/** * Check that each non static final field has been initialized exactly once, taking into account * the fact that constructors may call other constructors. * * @param cb The ClassBody of the class declaring the fields to check. * @throws SemanticException */ protected void checkNonStaticFinalFieldsInit(ClassBody cb) throws SemanticException { // for each non-static final field instance, check that all // constructors intialize it exactly once, taking into account constructor calls. for (Iterator iter = currCBI.currClassFinalFieldInitCounts.keySet().iterator(); iter.hasNext(); ) { FieldInstance fi = (FieldInstance) iter.next(); if (fi.flags().isFinal() && !fi.flags().isStatic()) { // the field is final and not static // it must be initialized exactly once. // navigate up through all of the the constructors // that this constructor calls. boolean fieldInitializedBeforeConstructors = false; MinMaxInitCount ic = (MinMaxInitCount) currCBI.currClassFinalFieldInitCounts.get(fi); if (ic != null && !InitCount.ZERO.equals(ic.getMin())) { fieldInitializedBeforeConstructors = true; } for (Iterator iter2 = currCBI.allConstructors.iterator(); iter2.hasNext(); ) { ConstructorDecl cd = (ConstructorDecl) iter2.next(); ConstructorInstance ciStart = cd.constructorInstance(); ConstructorInstance ci = ciStart; boolean isInitialized = fieldInitializedBeforeConstructors; while (ci != null) { Set s = (Set) currCBI.fieldsConstructorInitializes.get(ci); if (s != null && s.contains(fi)) { if (isInitialized) { throw new SemanticException( "field \"" + fi.name() + "\" might have already been initialized", cd.position()); } isInitialized = true; } ci = (ConstructorInstance) currCBI.constructorCalls.get(ci); } if (!isInitialized) { throw new SemanticException( "field \"" + fi.name() + "\" might not have been initialized", ciStart.position()); } } } } }
// Declared in AnonymousClasses.jrag at line 52 private AnonymousDecl rewriteRule0() { { setModifiers(new Modifiers(new List().add(new Modifier("final")))); ConstructorDecl constructor = new ConstructorDecl(); addBodyDecl(constructor); constructor.setModifiers((Modifiers) constructorDecl().getModifiers().fullCopy()); String name = "Anonymous" + nextAnonymousIndex(); setID(name); constructor.setID(name); List parameterList = new List(); for (int i = 0; i < constructorDecl().getNumParameter(); i++) { parameterList.add( new ParameterDeclaration( constructorDecl().getParameter(i).type().createBoundAccess(), constructorDecl().getParameter(i).name())); } constructor.setParameterList(parameterList); List argList = new List(); for (int i = 0; i < constructor.getNumParameter(); i++) argList.add(new VarAccess(constructor.getParameter(i).name())); constructor.setConstructorInvocation( new ExprStmt(new SuperConstructorAccess("super", argList))); constructor.setBlock(new Block()); HashSet set = new HashSet(); for (int i = 0; i < getNumBodyDecl(); i++) { if (getBodyDecl(i) instanceof InstanceInitializer) { InstanceInitializer init = (InstanceInitializer) getBodyDecl(i); set.addAll(init.exceptions()); } else if (getBodyDecl(i) instanceof FieldDeclaration) { FieldDeclaration f = (FieldDeclaration) getBodyDecl(i); if (f.isInstanceVariable()) { set.addAll(f.exceptions()); } } } List exceptionList = new List(); for (Iterator iter = set.iterator(); iter.hasNext(); ) { TypeDecl exceptionType = (TypeDecl) iter.next(); if (exceptionType.isNull()) exceptionType = typeNullPointerException(); exceptionList.add(exceptionType.createQualifiedAccess()); } constructor.setExceptionList(exceptionList); return this; } }
/** Perform necessary actions upon seeing the ConstructorDecl <code>cd</code>. */ protected void finishConstructorDecl( FlowGraph graph, ConstructorDecl cd, DataFlowItem dfIn, DataFlowItem dfOut) { ConstructorInstance ci = cd.constructorInstance(); // we need to set currCBI.fieldsConstructorInitializes correctly. // It is meant to contain the non-static final fields that the // constructor ci initializes. // // Note that dfOut.initStatus contains only the MinMaxInitCounts // for _normal_ termination of the constructor (see the // method confluence). This means that if dfOut says the min // count of the initialization for a final non-static field // is one, and that is different from what is recoreded in // currCBI.currClassFinalFieldInitCounts (which is the counts // of the initializations performed by initializers), then // the constructor does indeed initialize the field. Set s = new HashSet(); // go through every final non-static field in dfOut.initStatus Iterator iter = dfOut.initStatus.entrySet().iterator(); while (iter.hasNext()) { Entry e = (Entry) iter.next(); if (e.getKey() instanceof FieldInstance && ((FieldInstance) e.getKey()).flags().isFinal() && !((FieldInstance) e.getKey()).flags().isStatic()) { // we have a final non-static field FieldInstance fi = (FieldInstance) e.getKey(); MinMaxInitCount initCount = (MinMaxInitCount) e.getValue(); MinMaxInitCount origInitCount = (MinMaxInitCount) currCBI.currClassFinalFieldInitCounts.get(fi); if (initCount.getMin() == InitCount.ONE && (origInitCount == null || origInitCount.getMin() == InitCount.ZERO)) { // the constructor initialized this field s.add(fi); } } } if (!s.isEmpty()) { currCBI.fieldsConstructorInitializes.put(ci, s); } }