org.eclipse.jdt.core.dom.FieldAccess Maven / Gradle / Ivy
The newest version!
/*******************************************************************************
* Copyright (c) 2000, 2019 IBM Corporation and others.
*
* This program and the accompanying materials
* are made available under the terms of the Eclipse Public License 2.0
* which accompanies this distribution, and is available at
* https://www.eclipse.org/legal/epl-2.0/
*
* SPDX-License-Identifier: EPL-2.0
*
* 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.
*
*
* FieldAccess:
* Expression . Identifier
*
*
*
* 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:
*
*
* - An expression like "foo.this" can only be represented as a this
* expression (
ThisExpression
) containing a simple name.
* "this" is a keyword, and therefore invalid as an identifier.
* - An expression like "this.foo" can only be represented as a field
* access expression (
FieldAccess
) containing a this expression
* and a simple name. Again, this is because "this" is a keyword, and
* therefore invalid as an identifier.
* - An expression with "super" can only be represented as a super field
* access expression (
SuperFieldAccess
). "super" is a also
* keyword, and therefore invalid as an identifier.
* - An expression like "foo.bar" can be represented either as a
* qualified name (
QualifiedName
) or as a field access
* expression (FieldAccess
) containing simple names. Either
* is acceptable, and there is no way to choose between them without
* information about what the names resolve to
* (ASTParser
may return either).
* - Other expressions ending in an identifier, such as "foo().bar" can
* only be represented as field access expressions
* (
FieldAccess
).
*
*
* @see QualifiedName
* @see ThisExpression
* @see SuperFieldAccess
* @since 2.0
* @noinstantiate This class is not intended to be instantiated by clients.
*/
@SuppressWarnings("rawtypes")
public class FieldAccess extends Expression {
/**
* The "expression" structural property of this node type (child type: {@link Expression}).
* @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 (child type: {@link SimpleName}).
* @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
* AST.JLS*
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.
*
* N.B. This constructor is package-private.
*
*
* @param ast the AST that is to own this node
*/
FieldAccess(AST ast) {
super(ast);
}
@Override
final List internalStructuralPropertiesForType(int apiLevel) {
return propertyDescriptors(apiLevel);
}
@Override
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);
}
@Override
final int getNodeType0() {
return FIELD_ACCESS;
}
@Override
ASTNode clone0(AST target) {
FieldAccess result = new FieldAccess(target);
result.setSourceRange(getStartPosition(), getLength());
result.setExpression((Expression) getExpression().clone(target));
result.setName((SimpleName) getName().clone(target));
return result;
}
@Override
final boolean subtreeMatch0(ASTMatcher matcher, Object other) {
// dispatch to correct overloaded match method
return matcher.match(this, other);
}
@Override
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:
*
* - the node belongs to a different AST
* - the node already has a parent
* - a cycle in would be created
*
*/
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:
*
* - the node belongs to a different AST
* - the node already has a parent
*
*/
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);
}
@Override
int memSize() {
// treat Code as free
return BASE_NODE_SIZE + 2 * 4;
}
/**
* Resolves and returns the binding for the field accessed by this
* expression.
*
* Note that bindings are generally unavailable unless requested when the
* AST is being built.
*
*
* @return the variable binding, or null
if the binding cannot
* be resolved
* @since 3.0
*/
public IVariableBinding resolveFieldBinding() {
return this.ast.getBindingResolver().resolveField(this);
}
@Override
int treeSize() {
return
memSize()
+ (this.expression == null ? 0 : getExpression().treeSize())
+ (this.fieldName == null ? 0 : getName().treeSize());
}
}