001 /*
002 $Id: Verifier.java,v 1.41 2005/07/16 20:00:26 phk Exp $
003
004 Copyright 2003 (C) James Strachan and Bob Mcwhirter. All Rights Reserved.
005
006 Redistribution and use of this software and associated documentation
007 ("Software"), with or without modification, are permitted provided
008 that the following conditions are met:
009
010 1. Redistributions of source code must retain copyright
011 statements and notices. Redistributions must also contain a
012 copy of this document.
013
014 2. Redistributions in binary form must reproduce the
015 above copyright notice, this list of conditions and the
016 following disclaimer in the documentation and/or other
017 materials provided with the distribution.
018
019 3. The name "groovy" must not be used to endorse or promote
020 products derived from this Software without prior written
021 permission of The Codehaus. For written permission,
022 please contact info@codehaus.org.
023
024 4. Products derived from this Software may not be called "groovy"
025 nor may "groovy" appear in their names without prior written
026 permission of The Codehaus. "groovy" is a registered
027 trademark of The Codehaus.
028
029 5. Due credit should be given to The Codehaus -
030 http://groovy.codehaus.org/
031
032 THIS SOFTWARE IS PROVIDED BY THE CODEHAUS AND CONTRIBUTORS
033 ``AS IS'' AND ANY EXPRESSED OR IMPLIED WARRANTIES, INCLUDING, BUT
034 NOT LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND
035 FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL
036 THE CODEHAUS OR ITS CONTRIBUTORS BE LIABLE FOR ANY DIRECT,
037 INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES
038 (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR
039 SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
040 HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT,
041 STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE)
042 ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED
043 OF THE POSSIBILITY OF SUCH DAMAGE.
044
045 */
046 package org.codehaus.groovy.classgen;
047
048 import groovy.lang.Closure;
049 import groovy.lang.GString;
050 import groovy.lang.GroovyObject;
051 import groovy.lang.MetaClass;
052
053 import java.lang.reflect.Modifier;
054 import java.util.ArrayList;
055 import java.util.Iterator;
056 import java.util.List;
057
058 import org.codehaus.groovy.ast.ClassNode;
059 import org.codehaus.groovy.ast.CodeVisitorSupport;
060 import org.codehaus.groovy.ast.ConstructorNode;
061 import org.codehaus.groovy.ast.FieldNode;
062 import org.codehaus.groovy.ast.GroovyClassVisitor;
063 import org.codehaus.groovy.ast.InnerClassNode;
064 import org.codehaus.groovy.ast.MethodNode;
065 import org.codehaus.groovy.ast.Parameter;
066 import org.codehaus.groovy.ast.PropertyNode;
067 import org.codehaus.groovy.ast.expr.ArgumentListExpression;
068 import org.codehaus.groovy.ast.expr.BinaryExpression;
069 import org.codehaus.groovy.ast.expr.BooleanExpression;
070 import org.codehaus.groovy.ast.expr.ClosureExpression;
071 import org.codehaus.groovy.ast.expr.ConstantExpression;
072 import org.codehaus.groovy.ast.expr.Expression;
073 import org.codehaus.groovy.ast.expr.FieldExpression;
074 import org.codehaus.groovy.ast.expr.MethodCallExpression;
075 import org.codehaus.groovy.ast.expr.StaticMethodCallExpression;
076 import org.codehaus.groovy.ast.expr.VariableExpression;
077 import org.codehaus.groovy.ast.stmt.BlockStatement;
078 import org.codehaus.groovy.ast.stmt.EmptyStatement;
079 import org.codehaus.groovy.ast.stmt.ExpressionStatement;
080 import org.codehaus.groovy.ast.stmt.IfStatement;
081 import org.codehaus.groovy.ast.stmt.ReturnStatement;
082 import org.codehaus.groovy.ast.stmt.Statement;
083 import org.codehaus.groovy.runtime.ScriptBytecodeAdapter;
084 import org.codehaus.groovy.syntax.Types;
085 import org.codehaus.groovy.syntax.Token;
086 import org.codehaus.groovy.syntax.RuntimeParserException;
087 import org.objectweb.asm.Opcodes;
088
089 /**
090 * Verifies the AST node and adds any defaulted AST code before
091 * bytecode generation occurs.
092 *
093 * @author <a href="mailto:james@coredevelopers.net">James Strachan</a>
094 * @version $Revision: 1.41 $
095 */
096 public class Verifier implements GroovyClassVisitor, Opcodes {
097
098 public static final String __TIMESTAMP = "__timeStamp";
099 private ClassNode classNode;
100 private MethodNode methodNode;
101
102 public ClassNode getClassNode() {
103 return classNode;
104 }
105
106 public MethodNode getMethodNode() {
107 return methodNode;
108 }
109
110 /**
111 * add code to implement GroovyObject
112 * @param node
113 */
114 public void visitClass(ClassNode node) {
115 this.classNode = node;
116
117 if ((classNode.getModifiers() & Opcodes.ACC_INTERFACE) >0) {
118 node.visitContents(this);
119 return;
120 }
121
122 addDefaultParameterMethods(node);
123
124 if (!node.isDerivedFromGroovyObject()) {
125 node.addInterface(GroovyObject.class.getName());
126
127 // lets add a new field for the metaclass
128 StaticMethodCallExpression initMetaClassCall =
129 new StaticMethodCallExpression(
130 ScriptBytecodeAdapter.class.getName(),
131 "getMetaClass",
132 VariableExpression.THIS_EXPRESSION);
133
134 PropertyNode metaClassProperty =
135 node.addProperty("metaClass", ACC_PUBLIC, MetaClass.class.getName(), initMetaClassCall, null, null);
136 metaClassProperty.setSynthetic(true);
137 FieldNode metaClassField = metaClassProperty.getField();
138 metaClassField.setModifiers(metaClassField.getModifiers() | ACC_TRANSIENT);
139
140 FieldExpression metaClassVar = new FieldExpression(metaClassField);
141 IfStatement initMetaClassField =
142 new IfStatement(
143 new BooleanExpression(
144 new BinaryExpression(metaClassVar, Token.newSymbol( Types.COMPARE_EQUAL, -1, -1), ConstantExpression.NULL)),
145 new ExpressionStatement(new BinaryExpression(metaClassVar, Token.newSymbol( Types.EQUAL, -1, -1), initMetaClassCall)),
146 EmptyStatement.INSTANCE);
147
148 node.addSyntheticMethod(
149 "getMetaClass",
150 ACC_PUBLIC,
151 MetaClass.class.getName(),
152 Parameter.EMPTY_ARRAY,
153 new BlockStatement(new Statement[] { initMetaClassField, new ReturnStatement(metaClassVar)}));
154
155 // @todo we should check if the base class implements the invokeMethod method
156
157 // lets add the invokeMethod implementation
158 String superClass = node.getSuperClass();
159 boolean addDelegateObject =
160 (node instanceof InnerClassNode && superClass.equals(Closure.class.getName()))
161 || superClass.equals(GString.class.getName());
162
163 // don't do anything as the base class implements the invokeMethod
164 if (!addDelegateObject) {
165 node.addSyntheticMethod(
166 "invokeMethod",
167 ACC_PUBLIC,
168 Object.class.getName(),
169 new Parameter[] {
170 new Parameter(String.class.getName(), "method"),
171 new Parameter(Object.class.getName(), "arguments")},
172 new BlockStatement(
173 new Statement[] {
174 initMetaClassField,
175 new ReturnStatement(
176 new MethodCallExpression(
177 metaClassVar,
178 "invokeMethod",
179 new ArgumentListExpression(
180 new Expression[] {
181 VariableExpression.THIS_EXPRESSION,
182 new VariableExpression("method"),
183 new VariableExpression("arguments")})))
184 }));
185
186 if (!node.isScript()) {
187 node.addSyntheticMethod(
188 "getProperty",
189 ACC_PUBLIC,
190 Object.class.getName(),
191 new Parameter[] { new Parameter(String.class.getName(), "property")},
192 new BlockStatement(
193 new Statement[] {
194 initMetaClassField,
195 new ReturnStatement(
196 new MethodCallExpression(
197 metaClassVar,
198 "getProperty",
199 new ArgumentListExpression(
200 new Expression[] {
201 VariableExpression.THIS_EXPRESSION,
202 new VariableExpression("property")})))
203 }));
204
205 node.addSyntheticMethod(
206 "setProperty",
207 ACC_PUBLIC,
208 "void",
209 new Parameter[] {
210 new Parameter(String.class.getName(), "property"),
211 new Parameter(Object.class.getName(), "value")},
212 new BlockStatement(
213 new Statement[] {
214 initMetaClassField,
215 new ExpressionStatement(
216 new MethodCallExpression(
217 metaClassVar,
218 "setProperty",
219 new ArgumentListExpression(
220 new Expression[] {
221 VariableExpression.THIS_EXPRESSION,
222 new VariableExpression("property"),
223 new VariableExpression("value")})))
224 }));
225 }
226 }
227 }
228
229 if (node.getDeclaredConstructors().isEmpty()) {
230 ConstructorNode constructor = new ConstructorNode(ACC_PUBLIC, null);
231 constructor.setSynthetic(true);
232 node.addConstructor(constructor);
233 }
234
235 if (!(node instanceof InnerClassNode)) {// add a static timestamp field to the class
236 FieldNode timeTagField = new FieldNode(
237 Verifier.__TIMESTAMP,
238 Modifier.PUBLIC | Modifier.STATIC,
239 "java.lang.Long",
240 //"",
241 node.getName(),
242 new ConstantExpression(new Long(System.currentTimeMillis())));
243 // alternatively , FieldNode timeTagField = SourceUnit.createFieldNode("public static final long __timeStamp = " + System.currentTimeMillis() + "L");
244 timeTagField.setSynthetic(true);
245 node.addField(timeTagField);
246 }
247
248 addFieldInitialization(node);
249
250 node.visitContents(this);
251 }
252 public void visitConstructor(ConstructorNode node) {
253 CodeVisitorSupport checkSuper = new CodeVisitorSupport() {
254 boolean firstMethodCall = true;
255 String type=null;
256 public void visitMethodCallExpression(MethodCallExpression call) {
257 if (!firstMethodCall) return;
258 firstMethodCall = false;
259 String name = call.getMethod();
260 if (!name.equals("super") && !name.equals("this")) return;
261 type=name;
262 call.getArguments().visit(this);
263 type=null;
264 }
265 public void visitVariableExpression(VariableExpression expression) {
266 if (type==null) return;
267 String name = expression.getVariable();
268 if (!name.equals("this") && !name.equals("super")) return;
269 throw new RuntimeParserException("cannot reference "+name+" inside of "+type+"(....) before supertype constructor has been called",expression);
270 }
271 };
272 Statement s = node.getCode();
273 //todo why can a statement can be null?
274 if (s == null) return;
275 s.visit(checkSuper);
276 }
277
278 public void visitMethod(MethodNode node) {
279 this.methodNode = node;
280 Statement statement = node.getCode();
281 if (!node.isVoidMethod()) {
282 if (statement instanceof ExpressionStatement) {
283 ExpressionStatement expStmt = (ExpressionStatement) statement;
284 node.setCode(new ReturnStatement(expStmt.getExpression()));
285 }
286 else if (statement instanceof BlockStatement) {
287 BlockStatement block = (BlockStatement) statement;
288
289 // lets copy the list so we create a new block
290 List list = new ArrayList(block.getStatements());
291 if (!list.isEmpty()) {
292 int idx = list.size() - 1;
293 Statement last = (Statement) list.get(idx);
294 if (last instanceof ExpressionStatement) {
295 ExpressionStatement expStmt = (ExpressionStatement) last;
296 list.set(idx, new ReturnStatement(expStmt.getExpression()));
297 }
298 else if (!(last instanceof ReturnStatement)) {
299 list.add(new ReturnStatement(ConstantExpression.NULL));
300 }
301 }
302 else {
303 list.add(new ReturnStatement(ConstantExpression.NULL));
304 }
305
306 node.setCode(new BlockStatement(filterStatements(list)));
307 }
308 }
309 else if (!node.isAbstract()) {
310 BlockStatement newBlock = new BlockStatement();
311 if (statement instanceof BlockStatement) {
312 newBlock.addStatements(filterStatements(((BlockStatement)statement).getStatements()));
313 }
314 else {
315 newBlock.addStatement(filterStatement(statement));
316 }
317 newBlock.addStatement(ReturnStatement.RETURN_NULL_OR_VOID);
318 node.setCode(newBlock);
319 }
320 if (node.getName().equals("main") && node.isStatic()) {
321 Parameter[] params = node.getParameters();
322 if (params.length == 1) {
323 Parameter param = params[0];
324 if (param.getType() == null || param.getType().equals("java.lang.Object")) {
325 param.setType("java.lang.String[]");
326 }
327 }
328 }
329 statement = node.getCode();
330 if (statement!=null) statement.visit(new VerifierCodeVisitor(this));
331 }
332
333 public void visitField(FieldNode node) {
334 }
335
336 public void visitProperty(PropertyNode node) {
337 String name = node.getName();
338 FieldNode field = node.getField();
339
340
341 String getterPrefix = "get";
342 if ("boolean".equals(node.getType())) {
343 getterPrefix = "is";
344 }
345 String getterName = getterPrefix + capitalize(name);
346 String setterName = "set" + capitalize(name);
347
348 Statement getterBlock = node.getGetterBlock();
349 if (getterBlock == null) {
350 if (!node.isPrivate() && classNode.getGetterMethod(getterName) == null) {
351 getterBlock = createGetterBlock(node, field);
352 }
353 }
354 Statement setterBlock = node.getGetterBlock();
355 if (setterBlock == null) {
356 if (!node.isPrivate() && classNode.getSetterMethod(setterName) == null) {
357 setterBlock = createSetterBlock(node, field);
358 }
359 }
360
361 if (getterBlock != null) {
362 MethodNode getter =
363 new MethodNode(getterName, node.getModifiers(), node.getType(), Parameter.EMPTY_ARRAY, getterBlock);
364 getter.setSynthetic(true);
365 classNode.addMethod(getter);
366 visitMethod(getter);
367
368 if ("java.lang.Boolean".equals(node.getType())) {
369 String secondGetterName = "is" + capitalize(name);
370 MethodNode secondGetter =
371 new MethodNode(secondGetterName, node.getModifiers(), node.getType(), Parameter.EMPTY_ARRAY, getterBlock);
372 secondGetter.setSynthetic(true);
373 classNode.addMethod(secondGetter);
374 visitMethod(secondGetter);
375 }
376 }
377 if (setterBlock != null) {
378 Parameter[] setterParameterTypes = { new Parameter(node.getType(), "value")};
379 MethodNode setter =
380 new MethodNode(setterName, node.getModifiers(), "void", setterParameterTypes, setterBlock);
381 setter.setSynthetic(true);
382 classNode.addMethod(setter);
383 visitMethod(setter);
384 }
385 }
386
387 // Implementation methods
388 //-------------------------------------------------------------------------
389
390 /**
391 * Creates a new helper method for each combination of default parameter expressions
392 */
393 protected void addDefaultParameterMethods(ClassNode node) {
394 List methods = new ArrayList(node.getMethods());
395 for (Iterator iter = methods.iterator(); iter.hasNext();) {
396 MethodNode method = (MethodNode) iter.next();
397 if (method.hasDefaultValue()) {
398 Parameter[] parameters = method.getParameters();
399 int counter = 0;
400 ArrayList paramValues = new ArrayList();
401 int size = parameters.length;
402 for (int i = size - 1; i >= 0; i--) {
403 Parameter parameter = parameters[i];
404 if (parameter != null && parameter.hasDefaultValue()) {
405 paramValues.add(new Integer(i));
406 paramValues.add(parameter.getDefaultValue());
407 counter++;
408 }
409 }
410
411 for (int j = 1; j <= counter; j++) {
412 Parameter[] newParams = new Parameter[parameters.length - j];
413 ArgumentListExpression arguments = new ArgumentListExpression();
414 int index = 0;
415 int k = 1;
416 for (int i = 0; i < parameters.length; i++) {
417 if (k > counter - j && parameters[i] != null && parameters[i].hasDefaultValue()) {
418 arguments.addExpression(parameters[i].getDefaultValue());
419 k++;
420 }
421 else if (parameters[i] != null && parameters[i].hasDefaultValue()) {
422 newParams[index++] = parameters[i];
423 arguments.addExpression(new VariableExpression(parameters[i].getName()));
424 k++;
425 }
426 else {
427 newParams[index++] = parameters[i];
428 arguments.addExpression(new VariableExpression(parameters[i].getName()));
429 }
430 }
431
432 MethodCallExpression expression = new MethodCallExpression(VariableExpression.THIS_EXPRESSION, method.getName(), arguments);
433 Statement code = null;
434 if (method.isVoidMethod()) {
435 code = new ExpressionStatement(expression);
436 }
437 else {
438 code = new ReturnStatement(expression);
439 }
440 node.addMethod(method.getName(), method.getModifiers(), method.getReturnType(), newParams, code);
441 }
442 }
443 }
444 }
445
446 /**
447 * Adds a new method which defaults the values for all the parameters starting
448 * from and including the given index
449 *
450 * @param node the class to add the method
451 * @param method the given method to add a helper of
452 * @param parameters the parameters of the method to add a helper for
453 * @param index the index of the first default value expression parameter to use
454 */
455 protected void addDefaultParameterMethod(ClassNode node, MethodNode method, Parameter[] parameters, int depth, ArrayList values) {
456 // lets create a method using this expression
457 Parameter[] newParams = new Parameter[parameters.length - depth];
458 int index = 0;
459 ArgumentListExpression arguments = new ArgumentListExpression();
460 for (int i = 0; i < parameters.length; i++) {
461 if (parameters[i] != null && parameters[i].hasDefaultValue()) {
462 newParams[index++] = parameters[i];
463 arguments.addExpression(new VariableExpression(parameters[i].getName()));
464 }
465 else {
466 arguments.addExpression(parameters[i].getDefaultValue());
467 }
468 }
469
470 MethodCallExpression expression =
471 new MethodCallExpression(VariableExpression.THIS_EXPRESSION, method.getName(), arguments);
472 Statement code = null;
473 if (method.isVoidMethod()) {
474 code = new ExpressionStatement(expression);
475 }
476 else {
477 code = new ReturnStatement(expression);
478 }
479
480 node.addMethod(method.getName(), method.getModifiers(), method.getReturnType(), newParams, code);
481 }
482
483 /**
484 * Adds a new method which defaults the values for all the parameters starting
485 * from and including the given index
486 *
487 * @param node the class to add the method
488 * @param method the given method to add a helper of
489 * @param parameters the parameters of the method to add a helper for
490 * @param index the index of the first default value expression parameter to use
491 */
492 protected void addDefaultParameterMethod(ClassNode node, MethodNode method, Parameter[] parameters, int index) {
493 // lets create a method using this expression
494 Parameter[] newParams = new Parameter[index];
495 System.arraycopy(parameters, 0, newParams, 0, index);
496
497 ArgumentListExpression arguments = new ArgumentListExpression();
498 int size = parameters.length;
499 for (int i = 0; i < size; i++) {
500 if (i < index) {
501 arguments.addExpression(new VariableExpression(parameters[i].getName()));
502 }
503 else {
504 Expression defaultValue = parameters[i].getDefaultValue();
505 if (defaultValue == null) {
506 throw new RuntimeParserException(
507 "The " + parameters[i].getName() + " parameter must have a default value",
508 method);
509 }
510 else {
511 arguments.addExpression(defaultValue);
512 }
513 }
514 }
515
516 MethodCallExpression expression =
517 new MethodCallExpression(VariableExpression.THIS_EXPRESSION, method.getName(), arguments);
518 Statement code = null;
519 if (method.isVoidMethod()) {
520 code = new ExpressionStatement(expression);
521 }
522 else {
523 code = new ReturnStatement(expression);
524 }
525
526 node.addMethod(method.getName(), method.getModifiers(), method.getReturnType(), newParams, code);
527 }
528
529 protected void addClosureCode(InnerClassNode node) {
530 // add a new invoke
531 }
532
533 protected void addFieldInitialization(ClassNode node) {
534 for (Iterator iter = node.getDeclaredConstructors().iterator(); iter.hasNext();) {
535 addFieldInitialization(node, (ConstructorNode) iter.next());
536 }
537 }
538
539 protected void addFieldInitialization(ClassNode node, ConstructorNode constructorNode) {
540 List statements = new ArrayList();
541 List staticStatements = new ArrayList();
542 for (Iterator iter = node.getFields().iterator(); iter.hasNext();) {
543 addFieldInitialization(statements, staticStatements, constructorNode, (FieldNode) iter.next());
544 }
545 if (!statements.isEmpty()) {
546 Statement code = constructorNode.getCode();
547 List otherStatements = new ArrayList();
548 if (code instanceof BlockStatement) {
549 BlockStatement block = (BlockStatement) code;
550 otherStatements.addAll(block.getStatements());
551 }
552 else if (code != null) {
553 otherStatements.add(code);
554 }
555 if (!otherStatements.isEmpty()) {
556 Statement first = (Statement) otherStatements.get(0);
557 if (isSuperMethodCall(first)) {
558 otherStatements.remove(0);
559 statements.add(0, first);
560 }
561 statements.addAll(otherStatements);
562 }
563 constructorNode.setCode(new BlockStatement(statements));
564 }
565
566 if (!staticStatements.isEmpty()) {
567 node.addStaticInitializerStatements(staticStatements);
568 }
569 }
570
571 protected void addFieldInitialization(
572 List list,
573 List staticList,
574 ConstructorNode constructorNode,
575 FieldNode fieldNode) {
576 Expression expression = fieldNode.getInitialValueExpression();
577 if (expression != null) {
578 ExpressionStatement statement =
579 new ExpressionStatement(
580 new BinaryExpression(
581 new FieldExpression(fieldNode),
582 Token.newSymbol(Types.EQUAL, fieldNode.getLineNumber(), fieldNode.getColumnNumber()),
583 expression));
584 if (fieldNode.isStatic()) {
585 staticList.add(statement);
586 }
587 else {
588 list.add(statement);
589 }
590 }
591 }
592
593 protected boolean isSuperMethodCall(Statement first) {
594 if (first instanceof ExpressionStatement) {
595 ExpressionStatement exprStmt = (ExpressionStatement) first;
596 Expression expr = exprStmt.getExpression();
597 if (expr instanceof MethodCallExpression) {
598 return MethodCallExpression.isSuperMethodCall((MethodCallExpression) expr);
599 }
600 }
601 return false;
602 }
603
604 /**
605 * Capitalizes the start of the given bean property name
606 */
607 public static String capitalize(String name) {
608 return name.substring(0, 1).toUpperCase() + name.substring(1, name.length());
609 }
610
611 protected Statement createGetterBlock(PropertyNode propertyNode, FieldNode field) {
612 Expression expression = new FieldExpression(field);
613 return new ReturnStatement(expression);
614 }
615
616 protected Statement createSetterBlock(PropertyNode propertyNode, FieldNode field) {
617 Expression expression = new FieldExpression(field);
618 return new ExpressionStatement(
619 new BinaryExpression(expression, Token.newSymbol(Types.EQUAL, 0, 0), new VariableExpression("value")));
620 }
621
622 /**
623 * Filters the given statements
624 */
625 protected List filterStatements(List list) {
626 List answer = new ArrayList(list.size());
627 for (Iterator iter = list.iterator(); iter.hasNext();) {
628 answer.add(filterStatement((Statement) iter.next()));
629 }
630 return answer;
631 }
632
633 protected Statement filterStatement(Statement statement) {
634 if (statement instanceof ExpressionStatement) {
635 ExpressionStatement expStmt = (ExpressionStatement) statement;
636 Expression expression = expStmt.getExpression();
637 if (expression instanceof ClosureExpression) {
638 ClosureExpression closureExp = (ClosureExpression) expression;
639 if (!closureExp.isParameterSpecified()) {
640 return closureExp.getCode();
641 }
642 }
643 }
644 return statement;
645 }
646 }