Tomcat example source code file (ThreadWithAttributes.java)

This example Tomcat source code file (ThreadWithAttributes.java) is included in the DevDaily.com "Java Source Code Warehouse" project. The intent of this project is to help you "Learn Java by Example" ^TM.

Java - Tomcat tags/keywords

hashtable, hashtable, max_notes=16, object, object, runnable, string, string, thread, threadwithattributes, threadwithattributes, util

The Tomcat ThreadWithAttributes.java source code

/*
 *  Licensed to the Apache Software Foundation (ASF) under one or more
 *  contributor license agreements.  See the NOTICE file distributed with
 *  this work for additional information regarding copyright ownership.
 *  The ASF licenses this file to You under the Apache License, Version 2.0
 *  (the "License"); you may not use this file except in compliance with
 *  the License.  You may obtain a copy of the License at
 *
 *      http://www.apache.org/licenses/LICENSE-2.0
 *
 *  Unless required by applicable law or agreed to in writing, software
 *  distributed under the License is distributed on an "AS IS" BASIS,
 *  WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
 *  See the License for the specific language governing permissions and
 *  limitations under the License.
 */

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 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;
    }
}