| /******************************************************************************* |
| * 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 Eclipse Public License v1.0 |
| * which accompanies this distribution, and is available at |
| * http://www.eclipse.org/legal/epl-v10.html |
| * |
| * Contributors: |
| * IBM Corporation - initial API and implementation |
| *******************************************************************************/ |
| |
| package org.eclipse.jdt.core.dom; |
| |
| import java.util.ArrayList; |
| import java.util.List; |
| |
| /** |
| * Field access expression AST node type. |
| * |
| * <pre> |
| * FieldAccess: |
| * Expression <b>.</b> Identifier |
| * </pre> |
| * |
| * <p> |
| * Note that there are several kinds of expressions that resemble field access |
| * expressions: qualified names, this expressions, and super field access |
| * expressions. The following guidelines help with correct usage: |
| * <ul> |
| * <li>An expression like "foo.this" can only be represented as a this |
| * expression (<code>ThisExpression</code>) containing a simple name. |
| * "this" is a keyword, and therefore invalid as an identifier.</li> |
| * <li>An expression like "this.foo" can only be represented as a field |
| * access expression (<code>FieldAccess</code>) containing a this expression |
| * and a simple name. Again, this is because "this" is a keyword, and |
| * therefore invalid as an identifier.</li> |
| * <li>An expression with "super" can only be represented as a super field |
| * access expression (<code>SuperFieldAccess</code>). "super" is a also |
| * keyword, and therefore invalid as an identifier.</li> |
| * <li>An expression like "foo.bar" can be represented either as a |
| * qualified name (<code>QualifiedName</code>) or as a field access |
| * expression (<code>FieldAccess</code>) containing simple names. Either |
| * is acceptable, and there is no way to choose between them without |
| * information about what the names resolve to |
| * (<code>ASTParser</code> may return either).</li> |
| * <li>Other expressions ending in an identifier, such as "foo().bar" can |
| * only be represented as field access expressions |
| * (<code>FieldAccess</code>).</li> |
| * </ul> |
| * </p> |
| * |
| * @see QualifiedName |
| * @see ThisExpression |
| * @see SuperFieldAccess |
| * @since 2.0 |
| */ |
| public class FieldAccess extends Expression { |
| |
| /** |
| * The "expression" structural property of this node type. |
| * @since 3.0 |
| */ |
| public static final ChildPropertyDescriptor EXPRESSION_PROPERTY = |
| new ChildPropertyDescriptor(FieldAccess.class, "expression", Expression.class, MANDATORY, CYCLE_RISK); //$NON-NLS-1$ |
| |
| /** |
| * The "name" structural property of this node type. |
| * @since 3.0 |
| */ |
| public static final ChildPropertyDescriptor NAME_PROPERTY = |
| new ChildPropertyDescriptor(FieldAccess.class, "name", SimpleName.class, MANDATORY, NO_CYCLE_RISK); //$NON-NLS-1$ |
| |
| /** |
| * A list of property descriptors (element type: |
| * {@link StructuralPropertyDescriptor}), |
| * or null if uninitialized. |
| */ |
| private static final List PROPERTY_DESCRIPTORS; |
| |
| static { |
| List properyList = new ArrayList(3); |
| createPropertyList(FieldAccess.class, properyList); |
| addProperty(EXPRESSION_PROPERTY, properyList); |
| addProperty(NAME_PROPERTY, properyList); |
| PROPERTY_DESCRIPTORS = reapPropertyList(properyList); |
| } |
| |
| /** |
| * Returns a list of structural property descriptors for this node type. |
| * Clients must not modify the result. |
| * |
| * @param apiLevel the API level; one of the |
| * <code>AST.JLS*</code> constants |
| |
| * @return a list of property descriptors (element type: |
| * {@link StructuralPropertyDescriptor}) |
| * @since 3.0 |
| */ |
| public static List propertyDescriptors(int apiLevel) { |
| return PROPERTY_DESCRIPTORS; |
| } |
| |
| /** |
| * The expression; lazily initialized; defaults to an unspecified, |
| * but legal, simple name. |
| */ |
| private Expression expression = null; |
| |
| /** |
| * The field; lazily initialized; defaults to an unspecified, |
| * but legal, simple field name. |
| */ |
| private SimpleName fieldName = null; |
| |
| /** |
| * Creates a new unparented node for a field access expression owned by the |
| * given AST. By default, the expression and field are both unspecified, |
| * but legal, names. |
| * <p> |
| * N.B. This constructor is package-private. |
| * </p> |
| * |
| * @param ast the AST that is to own this node |
| */ |
| FieldAccess(AST ast) { |
| super(ast); |
| } |
| |
| /* (omit javadoc for this method) |
| * Method declared on ASTNode. |
| */ |
| final List internalStructuralPropertiesForType(int apiLevel) { |
| return propertyDescriptors(apiLevel); |
| } |
| |
| /* (omit javadoc for this method) |
| * Method declared on ASTNode. |
| */ |
| final ASTNode internalGetSetChildProperty(ChildPropertyDescriptor property, boolean get, ASTNode child) { |
| if (property == EXPRESSION_PROPERTY) { |
| if (get) { |
| return getExpression(); |
| } else { |
| setExpression((Expression) child); |
| return null; |
| } |
| } |
| if (property == NAME_PROPERTY) { |
| if (get) { |
| return getName(); |
| } else { |
| setName((SimpleName) child); |
| return null; |
| } |
| } |
| // allow default implementation to flag the error |
| return super.internalGetSetChildProperty(property, get, child); |
| } |
| |
| /* (omit javadoc for this method) |
| * Method declared on ASTNode. |
| */ |
| final int getNodeType0() { |
| return FIELD_ACCESS; |
| } |
| |
| /* (omit javadoc for this method) |
| * Method declared on ASTNode. |
| */ |
| ASTNode clone0(AST target) { |
| FieldAccess result = new FieldAccess(target); |
| result.setSourceRange(this.getStartPosition(), this.getLength()); |
| result.setExpression((Expression) getExpression().clone(target)); |
| result.setName((SimpleName) getName().clone(target)); |
| return result; |
| } |
| |
| /* (omit javadoc for this method) |
| * Method declared on ASTNode. |
| */ |
| final boolean subtreeMatch0(ASTMatcher matcher, Object other) { |
| // dispatch to correct overloaded match method |
| return matcher.match(this, other); |
| } |
| |
| /* (omit javadoc for this method) |
| * Method declared on ASTNode. |
| */ |
| void accept0(ASTVisitor visitor) { |
| boolean visitChildren = visitor.visit(this); |
| if (visitChildren) { |
| // visit children in normal left to right reading order |
| acceptChild(visitor, getExpression()); |
| acceptChild(visitor, getName()); |
| } |
| visitor.endVisit(this); |
| } |
| |
| /** |
| * Returns the expression of this field access expression. |
| * |
| * @return the expression node |
| */ |
| public Expression getExpression() { |
| if (this.expression == null) { |
| // lazy init must be thread-safe for readers |
| synchronized (this) { |
| if (this.expression == null) { |
| preLazyInit(); |
| this.expression = new SimpleName(this.ast); |
| postLazyInit(this.expression, EXPRESSION_PROPERTY); |
| } |
| } |
| } |
| return this.expression; |
| } |
| |
| /** |
| * Sets the expression of this field access expression. |
| * |
| * @param expression the new expression |
| * @exception IllegalArgumentException if: |
| * <ul> |
| * <li>the node belongs to a different AST</li> |
| * <li>the node already has a parent</li> |
| * <li>a cycle in would be created</li> |
| * </ul> |
| */ |
| public void setExpression(Expression expression) { |
| if (expression == null) { |
| throw new IllegalArgumentException(); |
| } |
| ASTNode oldChild = this.expression; |
| preReplaceChild(oldChild, expression, EXPRESSION_PROPERTY); |
| this.expression = expression; |
| postReplaceChild(oldChild, expression, EXPRESSION_PROPERTY); |
| } |
| |
| /** |
| * Returns the name of the field accessed in this field access expression. |
| * |
| * @return the field name |
| */ |
| public SimpleName getName() { |
| if (this.fieldName == null) { |
| // lazy init must be thread-safe for readers |
| synchronized (this) { |
| if (this.fieldName == null) { |
| preLazyInit(); |
| this.fieldName = new SimpleName(this.ast); |
| postLazyInit(this.fieldName, NAME_PROPERTY); |
| } |
| } |
| } |
| return this.fieldName; |
| } |
| |
| /** |
| * Sets the name of the field accessed in this field access expression. |
| * |
| * @param fieldName the field name |
| * @exception IllegalArgumentException if: |
| * <ul> |
| * <li>the node belongs to a different AST</li> |
| * <li>the node already has a parent</li> |
| * </ul> |
| */ |
| public void setName(SimpleName fieldName) { |
| if (fieldName == null) { |
| throw new IllegalArgumentException(); |
| } |
| ASTNode oldChild = this.fieldName; |
| preReplaceChild(oldChild, fieldName, NAME_PROPERTY); |
| this.fieldName = fieldName; |
| postReplaceChild(oldChild, fieldName, NAME_PROPERTY); |
| } |
| |
| /* (omit javadoc for this method) |
| * Method declared on ASTNode. |
| */ |
| int memSize() { |
| // treat Code as free |
| return BASE_NODE_SIZE + 2 * 4; |
| } |
| |
| /** |
| * Resolves and returns the binding for the field accessed by this |
| * expression. |
| * <p> |
| * Note that bindings are generally unavailable unless requested when the |
| * AST is being built. |
| * </p> |
| * |
| * @return the variable binding, or <code>null</code> if the binding cannot |
| * be resolved |
| * @since 3.0 |
| */ |
| public IVariableBinding resolveFieldBinding() { |
| return this.ast.getBindingResolver().resolveField(this); |
| } |
| |
| /* (omit javadoc for this method) |
| * Method declared on ASTNode. |
| */ |
| int treeSize() { |
| return |
| memSize() |
| + (this.expression == null ? 0 : getExpression().treeSize()) |
| + (this.fieldName == null ? 0 : getName().treeSize()); |
| } |
| } |
| |