Source Code : Cache LRU

Java Is Open Source Programming Language You Can Download From Java and Java Libraries From http://www.oracle.com. Click Here to download
We provide this code related to title for you to solve your developing problem easily. Libraries which is import in this program you can download from http://www.oracle.com. Click Here or search from google with Libraries Name you get jar file related it

Cache LRU

 
/*
 * Copyright (c) 2009, TamaCat.org
 * All rights reserved.
 */
//package org.tamacat.util;

import java.util.ArrayList;
import java.util.Collection;
import java.util.LinkedHashMap;
import java.util.Set;

public class CacheLRU<K,V> {

  private int maxSize;
  private LinkedHashMap<K, V> cache;
  private ArrayList<K> used;
  
  public CacheLRU(int maxSize) {
    this.maxSize = maxSize;
    this.cache = new LinkedHashMap<K,V>(maxSize);
    this.used = new ArrayList<K>(maxSize);
  }
  
  public CacheLRU() {
    this(10);
  }
  
  public synchronized V get(K key) {
    updateUsed(key);
    return cache.get(key);
  }
  
  public synchronized V put(K key, V value) {
    if (cache.size() >= maxSize && used.size() > 0) {
      cache.remove(used.get(0));
      used.remove(0);
    }
    updateUsed(key);
    return cache.put(key, value);
  }
  
  private void updateUsed(K key) {
    used.remove(key);
    used.add(key);    
  }
  
  public synchronized int size() {
    return cache.size();
  }
  
  public synchronized V remove(K key) {
    used.remove(key);
    return cache.remove(key);
  }
  
  public synchronized void clear() {
    cache.clear();
    used.clear();
  }
  
  public Set<K> keySet() {
    return cache.keySet();
  }
  
  public Collection<V> values() {
    return cache.values();
  }
  
  @Override
  public String toString() {
    return getClass().getName() + "@" + hashCode() + "" + cache.toString();
  }
}

------------

/*
 * Copyright (c) 2009, TamaCat.org
 * All rights reserved.
 */
package org.tamacat.util;

import static org.junit.Assert.*;

import org.junit.After;
import org.junit.Before;
import org.junit.Test;

public class CacheLRUTest {

  @Before
  public void setUp() throws Exception {
  }

  @After
  public void tearDown() throws Exception {
  }

  @Test
  public void testGet() {
    int maxSize = 3;
    CacheLRU<String,String> cache = new CacheLRU<String,String>(maxSize);
    cache.put("1", "1");
    cache.put("2", "2");
    cache.put("3", "3");
    assertEquals(maxSize, cache.size());
    //cache.get("2");
    //cache.get("1");
    //System.out.println(cache.toString());
    cache.put("4", "4");
    cache.put("5", "5");
    //System.out.println(cache.toString());
    assertEquals(maxSize, cache.size());
  }

}

   
  

Thank with us