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.HashMap;
import java.util.List;
import java.util.Map;

Prefix expression AST node type.
PrefixExpression:
   PrefixOperator Expression

Since:
2.0
@noinstantiate
This class is not intended to be instantiated by clients./**
 * Prefix expression AST node type.
 *
 * <pre>
 * PrefixExpression:
 *    PrefixOperator Expression
 * </pre>
 *
 * @since 2.0
 * @noinstantiate This class is not intended to be instantiated by clients.
 */
@SuppressWarnings({"rawtypes", "unchecked"})
public class PrefixExpression extends Expression {

	
Prefix operators (typesafe enumeration).
PrefixOperator:
   ++  INCREMENT
   --  DECREMENT
   +  PLUS
   -  MINUS
   ~  COMPLEMENT
   !  NOT

/**
 	 * Prefix operators (typesafe enumeration).
	 * <pre>
	 * PrefixOperator:
	 *    <b><code>++</code></b>  <code>INCREMENT</code>
	 *    <b><code>--</code></b>  <code>DECREMENT</code>
	 *    <b><code>+</code></b>  <code>PLUS</code>
	 *    <b><code>-</code></b>  <code>MINUS</code>
	 *    <b><code>~</code></b>  <code>COMPLEMENT</code>
	 *    <b><code>!</code></b>  <code>NOT</code>
	 * </pre>
	 */
	public static class Operator {

		
The token for the operator.
/**
		 * The token for the operator.
		 */
		private String token;

		
Creates a new prefix operator with the given token.

Note: this constructor is private. The only instances
ever created are the ones for the standard operators.

Params:
token – the character sequence for the operator/**
		 * Creates a new prefix operator with the given token.
		 * <p>
		 * Note: this constructor is private. The only instances
		 * ever created are the ones for the standard operators.
		 * </p>
		 *
		 * @param token the character sequence for the operator
		 */
		private Operator(String token) {
			this.token = token;
		}

		
Returns the character sequence for the operator.
Returns:
the character sequence for the operator/**
		 * Returns the character sequence for the operator.
		 *
		 * @return the character sequence for the operator
		 */
		@Override
		public String toString() {
			return this.token;
		}

		
Prefix increment "++" operator. /** Prefix increment "++" operator. */
		public static final Operator INCREMENT = new Operator("++");//$NON-NLS-1$
		
Prefix decrement "--" operator. /** Prefix decrement "--" operator. */
		public static final Operator DECREMENT = new Operator("--");//$NON-NLS-1$
		
Unary plus "+" operator. /** Unary plus "+" operator. */
		public static final Operator PLUS = new Operator("+");//$NON-NLS-1$
		
Unary minus "-" operator. /** Unary minus "-" operator. */
		public static final Operator MINUS = new Operator("-");//$NON-NLS-1$
		
Bitwise complement "~" operator. /** Bitwise complement "~" operator. */
		public static final Operator COMPLEMENT = new Operator("~");//$NON-NLS-1$
		
Logical complement "!" operator. /** Logical complement "!" operator. */
		public static final Operator NOT = new Operator("!");//$NON-NLS-1$

		
Map from token to operator (key type: String;
value type: Operator).
/**
		 * Map from token to operator (key type: <code>String</code>;
		 * value type: <code>Operator</code>).
		 */
		private static final Map CODES;
		static {
			CODES = new HashMap(20);
			Operator[] ops = {
					INCREMENT,
					DECREMENT,
					PLUS,
					MINUS,
					COMPLEMENT,
					NOT,
				};
			for (int i = 0; i < ops.length; i++) {
				CODES.put(ops[i].toString(), ops[i]);
			}
		}

		
Returns the prefix operator corresponding to the given string,
or null if none.

toOperator is the converse of toString:
that is, Operator.toOperator(op.toString()) == op for
all operators op.

Params:
token – the character sequence for the operator
Returns:
the prefix operator, or null if none/**
		 * Returns the prefix operator corresponding to the given string,
		 * or <code>null</code> if none.
		 * <p>
		 * <code>toOperator</code> is the converse of <code>toString</code>:
		 * that is, <code>Operator.toOperator(op.toString()) == op</code> for
		 * all operators <code>op</code>.
		 * </p>
		 *
		 * @param token the character sequence for the operator
		 * @return the prefix operator, or <code>null</code> if none
		 */
		public static Operator toOperator(String token) {
			return (Operator) CODES.get(token);
		}
	}

	
The "operator" structural property of this node type (type: Operator). 
Since:
3.0/**
	 * The "operator" structural property of this node type (type: {@link PrefixExpression.Operator}).
	 * @since 3.0
	 */
	public static final SimplePropertyDescriptor OPERATOR_PROPERTY =
		new SimplePropertyDescriptor(PrefixExpression.class, "operator", PrefixExpression.Operator.class, MANDATORY); //$NON-NLS-1$

	
The "operand" structural property of this node type (child type: Expression). 
Since:
3.0/**
	 * The "operand" structural property of this node type (child type: {@link Expression}).
	 * @since 3.0
	 */
	public static final ChildPropertyDescriptor OPERAND_PROPERTY =
		new ChildPropertyDescriptor(PrefixExpression.class, "operand", 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 propertyList = new ArrayList(3);
		createPropertyList(PrefixExpression.class, propertyList);
		addProperty(OPERATOR_PROPERTY, propertyList);
		addProperty(OPERAND_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 operator; defaults to an unspecified prefix operator.
/**
	 * The operator; defaults to an unspecified prefix operator.
	 */
	private PrefixExpression.Operator operator =
		PrefixExpression.Operator.PLUS;

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

	
Creates a new AST node for an prefix expression owned by the given
AST. By default, the node has unspecified (but legal) operator and
operand.
Params:
ast – the AST that is to own this node/**
	 * Creates a new AST node for an prefix expression owned by the given
	 * AST. By default, the node has unspecified (but legal) operator and
	 * operand.
	 *
	 * @param ast the AST that is to own this node
	 */
	PrefixExpression(AST ast) {
		super(ast);
	}

	@Override
	final List internalStructuralPropertiesForType(int apiLevel) {
		return propertyDescriptors(apiLevel);
	}

	@Override
	final Object internalGetSetObjectProperty(SimplePropertyDescriptor property, boolean get, Object value) {
		if (property == OPERATOR_PROPERTY) {
			if (get) {
				return getOperator();
			} else {
				setOperator((Operator) value);
				return null;
			}
		}
		// allow default implementation to flag the error
		return super.internalGetSetObjectProperty(property, get, value);
	}

	@Override
	final ASTNode internalGetSetChildProperty(ChildPropertyDescriptor property, boolean get, ASTNode child) {
		if (property == OPERAND_PROPERTY) {
			if (get) {
				return getOperand();
			} else {
				setOperand((Expression) child);
				return null;
			}
		}
		// allow default implementation to flag the error
		return super.internalGetSetChildProperty(property, get, child);
	}

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

	@Override
	ASTNode clone0(AST target) {
		PrefixExpression result = new PrefixExpression(target);
		result.setSourceRange(getStartPosition(), getLength());
		result.setOperator(getOperator());
		result.setOperand((Expression) getOperand().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, getOperand());
		}
		visitor.endVisit(this);
	}

	
Returns the operator of this prefix expression.
Returns:
the operator/**
	 * Returns the operator of this prefix expression.
	 *
	 * @return the operator
	 */
	public PrefixExpression.Operator getOperator() {
		return this.operator;
	}

	
Sets the operator of this prefix expression.
Params:
operator – the operator
Throws:
IllegalArgumentException – if the argument is incorrect/**
	 * Sets the operator of this prefix expression.
	 *
	 * @param operator the operator
	 * @exception IllegalArgumentException if the argument is incorrect
	 */
	public void setOperator(PrefixExpression.Operator operator) {
		if (operator == null) {
			throw new IllegalArgumentException();
		}
		preValueChange(OPERATOR_PROPERTY);
		this.operator = operator;
		postValueChange(OPERATOR_PROPERTY);
	}

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

	
Sets the operand of this prefix expression.
Params:
expression – the operand 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 operand of this prefix expression.
	 *
	 * @param expression the operand 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 setOperand(Expression expression) {
		if (expression == null) {
			throw new IllegalArgumentException();
		}
		ASTNode oldChild = this.operand;
		preReplaceChild(oldChild, expression, OPERAND_PROPERTY);
		this.operand = expression;
		postReplaceChild(oldChild, expression, OPERAND_PROPERTY);
	}

	@Override
	int memSize() {
		// treat Operator as free
		return BASE_NODE_SIZE + 2 * 4;
	}

	@Override
	int treeSize() {
		return
			memSize()
			+ (this.operand == null ? 0 : getOperand().treeSize());
	}
}