05、MemCached快速入门：Java缓存技术Memcached实例-程序员快看-教程，程序员编程资料站

1下载memcached-1.2.1-win32.zip 并且解压.

2新建web project项目名字自己取,然后导入必要的包,alisoft-xplatform-asf-cache-2.5.1.jar,commons-logging-1.0.3.jar,log4j-1.2.13.jar

3新建类 user.java

package bean;

import java.io.Serializable;

public class User implements Serializable{

private static final long serialVersionUID = -3896605600471191953L;
private int uid;
private String uname;
private String upass;

public int getUid() {
return uid;
}
public void setUid(int uid) {
this.uid = uid;
}
public String getUname() {
return uname;
}
public void setUname(String uname) {
this.uname = uname;
}
public String getUpass() {
return upass;
}
public void setUpass(String upass) {
this.upass = upass;
}

}

4新建 JdbcConnector.java

package util;

import java.sql.Connection;
import java.sql.DriverManager;
import java.sql.SQLException;

public class JdbcConnector {
//定义数据库连接常量
private final static String DRIVER = "com.mysql.jdbc.Driver";
private final static String URL = "jdbc:mysql://192.168.1.13:3306/test";
private final static String DBNAME = "root";
private final static String DBPASS = "123456";

public Connection getConn()throws ClassNotFoundException,SQLException {
//加载驱动
Class.forName(DRIVER);
//通过DriverManager对象得到连接
Connection conn = DriverManager.getConnection(URL,DBNAME,DBPASS);
//返回数据库连接
return conn;
}
}

5新建 UserDao.java

package util;

import java.sql.SQLException;
import java.util.ArrayList;
import java.util.List;

import bean.User;

import com.mysql.jdbc.Connection;
import com.mysql.jdbc.PreparedStatement;
import com.mysql.jdbc.ResultSet;

public class UserDao extends JdbcConnector {
//定义全局变量
Connection conn = null;
PreparedStatement pstmt = null;
ResultSet rs = null;

public User getUserById(int uid) {
//创建User对象
User user = null;
//创建SQL语句
String sql = "select * from user where uid=?";

try{
//获得数据库连接
conn = (Connection) this.getConn();
//通过Connection对象创建PrepareStatement对象
pstmt = (PreparedStatement) conn.prepareStatement(sql);
//设置SQL语句的参数
pstmt.setInt(2, uid);
//执行查询，将查询结果赋给ResultSet对象
rs= (ResultSet) pstmt.executeQuery();
//遍历指针
while (rs.next())
{
user = new User();
user.setUid(rs.getInt("uid"));
user.setUname(rs.getString("uname"));
user.setUpass(rs.getString("upass"));
}
}catch (ClassNotFoundException e) {
e.printStackTrace();
}catch (SQLException e) {
e.printStackTrace();
}
return user;
}

@SuppressWarnings("unchecked")
public List getUserList() {
//创建ArrayList对象
List userList = new ArrayList();

//创建SQL对象
String sql = "select * from user";

try{
conn = (Connection) this.getConn();
pstmt = (PreparedStatement) conn.prepareStatement(sql);
rs= (ResultSet) pstmt.executeQuery();
while (rs.next())
{
User user = new User();
user.setUid(rs.getInt("uid"));
user.setUname(rs.getString("uname"));
user.setUpass(rs.getString("upass"));

userList.add(user);
}
}catch (ClassNotFoundException e) {
e.printStackTrace();
}catch (SQLException e) {
e.printStackTrace();
}
return userList;
}

}

6新建 MemcachedManager.java

package memcachedTest;

import java.util.Date;
import java.util.List;

import util.UserDao;
import bean.User;

import com.alisoft.xplatform.asf.cache.memcached.client.MemCachedClient;
import com.alisoft.xplatform.asf.cache.memcached.client.SockIOPool;

public class MemcachedManager {

//创建MemCachedClient全局对象
private static MemCachedClient mcc = new MemCachedClient();

static {
//创建服务器列表及其权重
String[] servers = {"127.0.0.1:11211"};
Integer[] weights = {3};

//创建Socket连接池对象
SockIOPool pool = SockIOPool.getInstance();

//设置服务器信息
pool.setServers(servers);
pool.setWeights(weights);
pool.setFailover(true);

//设置初始连接数、最小和最大连接数以及最大处理时间
pool.setInitConn(5);
pool.setMinConn(5);
pool.setMaxConn(250);
pool.setMaxIdle(1000*60*60*6);

//设置主线程睡眠时间
pool.setMaintSleep(30);

//设置TCP参数、连接超时等
pool.setNagle(false);
pool.setSocketTO(3000);
pool.setSocketConnectTO(0);
pool.setAliveCheck(true);

//初始化连接池
pool.initialize();

//压缩设置，超过指定大小（单位为K）的数据都会被压缩
mcc.setCompressEnable(true);
mcc.setCompressThreshold(64 * 1024);
}

protected MemcachedManager (){

}

//受保护的对象
protected static MemcachedManager instance = new MemcachedManager();

public static MemcachedManager getInstance () {
return instance;
}

public boolean add(String key,Object value) {
return mcc.add(key, value);
}
public boolean add (String key,Object value,Date expiry) {
return mcc.add(key, value,expiry);
}

public boolean replace (String key,Object value) {
return mcc.replace(key, value);
}

public boolean replace (String key,Object value,Date expiry)
{
return mcc.replace(key, value, expiry);
}

public Object get(String key) {
return mcc.get(key);
}

//public static void main(String[] args) {
//// 得到MemcachedManager实例
//MemcachedManager cache = MemcachedManager.getInstance();
//
//// 创建UserDao对象
//UserDao userDao = new UserDao();
//// 查询单个User对象
//User user = userDao.getUserById(4);
//
//// 将User对象添加到缓存中
//cache.add("user", user.getUname());
//
//// 将User对象从缓存中取出来
//String uname = (String)cache.get("user");
//
//System.out.println("从缓存中取出的对象为：" + uname);
//}

@SuppressWarnings({ "unchecked", "rawtypes" })
public static void main(String[] args) {
//得到MemcachedManager实例
MemcachedManager cache = MemcachedManager.getInstance();

//创建UserDao对象
UserDao userDao = new UserDao();
//得到集合对象
List userList = userDao.getUserList();

//创建User对象
User user = null;
for(int i=0; i
{
//循环遍历集合对象
user = (User)userList.get(i);
user.getUid();
user.getUname();
user.getUpass();

//将集合对象存入缓存中
cache.add("userList" + i,user.getUname());

//将集合从缓存中取出
String uname = (String)cache.get("userList"+i);

System.out.println("从缓存中取得的集合为：" + uname);
}
}

}

结果从控制台输出:

从缓存中取得的集合为：uname
从缓存中取得的集合为：uname1
从缓存中取得的集合为：uname2
从缓存中取得的集合为：uname3