1/*
2 * reserved comment block
3 * DO NOT REMOVE OR ALTER!
4 */
5/*
6 * Licensed to the Apache Software Foundation (ASF) under one or more
7 * contributor license agreements.  See the NOTICE file distributed with
8 * this work for additional information regarding copyright ownership.
9 * The ASF licenses this file to You under the Apache License, Version 2.0
10 * (the "License"); you may not use this file except in compliance with
11 * the License.  You may obtain a copy of the License at
12 *
13 *      http://www.apache.org/licenses/LICENSE-2.0
14 *
15 * Unless required by applicable law or agreed to in writing, software
16 * distributed under the License is distributed on an "AS IS" BASIS,
17 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
18 * See the License for the specific language governing permissions and
19 * limitations under the License.
20 */
21
22package com.sun.org.apache.xalan.internal.xsltc.compiler.util;
23
24import com.sun.org.apache.bcel.internal.generic.ALOAD;
25import com.sun.org.apache.bcel.internal.generic.ASTORE;
26import com.sun.org.apache.bcel.internal.generic.CHECKCAST;
27import com.sun.org.apache.bcel.internal.generic.ConstantPoolGen;
28import com.sun.org.apache.bcel.internal.generic.GETFIELD;
29import com.sun.org.apache.bcel.internal.generic.IFEQ;
30import com.sun.org.apache.bcel.internal.generic.INVOKEINTERFACE;
31import com.sun.org.apache.bcel.internal.generic.INVOKESPECIAL;
32import com.sun.org.apache.bcel.internal.generic.INVOKEVIRTUAL;
33import com.sun.org.apache.bcel.internal.generic.Instruction;
34import com.sun.org.apache.bcel.internal.generic.InstructionList;
35import com.sun.org.apache.bcel.internal.generic.LocalVariableGen;
36import com.sun.org.apache.bcel.internal.generic.NEW;
37import com.sun.org.apache.bcel.internal.generic.PUSH;
38import com.sun.org.apache.xalan.internal.xsltc.compiler.Constants;
39import com.sun.org.apache.xalan.internal.xsltc.compiler.FlowList;
40
41/**
42 * @author Jacek Ambroziak
43 * @author Santiago Pericas-Geertsen
44 * @author Morten Jorgensen
45 */
46public final class ResultTreeType extends Type {
47    private final String _methodName;
48
49    protected ResultTreeType() {
50        _methodName = null;
51    }
52
53    public ResultTreeType(String methodName) {
54        _methodName = methodName;
55    }
56
57    public String toString() {
58        return "result-tree";
59    }
60
61    public boolean identicalTo(Type other) {
62        return (other instanceof ResultTreeType);
63    }
64
65    public String toSignature() {
66        return DOM_INTF_SIG;
67    }
68
69    public com.sun.org.apache.bcel.internal.generic.Type toJCType() {
70        return Util.getJCRefType(toSignature());
71    }
72
73    public String getMethodName() {
74        return _methodName;
75    }
76
77    public boolean implementedAsMethod() {
78        return _methodName != null;
79    }
80
81    /**
82     * Translates a result tree to object of internal type <code>type</code>.
83     * The translation to int is undefined since result trees
84     * are always converted to reals in arithmetic expressions.
85     *
86     * @param classGen A BCEL class generator
87     * @param methodGen A BCEL method generator
88     * @param type An instance of the type to translate the result tree to
89     * @see com.sun.org.apache.xalan.internal.xsltc.compiler.util.Type#translateTo
90     */
91    public void translateTo(ClassGenerator classGen, MethodGenerator methodGen,
92                            Type type) {
93        if (type == Type.String) {
94            translateTo(classGen, methodGen, (StringType)type);
95        }
96        else if (type == Type.Boolean) {
97            translateTo(classGen, methodGen, (BooleanType)type);
98        }
99        else if (type == Type.Real) {
100            translateTo(classGen, methodGen, (RealType)type);
101        }
102        else if (type == Type.NodeSet) {
103            translateTo(classGen, methodGen, (NodeSetType)type);
104        }
105        else if (type == Type.Reference) {
106            translateTo(classGen, methodGen, (ReferenceType)type);
107        }
108        else if (type == Type.Object) {
109            translateTo(classGen, methodGen, (ObjectType) type);
110        }
111        else {
112            ErrorMsg err = new ErrorMsg(ErrorMsg.DATA_CONVERSION_ERR,
113                                        toString(), type.toString());
114            classGen.getParser().reportError(Constants.FATAL, err);
115        }
116    }
117
118    /**
119     * Expects an result tree on the stack and pushes a boolean.
120     * Translates a result tree to a boolean by first converting it to string.
121     *
122     * @param classGen A BCEL class generator
123     * @param methodGen A BCEL method generator
124     * @param type An instance of BooleanType (any)
125     * @see com.sun.org.apache.xalan.internal.xsltc.compiler.util.Type#translateTo
126     */
127    public void translateTo(ClassGenerator classGen, MethodGenerator methodGen,
128                            BooleanType type) {
129        // A result tree is always 'true' when converted to a boolean value,
130        // since the tree always has at least one node (the root).
131        final ConstantPoolGen cpg = classGen.getConstantPool();
132        final InstructionList il = methodGen.getInstructionList();
133        il.append(POP);      // don't need the DOM reference
134        il.append(ICONST_1); // push 'true' on the stack
135    }
136
137    /**
138     * Expects an result tree on the stack and pushes a string.
139     *
140     * @param classGen A BCEL class generator
141     * @param methodGen A BCEL method generator
142     * @param type An instance of StringType (any)
143     * @see com.sun.org.apache.xalan.internal.xsltc.compiler.util.Type#translateTo
144     */
145    public void translateTo(ClassGenerator classGen, MethodGenerator methodGen,
146                            StringType type) {
147        final ConstantPoolGen cpg = classGen.getConstantPool();
148        final InstructionList il = methodGen.getInstructionList();
149
150        if (_methodName == null) {
151            int index = cpg.addInterfaceMethodref(DOM_INTF,
152                                                  "getStringValue",
153                                                  "()"+STRING_SIG);
154            il.append(new INVOKEINTERFACE(index, 1));
155        }
156        else {
157            final String className = classGen.getClassName();
158            final int current = methodGen.getLocalIndex("current");
159
160            // Push required parameters
161            il.append(classGen.loadTranslet());
162            if (classGen.isExternal()) {
163                il.append(new CHECKCAST(cpg.addClass(className)));
164            }
165            il.append(DUP);
166            il.append(new GETFIELD(cpg.addFieldref(className, "_dom",
167                                                   DOM_INTF_SIG)));
168
169            // Create a new instance of a StringValueHandler
170            int index = cpg.addMethodref(STRING_VALUE_HANDLER, "<init>", "()V");
171            il.append(new NEW(cpg.addClass(STRING_VALUE_HANDLER)));
172            il.append(DUP);
173            il.append(DUP);
174            il.append(new INVOKESPECIAL(index));
175
176            // Store new Handler into a local variable
177            final LocalVariableGen handler =
178                methodGen.addLocalVariable("rt_to_string_handler",
179                                           Util.getJCRefType(STRING_VALUE_HANDLER_SIG),
180                                           null, null);
181            handler.setStart(il.append(new ASTORE(handler.getIndex())));
182
183            // Call the method that implements this result tree
184            index = cpg.addMethodref(className, _methodName,
185                                     "("+DOM_INTF_SIG+TRANSLET_OUTPUT_SIG+")V");
186            il.append(new INVOKEVIRTUAL(index));
187
188            // Restore new handler and call getValue()
189            handler.setEnd(il.append(new ALOAD(handler.getIndex())));
190            index = cpg.addMethodref(STRING_VALUE_HANDLER,
191                                     "getValue",
192                                     "()" + STRING_SIG);
193            il.append(new INVOKEVIRTUAL(index));
194        }
195    }
196
197    /**
198     * Expects an result tree on the stack and pushes a real.
199     * Translates a result tree into a real by first converting it to string.
200     *
201     * @param classGen A BCEL class generator
202     * @param methodGen A BCEL method generator
203     * @param type An instance of RealType (any)
204     * @see com.sun.org.apache.xalan.internal.xsltc.compiler.util.Type#translateTo
205     */
206    public void translateTo(ClassGenerator classGen, MethodGenerator methodGen,
207                            RealType type) {
208        translateTo(classGen, methodGen, Type.String);
209        Type.String.translateTo(classGen, methodGen, Type.Real);
210    }
211
212    /**
213     * Expects a result tree on the stack and pushes a boxed result tree.
214     * Result trees are already boxed so the translation is just a NOP.
215     *
216     * @param classGen A BCEL class generator
217     * @param methodGen A BCEL method generator
218     * @param type An instance of ReferenceType (any)
219     * @see com.sun.org.apache.xalan.internal.xsltc.compiler.util.Type#translateTo
220     */
221    public void translateTo(ClassGenerator classGen, MethodGenerator methodGen,
222                            ReferenceType type) {
223        final ConstantPoolGen cpg = classGen.getConstantPool();
224        final InstructionList il = methodGen.getInstructionList();
225
226        if (_methodName == null) {
227            il.append(NOP);
228        }
229        else {
230            LocalVariableGen domBuilder, newDom;
231            final String className = classGen.getClassName();
232            final int current = methodGen.getLocalIndex("current");
233
234            // Push required parameters
235            il.append(classGen.loadTranslet());
236            if (classGen.isExternal()) {
237                il.append(new CHECKCAST(cpg.addClass(className)));
238            }
239            il.append(methodGen.loadDOM());
240
241            // Create new instance of DOM class (with RTF_INITIAL_SIZE nodes)
242            il.append(methodGen.loadDOM());
243            int index = cpg.addInterfaceMethodref(DOM_INTF,
244                                 "getResultTreeFrag",
245                                 "(IZ)" + DOM_INTF_SIG);
246            il.append(new PUSH(cpg, RTF_INITIAL_SIZE));
247            il.append(new PUSH(cpg, false));
248            il.append(new INVOKEINTERFACE(index,3));
249            il.append(DUP);
250
251            // Store new DOM into a local variable
252            newDom = methodGen.addLocalVariable("rt_to_reference_dom",
253                                                Util.getJCRefType(DOM_INTF_SIG),
254                                                null, null);
255            il.append(new CHECKCAST(cpg.addClass(DOM_INTF_SIG)));
256            newDom.setStart(il.append(new ASTORE(newDom.getIndex())));
257
258            // Overwrite old handler with DOM handler
259            index = cpg.addInterfaceMethodref(DOM_INTF,
260                                 "getOutputDomBuilder",
261                                 "()" + TRANSLET_OUTPUT_SIG);
262
263            il.append(new INVOKEINTERFACE(index,1));
264            //index = cpg.addMethodref(DOM_IMPL,
265                //                   "getOutputDomBuilder",
266                //                   "()" + TRANSLET_OUTPUT_SIG);
267            //il.append(new INVOKEVIRTUAL(index));
268            il.append(DUP);
269            il.append(DUP);
270
271            // Store DOM handler in a local in order to call endDocument()
272            domBuilder =
273                methodGen.addLocalVariable("rt_to_reference_handler",
274                                           Util.getJCRefType(TRANSLET_OUTPUT_SIG),
275                                           null, null);
276            domBuilder.setStart(il.append(new ASTORE(domBuilder.getIndex())));
277
278            // Call startDocument on the new handler
279            index = cpg.addInterfaceMethodref(TRANSLET_OUTPUT_INTERFACE,
280                                              "startDocument", "()V");
281            il.append(new INVOKEINTERFACE(index, 1));
282
283            // Call the method that implements this result tree
284            index = cpg.addMethodref(className,
285                                     _methodName,
286                                     "("
287                                     + DOM_INTF_SIG
288                                     + TRANSLET_OUTPUT_SIG
289                                     +")V");
290            il.append(new INVOKEVIRTUAL(index));
291
292            // Call endDocument on the DOM handler
293            domBuilder.setEnd(il.append(new ALOAD(domBuilder.getIndex())));
294            index = cpg.addInterfaceMethodref(TRANSLET_OUTPUT_INTERFACE,
295                                              "endDocument", "()V");
296            il.append(new INVOKEINTERFACE(index, 1));
297
298            // Push the new DOM on the stack
299            newDom.setEnd(il.append(new ALOAD(newDom.getIndex())));
300        }
301    }
302
303    /**
304     * Expects a result tree on the stack and pushes a node-set (iterator).
305     * Note that the produced iterator is an iterator for the DOM that
306     * contains the result tree, and not the DOM that is currently in use.
307     * This conversion here will therefore not directly work with elements
308     * such as <xsl:apply-templates> and <xsl:for-each> without the DOM
309     * parameter/variable being updates as well.
310     *
311     * @param classGen A BCEL class generator
312     * @param methodGen A BCEL method generator
313     * @param type An instance of NodeSetType (any)
314     * @see com.sun.org.apache.xalan.internal.xsltc.compiler.util.Type#translateTo
315     */
316    public void translateTo(ClassGenerator classGen, MethodGenerator methodGen,
317                            NodeSetType type) {
318        final ConstantPoolGen cpg = classGen.getConstantPool();
319        final InstructionList il = methodGen.getInstructionList();
320
321        // Put an extra copy of the result tree (DOM) on the stack
322        il.append(DUP);
323
324        // DOM adapters containing a result tree are not initialised with
325        // translet-type to DOM-type mapping. This must be done now for
326        // XPath expressions and patterns to work for the iterator we create.
327        il.append(classGen.loadTranslet()); // get names array
328        il.append(new GETFIELD(cpg.addFieldref(TRANSLET_CLASS,
329                                               NAMES_INDEX,
330                                               NAMES_INDEX_SIG)));
331        il.append(classGen.loadTranslet()); // get uris array
332        il.append(new GETFIELD(cpg.addFieldref(TRANSLET_CLASS,
333                                               URIS_INDEX,
334                                               URIS_INDEX_SIG)));
335        il.append(classGen.loadTranslet()); // get types array
336        il.append(new GETFIELD(cpg.addFieldref(TRANSLET_CLASS,
337                                               TYPES_INDEX,
338                                               TYPES_INDEX_SIG)));
339        il.append(classGen.loadTranslet()); // get namespaces array
340        il.append(new GETFIELD(cpg.addFieldref(TRANSLET_CLASS,
341                                               NAMESPACE_INDEX,
342                                               NAMESPACE_INDEX_SIG)));
343        // Pass the type mappings to the DOM adapter
344        final int mapping = cpg.addInterfaceMethodref(DOM_INTF,
345                                                      "setupMapping",
346                                                      "(["+STRING_SIG+
347                                                      "["+STRING_SIG+
348                                                      "[I" +
349                                                      "["+STRING_SIG+")V");
350        il.append(new INVOKEINTERFACE(mapping, 5));
351        il.append(DUP);
352
353        // Create an iterator for the root node of the DOM adapter
354        final int iter = cpg.addInterfaceMethodref(DOM_INTF,
355                                                   "getIterator",
356                                                   "()"+NODE_ITERATOR_SIG);
357        il.append(new INVOKEINTERFACE(iter, 1));
358    }
359
360    /**
361     * Subsume result tree into ObjectType.
362     *
363     * @see     com.sun.org.apache.xalan.internal.xsltc.compiler.util.Type#translateTo
364     */
365    public void translateTo(ClassGenerator classGen, MethodGenerator methodGen,
366                            ObjectType type) {
367        methodGen.getInstructionList().append(NOP);
368    }
369
370    /**
371     * Translates a result tree into a non-synthesized boolean.
372     * It does not push a 0 or a 1 but instead returns branchhandle list
373     * to be appended to the false list.
374     *
375     * @param classGen A BCEL class generator
376     * @param methodGen A BCEL method generator
377     * @param type An instance of BooleanType (any)
378     * @see com.sun.org.apache.xalan.internal.xsltc.compiler.util.Type#translateToDesynthesized
379     */
380    public FlowList translateToDesynthesized(ClassGenerator classGen,
381                                             MethodGenerator methodGen,
382                                             BooleanType type) {
383        final InstructionList il = methodGen.getInstructionList();
384        translateTo(classGen, methodGen, Type.Boolean);
385        return new FlowList(il.append(new IFEQ(null)));
386    }
387
388    /**
389     * Translates a result tree to a Java type denoted by <code>clazz</code>.
390     * Expects a result tree on the stack and pushes an object
391     * of the appropriate type after coercion. Result trees are translated
392     * to W3C Node or W3C NodeList and the translation is done
393     * via node-set type.
394     *
395     * @param classGen A BCEL class generator
396     * @param methodGen A BCEL method generator
397     * @param clazz An reference to the Class to translate to
398     * @see com.sun.org.apache.xalan.internal.xsltc.compiler.util.Type#translateTo
399     */
400    public void translateTo(ClassGenerator classGen, MethodGenerator methodGen,
401                            Class clazz) {
402        final String className = clazz.getName();
403        final ConstantPoolGen cpg = classGen.getConstantPool();
404        final InstructionList il = methodGen.getInstructionList();
405
406        if (className.equals("org.w3c.dom.Node")) {
407            translateTo(classGen, methodGen, Type.NodeSet);
408            int index = cpg.addInterfaceMethodref(DOM_INTF,
409                                                  MAKE_NODE,
410                                                  MAKE_NODE_SIG2);
411            il.append(new INVOKEINTERFACE(index, 2));
412        }
413        else if (className.equals("org.w3c.dom.NodeList")) {
414            translateTo(classGen, methodGen, Type.NodeSet);
415            int index = cpg.addInterfaceMethodref(DOM_INTF,
416                                                  MAKE_NODE_LIST,
417                                                  MAKE_NODE_LIST_SIG2);
418            il.append(new INVOKEINTERFACE(index, 2));
419        }
420        else if (className.equals("java.lang.Object")) {
421            il.append(NOP);
422        }
423        else if (className.equals("java.lang.String")) {
424            translateTo(classGen, methodGen, Type.String);
425        }
426        else {
427            ErrorMsg err = new ErrorMsg(ErrorMsg.DATA_CONVERSION_ERR,
428                                        toString(), className);
429            classGen.getParser().reportError(Constants.FATAL, err);
430        }
431    }
432
433    /**
434     * Translates an object of this type to its boxed representation.
435     */
436    public void translateBox(ClassGenerator classGen,
437                             MethodGenerator methodGen) {
438        translateTo(classGen, methodGen, Type.Reference);
439    }
440
441    /**
442     * Translates an object of this type to its unboxed representation.
443     */
444    public void translateUnBox(ClassGenerator classGen,
445                               MethodGenerator methodGen) {
446        methodGen.getInstructionList().append(NOP);
447    }
448
449    /**
450     * Returns the class name of an internal type's external representation.
451     */
452    public String getClassName() {
453        return(DOM_INTF);
454    }
455
456    public Instruction LOAD(int slot) {
457        return new ALOAD(slot);
458    }
459
460    public Instruction STORE(int slot) {
461        return new ASTORE(slot);
462    }
463}
464