeDA = cpg.addMethodref(MULTI_DOM_CLASS, "removeDOMAdapter", "(" + DOM_ADAPTER_SIG + ")V");
232 il.append(methodGen.loadDOM());
233 il.append(new CHECKCAST(cpg.addClass(MULTI_DOM_CLASS)));
234 il.append(new ALOAD(_domAdapter.getIndex()));
235 il.append(new CHECKCAST(cpg.addClass(DOM_ADAPTER_CLASS)));
236 il.append(new INVOKEVIRTUAL(removeDA));
237 }
238 final int release = cpg.addInterfaceMethodref(DOM_IMPL_CLASS, "release", "()V");
239 il.append(new ALOAD(_domAdapter.getIndex()));
240 il.append(new INVOKEINTERFACE(release, 1));
241 _domAdapter = null;
242 }
243 }
244 }