+/*******************************************************************************
+ * Copyright (c) 2000, 2004 IBM Corporation and others.
+ * All rights reserved. This program and the accompanying materials
+ * are made available under the terms of the Common Public License v1.0
+ * which accompanies this distribution, and is available at
+ * http://www.eclipse.org/legal/cpl-v10.html
+ *
+ * Contributors:
+ * IBM Corporation - initial API and implementation
+ *******************************************************************************/
+package org.eclipse.jdt.internal.compiler.ast;
+
+import org.eclipse.jdt.internal.compiler.ASTVisitor;
+import org.eclipse.jdt.internal.compiler.impl.*;
+import org.eclipse.jdt.internal.compiler.classfmt.ClassFileConstants;
+import org.eclipse.jdt.internal.compiler.codegen.*;
+import org.eclipse.jdt.internal.compiler.flow.*;
+import org.eclipse.jdt.internal.compiler.lookup.*;
+
+public class FieldReference extends Reference implements InvocationSite {
+
+ public Expression receiver;
+ public char[] token;
+ public FieldBinding binding, codegenBinding;
+ public long nameSourcePosition; //(start<<32)+end
+ MethodBinding syntheticReadAccessor, syntheticWriteAccessor;
+ public TypeBinding receiverType;
+
+ public FieldReference(char[] source, long pos) {
+
+ token = source;
+ nameSourcePosition = pos;
+ //by default the position are the one of the field (not true for super access)
+ sourceStart = (int) (pos >>> 32);
+ sourceEnd = (int) (pos & 0x00000000FFFFFFFFL);
+ bits |= BindingIds.FIELD;
+
+ }
+
+ public FlowInfo analyseAssignment(
+ BlockScope currentScope,
+ FlowContext flowContext,
+ FlowInfo flowInfo,
+ Assignment assignment,
+ boolean isCompound) {
+
+ // compound assignment extra work
+ if (isCompound) { // check the variable part is initialized if blank final
+ if (binding.isBlankFinal()
+ && receiver.isThis()
+ && currentScope.allowBlankFinalFieldAssignment(binding)
+ && (!flowInfo.isDefinitelyAssigned(binding))) {
+ currentScope.problemReporter().uninitializedBlankFinalField(binding, this);
+ // we could improve error msg here telling "cannot use compound assignment on final blank field"
+ }
+ manageSyntheticReadAccessIfNecessary(currentScope, flowInfo);
+ }
+ flowInfo =
+ receiver
+ .analyseCode(currentScope, flowContext, flowInfo, !binding.isStatic())
+ .unconditionalInits();
+ if (assignment.expression != null) {
+ flowInfo =
+ assignment
+ .expression
+ .analyseCode(currentScope, flowContext, flowInfo)
+ .unconditionalInits();
+ }
+ manageSyntheticWriteAccessIfNecessary(currentScope, flowInfo);
+
+ // check if assigning a final field
+ if (binding.isFinal()) {
+ // in a context where it can be assigned?
+ if (binding.isBlankFinal()
+ && !isCompound
+ && receiver.isThis()
+ && !(receiver instanceof QualifiedThisReference)
+ && ((receiver.bits & ParenthesizedMASK) == 0) // (this).x is forbidden
+ && currentScope.allowBlankFinalFieldAssignment(binding)) {
+ if (flowInfo.isPotentiallyAssigned(binding)) {
+ currentScope.problemReporter().duplicateInitializationOfBlankFinalField(
+ binding,
+ this);
+ } else {
+ flowContext.recordSettingFinal(binding, this, flowInfo);
+ }
+ flowInfo.markAsDefinitelyAssigned(binding);
+ } else {
+ // assigning a final field outside an initializer or constructor or wrong reference
+ currentScope.problemReporter().cannotAssignToFinalField(binding, this);
+ }
+ }
+ return flowInfo;
+ }
+
+ public FlowInfo analyseCode(
+ BlockScope currentScope,
+ FlowContext flowContext,
+ FlowInfo flowInfo) {
+
+ return analyseCode(currentScope, flowContext, flowInfo, true);
+ }
+
+ public FlowInfo analyseCode(
+ BlockScope currentScope,
+ FlowContext flowContext,
+ FlowInfo flowInfo,
+ boolean valueRequired) {
+
+ receiver.analyseCode(currentScope, flowContext, flowInfo, !binding.isStatic());
+ if (valueRequired) {
+ manageSyntheticReadAccessIfNecessary(currentScope, flowInfo);
+ }
+ return flowInfo;
+ }
+
+ public FieldBinding fieldBinding() {
+
+ return binding;
+ }
+
+ public void generateAssignment(
+ BlockScope currentScope,
+ CodeStream codeStream,
+ Assignment assignment,
+ boolean valueRequired) {
+
+ receiver.generateCode(
+ currentScope,
+ codeStream,
+ !this.codegenBinding.isStatic());
+ assignment.expression.generateCode(currentScope, codeStream, true);
+ fieldStore(
+ codeStream,
+ this.codegenBinding,
+ syntheticWriteAccessor,
+ valueRequired);
+ if (valueRequired) {
+ codeStream.generateImplicitConversion(assignment.implicitConversion);
+ }
+ }
+
+ /**
+ * Field reference code generation
+ *
+ * @param currentScope org.eclipse.jdt.internal.compiler.lookup.BlockScope
+ * @param codeStream org.eclipse.jdt.internal.compiler.codegen.CodeStream
+ * @param valueRequired boolean
+ */
+ public void generateCode(
+ BlockScope currentScope,
+ CodeStream codeStream,
+ boolean valueRequired) {
+
+ int pc = codeStream.position;
+ if (constant != NotAConstant) {
+ if (valueRequired) {
+ codeStream.generateConstant(constant, implicitConversion);
+ }
+ } else {
+ boolean isStatic = this.codegenBinding.isStatic();
+ receiver.generateCode(currentScope, codeStream, !isStatic);
+ if (valueRequired) {
+ if (this.codegenBinding.constant == NotAConstant) {
+ if (this.codegenBinding.declaringClass == null) { // array length
+ codeStream.arraylength();
+ } else {
+ if (syntheticReadAccessor == null) {
+ if (isStatic) {
+ codeStream.getstatic(this.codegenBinding);
+ } else {
+ codeStream.getfield(this.codegenBinding);
+ }
+ } else {
+ codeStream.invokestatic(syntheticReadAccessor);
+ }
+ }
+ codeStream.generateImplicitConversion(implicitConversion);
+ } else {
+ if (!isStatic) {
+ codeStream.invokeObjectGetClass(); // perform null check
+ codeStream.pop();
+ }
+ codeStream.generateConstant(this.codegenBinding.constant, implicitConversion);
+ }
+ } else {
+ if (!isStatic){
+ codeStream.invokeObjectGetClass(); // perform null check
+ codeStream.pop();
+ }
+ }
+ }
+ codeStream.recordPositionsFrom(pc, this.sourceStart);
+ }
+
+ public void generateCompoundAssignment(
+ BlockScope currentScope,
+ CodeStream codeStream,
+ Expression expression,
+ int operator,
+ int assignmentImplicitConversion,
+ boolean valueRequired) {
+
+ boolean isStatic;
+ receiver.generateCode(
+ currentScope,
+ codeStream,
+ !(isStatic = this.codegenBinding.isStatic()));
+ if (isStatic) {
+ if (syntheticReadAccessor == null) {
+ codeStream.getstatic(this.codegenBinding);
+ } else {
+ codeStream.invokestatic(syntheticReadAccessor);
+ }
+ } else {
+ codeStream.dup();
+ if (syntheticReadAccessor == null) {
+ codeStream.getfield(this.codegenBinding);
+ } else {
+ codeStream.invokestatic(syntheticReadAccessor);
+ }
+ }
+ int operationTypeID;
+ if ((operationTypeID = implicitConversion >> 4) == T_String) {
+ codeStream.generateStringAppend(currentScope, null, expression);
+ } else {
+ // promote the array reference to the suitable operation type
+ codeStream.generateImplicitConversion(implicitConversion);
+ // generate the increment value (will by itself be promoted to the operation value)
+ if (expression == IntLiteral.One) { // prefix operation
+ codeStream.generateConstant(expression.constant, implicitConversion);
+ } else {
+ expression.generateCode(currentScope, codeStream, true);
+ }
+ // perform the operation
+ codeStream.sendOperator(operator, operationTypeID);
+ // cast the value back to the array reference type
+ codeStream.generateImplicitConversion(assignmentImplicitConversion);
+ }
+ fieldStore(
+ codeStream,
+ this.codegenBinding,
+ syntheticWriteAccessor,
+ valueRequired);
+ }
+
+ public void generatePostIncrement(
+ BlockScope currentScope,
+ CodeStream codeStream,
+ CompoundAssignment postIncrement,
+ boolean valueRequired) {
+
+ boolean isStatic;
+ receiver.generateCode(
+ currentScope,
+ codeStream,
+ !(isStatic = this.codegenBinding.isStatic()));
+ if (isStatic) {
+ if (syntheticReadAccessor == null) {
+ codeStream.getstatic(this.codegenBinding);
+ } else {
+ codeStream.invokestatic(syntheticReadAccessor);
+ }
+ } else {
+ codeStream.dup();
+ if (syntheticReadAccessor == null) {
+ codeStream.getfield(this.codegenBinding);
+ } else {
+ codeStream.invokestatic(syntheticReadAccessor);
+ }
+ }
+ if (valueRequired) {
+ if (isStatic) {
+ if ((this.codegenBinding.type == LongBinding)
+ || (this.codegenBinding.type == DoubleBinding)) {
+ codeStream.dup2();
+ } else {
+ codeStream.dup();
+ }
+ } else { // Stack: [owner][old field value] ---> [old field value][owner][old field value]
+ if ((this.codegenBinding.type == LongBinding)
+ || (this.codegenBinding.type == DoubleBinding)) {
+ codeStream.dup2_x1();
+ } else {
+ codeStream.dup_x1();
+ }
+ }
+ }
+ codeStream.generateConstant(
+ postIncrement.expression.constant,
+ implicitConversion);
+ codeStream.sendOperator(postIncrement.operator, this.codegenBinding.type.id);
+ codeStream.generateImplicitConversion(
+ postIncrement.assignmentImplicitConversion);
+ fieldStore(codeStream, this.codegenBinding, syntheticWriteAccessor, false);
+ }
+
+ public static final Constant getConstantFor(
+ FieldBinding binding,
+ Reference reference,
+ boolean isImplicit,
+ Scope referenceScope) {
+
+ //propagation of the constant.
+
+ //ref can be a FieldReference, a SingleNameReference or a QualifiedNameReference
+ //indexInQualification may have a value greater than zero only for QualifiednameReference
+ //if ref==null then indexInQualification==0 AND implicitReceiver == false. This case is a
+ //degenerated case where a fake reference field (null)
+ //is associted to a real FieldBinding in order
+ //to allow its constant computation using the regular path (in other words, find the fieldDeclaration
+ //and proceed to its type resolution). As implicitReceiver is false, no error reporting
+ //against ref will be used ==> no nullPointerException risk ....
+
+ //special treatment for langage-built-in field (their declaring class is null)
+ if (binding.declaringClass == null) {
+ //currently only one field "length" : the constant computation is never done
+ return NotAConstant;
+ }
+ if (!binding.isFinal()) {
+ return binding.constant = NotAConstant;
+ }
+ if (binding.constant != null) {
+ if (isImplicit || (reference instanceof QualifiedNameReference
+ && binding == ((QualifiedNameReference)reference).binding)) {
+ return binding.constant;
+ }
+ return NotAConstant;
+ }
+
+ //The field has not been yet type checked.
+ //It also means that the field is not coming from a class that
+ //has already been compiled. It can only be from a class within
+ //compilation units to process. Thus the field is NOT from a BinaryTypeBinbing
+
+ SourceTypeBinding typeBinding = (SourceTypeBinding) binding.declaringClass;
+ TypeDeclaration typeDecl = typeBinding.scope.referenceContext;
+ FieldDeclaration fieldDecl = typeDecl.declarationOf(binding);
+
+ fieldDecl.resolve(binding.isStatic() //side effect on binding
+ ? typeDecl.staticInitializerScope
+ : typeDecl.initializerScope);
+
+ if (isImplicit || (reference instanceof QualifiedNameReference
+ && binding == ((QualifiedNameReference)reference).binding)) {
+ return binding.constant;
+ }
+ return NotAConstant;
+ }
+
+ public boolean isSuperAccess() {
+
+ return receiver.isSuper();
+ }
+
+ public boolean isTypeAccess() {
+
+ return receiver != null && receiver.isTypeReference();
+ }
+
+ /*
+ * No need to emulate access to protected fields since not implicitly accessed
+ */
+ public void manageSyntheticReadAccessIfNecessary(BlockScope currentScope, FlowInfo flowInfo) {
+
+ if (!flowInfo.isReachable()) return;
+ if (binding.isPrivate()) {
+ if ((currentScope.enclosingSourceType() != binding.declaringClass)
+ && (binding.constant == NotAConstant)) {
+ syntheticReadAccessor =
+ ((SourceTypeBinding) binding.declaringClass).addSyntheticMethod(binding, true);
+ currentScope.problemReporter().needToEmulateFieldReadAccess(binding, this);
+ return;
+ }
+
+ } else if (receiver instanceof QualifiedSuperReference) { // qualified super
+
+ // qualified super need emulation always
+ SourceTypeBinding destinationType =
+ (SourceTypeBinding) (((QualifiedSuperReference) receiver)
+ .currentCompatibleType);
+ syntheticReadAccessor = destinationType.addSyntheticMethod(binding, true);
+ currentScope.problemReporter().needToEmulateFieldReadAccess(binding, this);
+ return;
+
+ } else if (binding.isProtected()) {
+
+ SourceTypeBinding enclosingSourceType;
+ if (((bits & DepthMASK) != 0)
+ && binding.declaringClass.getPackage()
+ != (enclosingSourceType = currentScope.enclosingSourceType()).getPackage()) {
+
+ SourceTypeBinding currentCompatibleType =
+ (SourceTypeBinding) enclosingSourceType.enclosingTypeAt(
+ (bits & DepthMASK) >> DepthSHIFT);
+ syntheticReadAccessor = currentCompatibleType.addSyntheticMethod(binding, true);
+ currentScope.problemReporter().needToEmulateFieldReadAccess(binding, this);
+ return;
+ }
+ }
+ // if the binding declaring class is not visible, need special action
+ // for runtime compatibility on 1.2 VMs : change the declaring class of the binding
+ // NOTE: from target 1.2 on, field's declaring class is touched if any different from receiver type
+ if (binding.declaringClass != this.receiverType
+ && !this.receiverType.isArrayType()
+ && binding.declaringClass != null // array.length
+ && binding.constant == NotAConstant
+ && ((currentScope.environment().options.targetJDK >= ClassFileConstants.JDK1_2
+ && binding.declaringClass.id != T_Object)
+ //no change for Object fields (in case there was)
+ || !binding.declaringClass.canBeSeenBy(currentScope))) {
+ this.codegenBinding =
+ currentScope.enclosingSourceType().getUpdatedFieldBinding(
+ binding,
+ (ReferenceBinding) this.receiverType);
+ }
+ }
+
+ /*
+ * No need to emulate access to protected fields since not implicitly accessed
+ */
+ public void manageSyntheticWriteAccessIfNecessary(BlockScope currentScope, FlowInfo flowInfo) {
+
+ if (!flowInfo.isReachable()) return;
+ if (binding.isPrivate()) {
+ if (currentScope.enclosingSourceType() != binding.declaringClass) {
+ syntheticWriteAccessor =
+ ((SourceTypeBinding) binding.declaringClass).addSyntheticMethod(binding, false);
+ currentScope.problemReporter().needToEmulateFieldWriteAccess(binding, this);
+ return;
+ }
+
+ } else if (receiver instanceof QualifiedSuperReference) { // qualified super
+
+ // qualified super need emulation always
+ SourceTypeBinding destinationType =
+ (SourceTypeBinding) (((QualifiedSuperReference) receiver)
+ .currentCompatibleType);
+ syntheticWriteAccessor = destinationType.addSyntheticMethod(binding, false);
+ currentScope.problemReporter().needToEmulateFieldWriteAccess(binding, this);
+ return;
+
+ } else if (binding.isProtected()) {
+
+ SourceTypeBinding enclosingSourceType;
+ if (((bits & DepthMASK) != 0)
+ && binding.declaringClass.getPackage()
+ != (enclosingSourceType = currentScope.enclosingSourceType()).getPackage()) {
+
+ SourceTypeBinding currentCompatibleType =
+ (SourceTypeBinding) enclosingSourceType.enclosingTypeAt(
+ (bits & DepthMASK) >> DepthSHIFT);
+ syntheticWriteAccessor =
+ currentCompatibleType.addSyntheticMethod(binding, false);
+ currentScope.problemReporter().needToEmulateFieldWriteAccess(binding, this);
+ return;
+ }
+ }
+ // if the binding declaring class is not visible, need special action
+ // for runtime compatibility on 1.2 VMs : change the declaring class of the binding
+ // NOTE: from target 1.2 on, field's declaring class is touched if any different from receiver type
+ if (binding.declaringClass != this.receiverType
+ && !this.receiverType.isArrayType()
+ && binding.declaringClass != null // array.length
+ && binding.constant == NotAConstant
+ && ((currentScope.environment().options.targetJDK >= ClassFileConstants.JDK1_2
+ && binding.declaringClass.id != T_Object)
+ //no change for Object fields (in case there was)
+ || !binding.declaringClass.canBeSeenBy(currentScope))) {
+ this.codegenBinding =
+ currentScope.enclosingSourceType().getUpdatedFieldBinding(
+ binding,
+ (ReferenceBinding) this.receiverType);
+ }
+ }
+
+ public StringBuffer printExpression(int indent, StringBuffer output) {
+
+ return receiver.printExpression(0, output).append('.').append(token);
+ }
+
+ public TypeBinding resolveType(BlockScope scope) {
+
+ // Answer the signature type of the field.
+ // constants are propaged when the field is final
+ // and initialized with a (compile time) constant
+
+ //always ignore receiver cast, since may affect constant pool reference
+ boolean receiverCast = false;
+ if (this.receiver instanceof CastExpression) {
+ this.receiver.bits |= IgnoreNeedForCastCheckMASK; // will check later on
+ receiverCast = true;
+ }
+ this.receiverType = receiver.resolveType(scope);
+ if (this.receiverType == null) {
+ constant = NotAConstant;
+ return null;
+ }
+ if (receiverCast) {
+ // due to change of declaring class with receiver type, only identity cast should be notified
+ if (((CastExpression)this.receiver).expression.resolvedType == this.receiverType) {
+ scope.problemReporter().unnecessaryCast((CastExpression)this.receiver);
+ }
+ }
+ // the case receiverType.isArrayType and token = 'length' is handled by the scope API
+ this.codegenBinding = this.binding = scope.getField(this.receiverType, token, this);
+ if (!binding.isValidBinding()) {
+ constant = NotAConstant;
+ scope.problemReporter().invalidField(this, this.receiverType);
+ return null;
+ }
+
+ if (isFieldUseDeprecated(binding, scope, (this.bits & IsStrictlyAssignedMASK) !=0)) {
+ scope.problemReporter().deprecatedField(binding, this);
+ }
+ boolean isImplicitThisRcv = receiver.isImplicitThis();
+ constant = FieldReference.getConstantFor(binding, this, isImplicitThisRcv, scope);
+ if (!isImplicitThisRcv) {
+ constant = NotAConstant;
+ }
+ if (binding.isStatic()) {
+ // static field accessed through receiver? legal but unoptimal (optional warning)
+ if (!(isImplicitThisRcv
+ || receiver.isSuper()
+ || (receiver instanceof NameReference
+ && (((NameReference) receiver).bits & BindingIds.TYPE) != 0))) {
+ scope.problemReporter().nonStaticAccessToStaticField(this, binding);
+ }
+ if (!isImplicitThisRcv && binding.declaringClass != receiverType) {
+ scope.problemReporter().indirectAccessToStaticField(this, binding);
+ }
+ }
+ return this.resolvedType = binding.type;
+ }
+
+ public void setActualReceiverType(ReferenceBinding receiverType) {
+ // ignored
+ }
+
+ public void setDepth(int depth) {
+
+ bits &= ~DepthMASK; // flush previous depth if any
+ if (depth > 0) {
+ bits |= (depth & 0xFF) << DepthSHIFT; // encoded on 8 bits
+ }
+ }
+
+ public void setFieldIndex(int index) {
+ // ignored
+ }
+
+ public void traverse(ASTVisitor visitor, BlockScope scope) {
+
+ if (visitor.visit(this, scope)) {
+ receiver.traverse(visitor, scope);
+ }
+ visitor.endVisit(this, scope);
+ }
+}