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;

While statement AST node type.
WhileStatement:
   while ( Expression ) Statement

Since:
2.0
@noinstantiate
This class is not intended to be instantiated by clients./**
 * While statement AST node type.
 *
 * <pre>
 * WhileStatement:
 *    <b>while</b> <b>(</b> Expression <b>)</b> Statement
 * </pre>
 *
 * @since 2.0
 * @noinstantiate This class is not intended to be instantiated by clients.
 */
@SuppressWarnings("rawtypes")
public class WhileStatement extends Statement {

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

	
The "body" structural property of this node type (child type: Statement). 
Since:
3.0/**
	 * The "body" structural property of this node type (child type: {@link Statement}).
	 * @since 3.0
	 */
	public static final ChildPropertyDescriptor BODY_PROPERTY =
		new ChildPropertyDescriptor(WhileStatement.class, "body", Statement.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 propertyList = new ArrayList(3);
		createPropertyList(WhileStatement.class, propertyList);
		addProperty(EXPRESSION_PROPERTY, propertyList);
		addProperty(BODY_PROPERTY, propertyList);
		PROPERTY_DESCRIPTORS = reapPropertyList(propertyList);
	}

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

	
The body statement; lazily initialized; defaults to an empty block
statement.
/**
	 * The body statement; lazily initialized; defaults to an empty block
	 * statement.
	 */
	private Statement body = null;

	
Creates a new unparented while statement node owned by the given
AST. By default, the expresssion is unspecified, but legal, and
the body statement is an empty block.

N.B. This constructor is package-private.

Params:
ast – the AST that is to own this node/**
	 * Creates a new unparented while statement node owned by the given
	 * AST. By default, the expresssion is unspecified, but legal, and
	 * the body statement is an empty block.
	 * <p>
	 * N.B. This constructor is package-private.
	 * </p>
	 *
	 * @param ast the AST that is to own this node
	 */
	WhileStatement(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 == BODY_PROPERTY) {
			if (get) {
				return getBody();
			} else {
				setBody((Statement) child);
				return null;
			}
		}
		// allow default implementation to flag the error
		return super.internalGetSetChildProperty(property, get, child);
	}

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

	@Override
	ASTNode clone0(AST target) {
		WhileStatement result = new WhileStatement(target);
		result.setSourceRange(getStartPosition(), getLength());
		result.copyLeadingComment(this);
		result.setExpression((Expression) getExpression().clone(target));
		result.setBody((Statement) getBody().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, getBody());
		}
		visitor.endVisit(this);
	}

	
Returns the expression of this while statement.
Returns:
the expression node/**
	 * Returns the expression of this while statement.
	 *
	 * @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 while statement.
Params:
expression – the 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 expression of this while statement.
	 *
	 * @param expression the 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 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 body of this while statement.
Returns:
the body statement node/**
	 * Returns the body of this while statement.
	 *
	 * @return the body statement node
	 */
	public Statement getBody() {
		if (this.body == null) {
			// lazy init must be thread-safe for readers
			synchronized (this) {
				if (this.body == null) {
					preLazyInit();
					this.body = new Block(this.ast);
					postLazyInit(this.body, BODY_PROPERTY);
				}
			}
		}
		return this.body;
	}

	
Sets the body of this while statement.

Special note: The Java language does not allow a local variable declaration
to appear as the body of a while statement (they may only appear within a
block). However, the AST will allow a VariableDeclarationStatement
as the body of a WhileStatement. To get something that will
compile, be sure to embed the VariableDeclarationStatement
inside a Block.

Params:
statement – the body statement 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 body of this while statement.
	 * <p>
	 * Special note: The Java language does not allow a local variable declaration
	 * to appear as the body of a while statement (they may only appear within a
	 * block). However, the AST will allow a <code>VariableDeclarationStatement</code>
	 * as the body of a <code>WhileStatement</code>. To get something that will
	 * compile, be sure to embed the <code>VariableDeclarationStatement</code>
	 * inside a <code>Block</code>.
	 * </p>
	 *
	 * @param statement the body statement 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 setBody(Statement statement) {
		if (statement == null) {
			throw new IllegalArgumentException();
		}
		ASTNode oldChild = this.body;
		preReplaceChild(oldChild, statement, BODY_PROPERTY);
		this.body = statement;
		postReplaceChild(oldChild, statement, BODY_PROPERTY);
	}

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

	@Override
	int treeSize() {
		return
			memSize()
			+ (this.expression == null ? 0 : getExpression().treeSize())
			+ (this.body == null ? 0 : getBody().treeSize());
	}
}