Java object pooling and management of own

Mar 31 posted in Java (RSS), comments.

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The concept of object pooling is not wordy here I was, huh, huh. Largely eliminating the need for frequent the same object to create overhead and recovery overhead collector.

No dependencies, JDK 1.5 or later can be used directly, huh, huh

/**
 * @ObjectPool.java
 * @author  Zhang Lei  
 * @since  2010-3-31  Afternoon  01:41:35
 */
package cn.zgl.utils.pool;

import java.util.ArrayList;
import java.util.concurrent.Semaphore;

/**
 * @author  Zhang Lei  
 * @version 2010.03  Object pool management class  
 */
public abstract  class ObjectPool<T> {
         private ArrayList<T> pool = null;
         private int size=0;
         private int step=0;
         private int currentPoolSize=0;
         private Semaphore pass = null;
     /**
      *  Initializes a maxSize ObjectPool  
      * @param maxSize
      */
     public ObjectPool(int maxSize){
 
           // Initialize resource pool  
           this.size =maxSize;
           pool = new ArrayList<T>();
           for(int i=0; i<maxSize; i++){
                pool.add(createT());
           }
           currentPoolSize=maxSize;
           pass = new Semaphore(size);

     }
     /**
      *  Up to initialize a maxSize ObjectPool  , The default initialization initsize than  , After taking the step increment  
      * @param maxSize  The maximum number  
      * @param initsize  Initializes the number     
      * @param step  Increment the number  
      */
     public ObjectPool(int maxSize,int initsize,int step){

         // Initialize resource pool  
         this.size =maxSize;
         this.step=step;
         pool = new ArrayList<T>();
         for(int i=0; i<maxSize; i++){
                 pool.add(createT());
         }
         currentPoolSize=maxSize;
         pass = new Semaphore(size);

     }
     /**
      *  Read one from the pool  
      * @author  Zhang Lei  
      * @since  2010-3-31  Afternoon  04:21:19
      * @return T
      * @return
      * @throws InterruptedException
      */
     public T get() throws InterruptedException{

           // Gets a pass, only get passes to get resource  
           pass.acquire();
           return getSourceFromPool();

     }
     /**
      *  Return a to pool  
      * @author  Zhang Lei  
      * @since  2010-3-31  Afternoon  04:21:30
      * @return void
      * @param resource
      */
     public void put(T resource){

           // The return of the pass, and the return of resources  
           pass.release();
           releaseSourceToPool(resource);

     }
     /**
      *  All releases of the pool  
      * @author  Zhang Lei  
      * @since  2010-3-31  Afternoon  04:21:41
      * @return void
      */
     public void relasePool(){
         for(T t:pool){
                 destroyT(t);
         }
     }
    /**
     *  Read a private  
     * @author  Zhang Lei  
     * @since  2010-3-31  Afternoon  04:22:17
     * @return T
     * @return
     */
    private synchronized T getSourceFromPool() {
        if(pool.size()==0){
           if(currentPoolSize<size){
                  int newT= size-currentPoolSize>step ? step: size-currentPoolSize; 
                  for(int i=0; i<newT; i++){
                  pool.add(createT());
             }
                 currentPoolSize+=newT;
           }
        }
        return pool.remove(0);
     }
     /**
      *  Release one to    Private pool  
      * @author  Zhang Lei  
      * @since  2010-3-31  Afternoon  04:22:34
      * @return void
      * @param resource
      */
     private synchronized void releaseSourceToPool(T resource) {
          // System.out.println("return "+resource);
          pool.add(resource);
     } 
     
     // Destroy the object was created.  
   abstract T createT();
     abstract void destroyT(T t);
     //  Sample  :public class IntegerPool extends ObjectPool<Integer>
}

Here is a simple example, Oh

/**
 * @IntegerPoolExample.java
 * @author  Zhang Lei  
 * @since  2010-3-31  Afternoon  03:18:05
 */
package cn.zgl.utils.pool;

/**
 * @author  Zhang Lei  
 */
public class IntegerPoolExample extends ObjectPool<Integer>{

        /**
         * @param maxSize
         */
        public IntegerPoolExample(int maxSize) {
                super(maxSize);
                // TODO Auto-generated constructor stub
        }
        
        public IntegerPoolExample() {
                super(10);
        }
        /* (non-Javadoc)
         * @see cn.zgl.utils.pool.ObjectPool#createT()
         */
        @Override
        Integer createT() {
                return 0;
        }

        /* (non-Javadoc)
         * @see cn.zgl.utils.pool.ObjectPool#destroyT(java.lang.Object)
         */
        @Override
        void destroyT(Integer t) {
                t=null;
        }
}

Of course, generally do not need to use Integer to manage the pool, and this is just an example, huh, huh.

Use the sample

public static void main(String[] args){
                ObjectPool<Integer> pool= new IntegerPoolExample();
                try{
                        for(int i=0;i<10;i++){
                                // Drawn from the pool a  
                                Integer tmp=pool.get();
                                System.out.println(" The first "+ I +" time output   " +tmp);
                                // Modify the value of this  
                                tmp=i;
                                // The modified value access to this place is just a test test  , In fact the pool object General requirements before using no change after use.  
                                pool.put(tmp);
                        }
                        for(int i=0;i<10;i++){
                                System.out.println(" The first "+ I +" time output   " +pool.get());
                        }
                }catch(InterruptedException e){
                        e.printStackTrace();
                }
                finally{
                        pool.relasePool();
                }

        }

So, stop here. Oh, you lot of pointing, personal information Please do not reproduced