JavaElementRequestor.java

/*******************************************************************************
 * Copyright (c) 2000, 2009 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.internal.core;

import java.util.ArrayList;

import org.eclipse.jdt.core.IField;
import org.eclipse.jdt.core.IInitializer;
import org.eclipse.jdt.core.IMethod;
import org.eclipse.jdt.core.IPackageFragment;
import org.eclipse.jdt.core.IType;

/**
 * @see IJavaElementRequestor
 */

public class JavaElementRequestor implements IJavaElementRequestor {
	/**
	 * True if this requestor no longer wants to receive results from its
	 * <code>IRequestorNameLookup</code>.
	 */
	protected boolean canceled= false;

	/**
	 * A collection of the resulting fields, or <code>null</code> if no field results have been
	 * received.
	 */
	protected ArrayList fields= null;

	/**
	 * A collection of the resulting initializers, or <code>null</code> if no initializer results
	 * have been received.
	 */
	protected ArrayList initializers= null;

	/**
	 * A collection of the resulting member types, or <code>null</code> if no member type results
	 * have been received.
	 */
	protected ArrayList memberTypes= null;

	/**
	 * A collection of the resulting methods, or <code>null</code> if no method results have been
	 * received.
	 */
	protected ArrayList methods= null;

	/**
	 * A collection of the resulting package fragments, or <code>null</code> if no package fragment
	 * results have been received.
	 */
	protected ArrayList packageFragments= null;

	/**
	 * A collection of the resulting types, or <code>null</code> if no type results have been
	 * received.
	 */
	protected ArrayList types= null;

	/**
	 * Empty arrays used for efficiency
	 */
	protected static final IField[] EMPTY_FIELD_ARRAY= new IField[0];

	protected static final IInitializer[] EMPTY_INITIALIZER_ARRAY= new IInitializer[0];

	protected static final IType[] EMPTY_TYPE_ARRAY= new IType[0];

	protected static final IPackageFragment[] EMPTY_PACKAGE_FRAGMENT_ARRAY= new IPackageFragment[0];

	protected static final IMethod[] EMPTY_METHOD_ARRAY= new IMethod[0];

	/**
	 * @see IJavaElementRequestor
	 */
	public void acceptField(IField field) {
		if (this.fields == null) {
			this.fields= new ArrayList();
		}
		this.fields.add(field);
	}

	/**
	 * @see IJavaElementRequestor
	 */
	public void acceptInitializer(IInitializer initializer) {
		if (this.initializers == null) {
			this.initializers= new ArrayList();
		}
		this.initializers.add(initializer);
	}

	/**
	 * @see IJavaElementRequestor
	 */
	public void acceptMemberType(IType type) {
		if (this.memberTypes == null) {
			this.memberTypes= new ArrayList();
		}
		this.memberTypes.add(type);
	}

	/**
	 * @see IJavaElementRequestor
	 */
	public void acceptMethod(IMethod method) {
		if (this.methods == null) {
			this.methods= new ArrayList();
		}
		this.methods.add(method);
	}

	/**
	 * @see IJavaElementRequestor
	 */
	public void acceptPackageFragment(IPackageFragment packageFragment) {
		if (this.packageFragments == null) {
			this.packageFragments= new ArrayList();
		}
		this.packageFragments.add(packageFragment);
	}

	/**
	 * @see IJavaElementRequestor
	 */
	public void acceptType(IType type) {
		if (this.types == null) {
			this.types= new ArrayList();
		}
		this.types.add(type);
	}

	/**
	 * @see IJavaElementRequestor
	 */
	public IField[] getFields() {
		if (this.fields == null) {
			return EMPTY_FIELD_ARRAY;
		}
		int size= this.fields.size();
		IField[] results= new IField[size];
		this.fields.toArray(results);
		return results;
	}

	/**
	 * @see IJavaElementRequestor
	 */
	public IInitializer[] getInitializers() {
		if (this.initializers == null) {
			return EMPTY_INITIALIZER_ARRAY;
		}
		int size= this.initializers.size();
		IInitializer[] results= new IInitializer[size];
		this.initializers.toArray(results);
		return results;
	}

	/**
	 * @see IJavaElementRequestor
	 */
	public IType[] getMemberTypes() {
		if (this.memberTypes == null) {
			return EMPTY_TYPE_ARRAY;
		}
		int size= this.memberTypes.size();
		IType[] results= new IType[size];
		this.memberTypes.toArray(results);
		return results;
	}

	/**
	 * @see IJavaElementRequestor
	 */
	public IMethod[] getMethods() {
		if (this.methods == null) {
			return EMPTY_METHOD_ARRAY;
		}
		int size= this.methods.size();
		IMethod[] results= new IMethod[size];
		this.methods.toArray(results);
		return results;
	}

	/**
	 * @see IJavaElementRequestor
	 */
	public IPackageFragment[] getPackageFragments() {
		if (this.packageFragments == null) {
			return EMPTY_PACKAGE_FRAGMENT_ARRAY;
		}
		int size= this.packageFragments.size();
		IPackageFragment[] results= new IPackageFragment[size];
		this.packageFragments.toArray(results);
		return results;
	}

	/**
	 * @see IJavaElementRequestor
	 */
	public IType[] getTypes() {
		if (this.types == null) {
			return EMPTY_TYPE_ARRAY;
		}
		int size= this.types.size();
		IType[] results= new IType[size];
		this.types.toArray(results);
		return results;
	}

	/**
	 * @see IJavaElementRequestor
	 */
	public boolean isCanceled() {
		return this.canceled;
	}

	/**
	 * Reset the state of this requestor.
	 */
	public void reset() {
		this.canceled= false;
		this.fields= null;
		this.initializers= null;
		this.memberTypes= null;
		this.methods= null;
		this.packageFragments= null;
		this.types= null;
	}

	/**
	 * Sets the #isCanceled state of this requestor to true or false.
	 */
	public void setCanceled(boolean b) {
		this.canceled= b;
	}
}