FileDocCategorySizeDatePackage
ThreadWithAttributes.javaAPI DocGlassfish v2 API4483Fri May 04 22:33:18 BST 2007org.apache.tomcat.util.threads

ThreadWithAttributes.java

/*
 * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS HEADER.
 * 
 * Copyright 1997-2007 Sun Microsystems, Inc. All rights reserved.
 * 
 * Portions Copyright Apache Software Foundation.
 * 
 * The contents of this file are subject to the terms of either the GNU
 * General Public License Version 2 only ("GPL") or the Common Development
 * and Distribution License("CDDL") (collectively, the "License").  You
 * may not use this file except in compliance with the License. You can obtain
 * a copy of the License at https://glassfish.dev.java.net/public/CDDL+GPL.html
 * or glassfish/bootstrap/legal/LICENSE.txt.  See the License for the specific
 * language governing permissions and limitations under the License.
 * 
 * When distributing the software, include this License Header Notice in each
 * file and include the License file at glassfish/bootstrap/legal/LICENSE.txt.
 * Sun designates this particular file as subject to the "Classpath" exception
 * as provided by Sun in the GPL Version 2 section of the License file that
 * accompanied this code.  If applicable, add the following below the License
 * Header, with the fields enclosed by brackets [] replaced by your own
 * identifying information: "Portions Copyrighted [year]
 * [name of copyright owner]"
 * 
 * Contributor(s):
 * 
 * If you wish your version of this file to be governed by only the CDDL or
 * only the GPL Version 2, indicate your decision by adding "[Contributor]
 * elects to include this software in this distribution under the [CDDL or GPL
 * Version 2] license."  If you don't indicate a single choice of license, a
 * recipient has the option to distribute your version of this file under
 * either the CDDL, the GPL Version 2 or to extend the choice of license to
 * its licensees as provided above.  However, if you add GPL Version 2 code
 * and therefore, elected the GPL Version 2 license, then the option applies
 * only if the new code is made subject to such option by the copyright
 * holder.
 */

package org.apache.tomcat.util.threads;

import java.util.Hashtable;

/** Special thread that allows storing of attributes and notes.
 *  A guard is used to prevent untrusted code from accessing the
 *  attributes.
 *
 *  This avoids hash lookups and provide something very similar
 * with ThreadLocal ( but compatible with JDK1.1 and faster on
 * JDK < 1.4 ).
 *
 * The main use is to store 'state' for monitoring ( like "processing
 * request 'GET /' ").
 */
public class ThreadWithAttributes extends Thread {
    
    private Object control;
    public static final int MAX_NOTES=16;
    private Object notes[]=new Object[MAX_NOTES];
    private Hashtable attributes=new Hashtable();
    private String currentStage;
    private Object param;
    
    private Object thData[];

    public ThreadWithAttributes(Object control, Runnable r) {
        super(r);
        this.control=control;
    }
    
    public final Object[] getThreadData(Object control ) {
        return thData;
    }
    
    public final void setThreadData(Object control, Object thData[] ) {
        this.thData=thData;
    }

    /** Notes - for attributes that need fast access ( array )
     * The application is responsible for id management
     */
    public final void setNote( Object control, int id, Object value ) {
        if( this.control != control ) return;
        notes[id]=value;
    }

    /** Information about the curent performed operation
     */
    public final String getCurrentStage(Object control) {
        if( this.control != control ) return null;
        return currentStage;
    }

    /** Information about the current request ( or the main object
     * we are processing )
     */
    public final Object getParam(Object control) {
        if( this.control != control ) return null;
        return param;
    }

    public final void setCurrentStage(Object control, String currentStage) {
        if( this.control != control ) return;
        this.currentStage = currentStage;
    }

    public final void setParam( Object control, Object param ) {
        if( this.control != control ) return;
        this.param=param;
    }

    public final Object getNote(Object control, int id ) {
        if( this.control != control ) return null;
        return notes[id];
    }

    /** Generic attributes. You'll need a hashtable lookup -
     * you can use notes for array access.
     */
    public final Hashtable getAttributes(Object control) {
        return attributes;
    }
}