Copyright (c) 2000, 2013 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
/*******************************************************************************
 * Copyright (c) 2000, 2013 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;

Array access expression AST node type.
ArrayAccess:
   Expression [ Expression ]

Since:
2.0
@noinstantiate
This class is not intended to be instantiated by clients./**
 * Array access expression AST node type.
 *
 * <pre>
 * ArrayAccess:
 *    Expression <b>[</b> Expression <b>]</b>
 * </pre>
 *
 * @since 2.0
 * @noinstantiate This class is not intended to be instantiated by clients.
 */
@SuppressWarnings("rawtypes")
public class ArrayAccess extends Expression {

	
The "array" structural property of this node type (child type: Expression). 
Since:
3.0/**
	 * The "array" structural property of this node type (child type: {@link Expression}).
	 * @since 3.0
	 */
	public static final ChildPropertyDescriptor ARRAY_PROPERTY =
		new ChildPropertyDescriptor(ArrayAccess.class, "array", Expression.class, MANDATORY, CYCLE_RISK); //$NON-NLS-1$

	
The "index" structural property of this node type (child type: Expression). 
Since:
3.0/**
	 * The "index" structural property of this node type (child type: {@link Expression}).
	 * @since 3.0
	 */
	public static final ChildPropertyDescriptor INDEX_PROPERTY =
		new ChildPropertyDescriptor(ArrayAccess.class, "index", Expression.class, MANDATORY, CYCLE_RISK); //$NON-NLS-1$

	
A list of property descriptors (element type: StructuralPropertyDescriptor), or null if uninitialized. /**
	 * 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(ArrayAccess.class, properyList);
		addProperty(ARRAY_PROPERTY, properyList);
		addProperty(INDEX_PROPERTY, properyList);
		PROPERTY_DESCRIPTORS = reapPropertyList(properyList);
	}

	
Returns a list of structural property descriptors for this node type.
Clients must not modify the result.
Params:
apiLevel – the API level; one of the
AST.JLS* constants
Returns:
a list of property descriptors (element type: StructuralPropertyDescriptor)
Since:
3.0/**
	 * 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 array expression; lazily initialized; defaults to an unspecified,
but legal, expression.
/**
	 * The array expression; lazily initialized; defaults to an unspecified,
	 * but legal, expression.
	 */
	private Expression arrayExpression = null;

	
The index expression; lazily initialized; defaults to an unspecified,
but legal, expression.
/**
	 * The index expression; lazily initialized; defaults to an unspecified,
	 * but legal, expression.
	 */
	private Expression indexExpression = null;

	
Creates a new unparented array access expression node owned by the given
AST. By default, the array and index expresssions are unspecified,
but legal.

N.B. This constructor is package-private.

Params:
ast – the AST that is to own this node/**
	 * Creates a new unparented array access expression node owned by the given
	 * AST. By default, the array and index expresssions are unspecified,
	 * but legal.
	 * <p>
	 * N.B. This constructor is package-private.
	 * </p>
	 *
	 * @param ast the AST that is to own this node
	 */
	ArrayAccess(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 == ARRAY_PROPERTY) {
			if (get) {
				return getArray();
			} else {
				setArray((Expression) child);
				return null;
			}
		}
		if (property == INDEX_PROPERTY) {
			if (get) {
				return getIndex();
			} else {
				setIndex((Expression) child);
				return null;
			}
		}
		// allow default implementation to flag the error
		return super.internalGetSetChildProperty(property, get, child);
	}

	@Override
	final int getNodeType0() {
		return ARRAY_ACCESS;
	}

	@Override
	ASTNode clone0(AST target) {
		ArrayAccess result = new ArrayAccess(target);
		result.setSourceRange(getStartPosition(), getLength());
		result.setArray((Expression) getArray().clone(target));
		result.setIndex((Expression) getIndex().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, getArray());
			acceptChild(visitor, getIndex());
		}
		visitor.endVisit(this);
	}

	
Returns the array expression of this array access expression.
Returns:
the array expression node/**
	 * Returns the array expression of this array access expression.
	 *
	 * @return the array expression node
	 */
	public Expression getArray() {
		if (this.arrayExpression == null) {
			// lazy init must be thread-safe for readers
			synchronized (this) {
				if (this.arrayExpression == null) {
					preLazyInit();
					this.arrayExpression = new SimpleName(this.ast);
					postLazyInit(this.arrayExpression, ARRAY_PROPERTY);
				}
			}
		}
		return this.arrayExpression;
	}

	
Sets the array expression of this array access expression.
Params:
expression – the array expression node
Throws:
IllegalArgumentException – if:

the node belongs to a different AST
the node already has a parent
a cycle in would be created
/**
	 * Sets the array expression of this array access expression.
	 *
	 * @param expression the array expression node
	 * @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 setArray(Expression expression) {
		if (expression == null) {
			throw new IllegalArgumentException();
		}
		// an ArrayAccess may occur inside an Expression
		// must check cycles
		ASTNode oldChild = this.arrayExpression;
		preReplaceChild(oldChild, expression, ARRAY_PROPERTY);
		this.arrayExpression = expression;
		postReplaceChild(oldChild, expression, ARRAY_PROPERTY);
	}

	
Returns the index expression of this array access expression.
Returns:
the index expression node/**
	 * Returns the index expression of this array access expression.
	 *
	 * @return the index expression node
	 */
	public Expression getIndex() {
		if (this.indexExpression == null) {
			// lazy init must be thread-safe for readers
			synchronized (this) {
				if (this.indexExpression == null) {
					preLazyInit();
					this.indexExpression = new SimpleName(this.ast);
					postLazyInit(this.indexExpression, INDEX_PROPERTY);
				}
			}
		}
		return this.indexExpression;
	}

	
Sets the index expression of this array access expression.
Params:
expression – the index expression node
Throws:
IllegalArgumentException – if:

the node belongs to a different AST
the node already has a parent
a cycle in would be created
/**
	 * Sets the index expression of this array access expression.
	 *
	 * @param expression the index expression node
	 * @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 setIndex(Expression expression) {
		if (expression == null) {
			throw new IllegalArgumentException();
		}
		// an ArrayAccess may occur inside an Expression
		// must check cycles
		ASTNode oldChild = this.indexExpression;
		preReplaceChild(oldChild, expression, INDEX_PROPERTY);
		this.indexExpression = expression;
		postReplaceChild(oldChild, expression, INDEX_PROPERTY);
	}

	@Override
	int memSize() {
		return BASE_NODE_SIZE + 2 * 4;
	}

	@Override
	int treeSize() {
		return
			memSize()
			+ (this.arrayExpression == null ? 0 : getArray().treeSize())
			+ (this.indexExpression == null ? 0 : getIndex().treeSize());
	}
}