# Java 连接 Memcached 服务
使用 Java 程序连接 Memcached，需要在你的 classpath 中添加 Memcached jar 包。
本站 jar 包下载地址：[spymemcached-2.10.3.jar](/try/download/spymemcached-2.10.3.jar)。Google Code jar 包下载地址：[spymemcached-2.10.3.jar](http://code.google.com/p/spymemcached/downloads/list)（需要翻墙）。
以下程序假定 Memcached 服务的主机为 127.0.0.1，端口为 11211。
### 连接实例
Java 连接 Memcached
```
import net.spy.memcached.MemcachedClient;
import java.net.*;
public class MemcachedJava {
public static void main(String[] args) {
try{
// 本地连接 Memcached 服务
MemcachedClient mcc = new MemcachedClient(new InetSocketAddress("127.0.0.1", 11211));
System.out.println("Connection to server sucessful.");
// 关闭连接
mcc.shutdown();
}catch(Exception ex){
System.out.println( ex.getMessage() );
}
}
}
```
该程序中我们使用 InetSocketAddress 连接 IP 为 127.0.0.1 端口 为 11211 的 memcached 服务。
执行以上代码，如果连接成功会输出以下信息：
```
Connection to server successful.
```
### set 操作实例
以下使用 java.util.concurrent.Future 来存储数据
```
import java.net.InetSocketAddress;
import java.util.concurrent.Future;
import net.spy.memcached.MemcachedClient;
public class MemcachedJava {
public static void main(String[] args) {
try{
// 连接本地的 Memcached 服务
MemcachedClient mcc = new MemcachedClient(new InetSocketAddress("127.0.0.1", 11211));
System.out.println("Connection to server sucessful.");
// 存储数据
Future fo = mcc.set("runoob", 900, "Free Education");
// 查看存储状态
System.out.println("set status:" + fo.get());
// 输出值
System.out.println("runoob value in cache - " + mcc.get("runoob"));
// 关闭连接
mcc.shutdown();
}catch(Exception ex){
System.out.println( ex.getMessage() );
}
}
}
```
执行程序，输出结果为：
```
Connection to server successful.
set status:true
runoob value in cache - Free Education
```
### add 操作实例
```
import java.net.InetSocketAddress;
import java.util.concurrent.Future;
import net.spy.memcached.MemcachedClient;
public class MemcachedJava {
public static void main(String[] args) {
try{
// 连接本地的 Memcached 服务
MemcachedClient mcc = new MemcachedClient(new InetSocketAddress("127.0.0.1", 11211));
System.out.println("Connection to server sucessful.");
// 添加数据
Future fo = mcc.set("runoob", 900, "Free Education");
// 打印状态
System.out.println("set status:" + fo.get());
// 输出
System.out.println("runoob value in cache - " + mcc.get("runoob"));
// 添加
Future fo = mcc.add("runoob", 900, "memcached");
// 打印状态
System.out.println("add status:" + fo.get());
// 添加新key
fo = mcc.add("codingground", 900, "All Free Compilers");
// 打印状态
System.out.println("add status:" + fo.get());
// 输出
System.out.println("codingground value in cache - " + mcc.get("codingground"));
// 关闭连接
mcc.shutdown();
}catch(Exception ex){
System.out.println(ex.getMessage());
}
}
}
```
### replace 操作实例
```
import java.net.InetSocketAddress;
import java.util.concurrent.Future;
import net.spy.memcached.MemcachedClient;
public class MemcachedJava {
public static void main(String[] args) {
try {
//连接本地的 Memcached 服务
MemcachedClient mcc = new MemcachedClient(new InetSocketAddress("127.0.0.1", 11211));
System.out.println("Connection to server sucessful.");
// 添加第一个 key=》value 对
Future fo = mcc.set("runoob", 900, "Free Education");
// 输出执行 add 方法后的状态
System.out.println("add status:" + fo.get());
// 获取键对应的值
System.out.println("runoob value in cache - " + mcc.get("runoob"));
// 添加新的 key
fo = mcc.replace("runoob", 900, "Largest Tutorials' Library");
// 输出执行 set 方法后的状态
System.out.println("replace status:" + fo.get());
// 获取键对应的值
System.out.println("runoob value in cache - " + mcc.get("runoob"));
// 关闭连接
mcc.shutdown();
}catch(Exception ex){
System.out.println( ex.getMessage() );
}
}
}
```
### append 操作实例
```
import java.net.InetSocketAddress;
import java.util.concurrent.Future;
import net.spy.memcached.MemcachedClient;
public class MemcachedJava {
public static void main(String[] args) {
try{
// 连接本地的 Memcached 服务
MemcachedClient mcc = new MemcachedClient(new InetSocketAddress("127.0.0.1", 11211));
System.out.println("Connection to server sucessful.");
// 添加数据
Future fo = mcc.set("runoob", 900, "Free Education");
// 输出执行 set 方法后的状态
System.out.println("set status:" + fo.get());
// 获取键对应的值
System.out.println("runoob value in cache - " + mcc.get("runoob"));
// 对存在的key进行数据添加操作
Future fo = mcc.append("runoob", 900, " for All");
// 输出执行 set 方法后的状态
System.out.println("append status:" + fo.get());
// 获取键对应的值
System.out.println("runoob value in cache - " + mcc.get("codingground"));
// 关闭连接
mcc.shutdown();
}catch(Exception ex)
System.out.println(ex.getMessage());
}
}
```
### prepend 操作实例
```
import java.net.InetSocketAddress;
import java.util.concurrent.Future;
import net.spy.memcached.MemcachedClient;
public class MemcachedJava {
public static void main(String[] args) {
try{
// 连接本地的 Memcached 服务
MemcachedClient mcc = new MemcachedClient(new InetSocketAddress("127.0.0.1", 11211));
System.out.println("Connection to server sucessful.");
// 添加数据
Future fo = mcc.set("runoob", 900, "Education for All");
// 输出执行 set 方法后的状态
System.out.println("set status:" + fo.get());
// 获取键对应的值
System.out.println("runoob value in cache - " + mcc.get("runoob"));
// 对存在的key进行数据添加操作
Future fo = mcc.prepend("runoob", 900, "Free ");
// 输出执行 set 方法后的状态
System.out.println("prepend status:" + fo.get());
// 获取键对应的值
System.out.println("runoob value in cache - " + mcc.get("codingground"));
// 关闭连接
mcc.shutdown();
}catch(Exception ex)
System.out.println(ex.getMessage());
}
}
```
### CAS 操作实例
```
import java.net.InetSocketAddress;
import java.util.concurrent.Future;
import net.spy.memcached.CASValue;
import net.spy.memcached.CASResponse;
import net.spy.memcached.MemcachedClient;
public class MemcachedJava {
public static void main(String[] args) {
try{
// 连接本地的 Memcached 服务
MemcachedClient mcc = new MemcachedClient(new InetSocketAddress("127.0.0.1", 11211));
System.out.println("Connection to server sucessful.");
// 添加数据
Future fo = mcc.set("runoob", 900, "Free Education");
// 输出执行 set 方法后的状态
System.out.println("set status:" + fo.get());
// 使用 get 方法获取数据
System.out.println("runoob value in cache - " + mcc.get("runoob"));
// 通过 gets 方法获取 CAS token（令牌）
CASValue casValue = mcc.gets("runoob");
// 输出 CAS token（令牌） 值
System.out.println("CAS token - " + casValue);
// 尝试使用cas方法来更新数据
CASResponse casresp = mcc.cas("runoob", casValue.getCas(), 900, "Largest Tutorials-Library");
// 输出 CAS 响应信息
System.out.println("CAS Response - " + casresp);
// 输出值
System.out.println("runoob value in cache - " + mcc.get("runoob"));
// 关闭连接
mcc.shutdown();
}catch(Exception ex)
System.out.println(ex.getMessage());
}
}
```
### get 操作实例
```
import java.net.InetSocketAddress;
import java.util.concurrent.Future;
import net.spy.memcached.MemcachedClient;
public class MemcachedJava {
public static void main(String[] args) {
try{
// 连接本地的 Memcached 服务
MemcachedClient mcc = new MemcachedClient(new InetSocketAddress("127.0.0.1", 11211));
System.out.println("Connection to server sucessful.");
// 添加数据
Future fo = mcc.set("runoob", 900, "Free Education");
// 输出执行 set 方法后的状态
System.out.println("set status:" + fo.get());
// 使用 get 方法获取数据
System.out.println("runoob value in cache - " + mcc.get("runoob"));
// 关闭连接
mcc.shutdown();
}catch(Exception ex)
System.out.println(ex.getMessage());
}
}
```
### gets 操作实例、CAS
```
import java.net.InetSocketAddress;
import java.util.concurrent.Future;
import net.spy.memcached.CASValue;
import net.spy.memcached.CASResponse;
import net.spy.memcached.MemcachedClient;
public class MemcachedJava {
public static void main(String[] args) {
try{
// 连接本地的 Memcached 服务
MemcachedClient mcc = new MemcachedClient(new InetSocketAddress("127.0.0.1", 11211));
System.out.println("Connection to server sucessful.");
// 添加数据
Future fo = mcc.set("runoob", 900, "Free Education");
// 输出执行 set 方法后的状态
System.out.println("set status:" + fo.get());
// 从缓存中获取键为 runoob 的值
System.out.println("runoob value in cache - " + mcc.get("runoob"));
// 通过 gets 方法获取 CAS token（令牌）
CASValue casValue = mcc.gets("runoob");
// 输出 CAS token（令牌） 值
System.out.println("CAS value in cache - " + casValue);
// 关闭连接
mcc.shutdown();
}catch(Exception ex)
System.out.println(ex.getMessage());
}
}
```
### delete 操作实例
```
import java.net.InetSocketAddress;
import java.util.concurrent.Future;
import net.spy.memcached.MemcachedClient;
public class MemcachedJava {
public static void main(String[] args) {
try{
// 连接本地的 Memcached 服务
MemcachedClient mcc = new MemcachedClient(new InetSocketAddress("127.0.0.1", 11211));
System.out.println("Connection to server sucessful.");
// 添加数据
Future fo = mcc.set("runoob", 900, "World's largest online tutorials library");
// 输出执行 set 方法后的状态
System.out.println("set status:" + fo.get());
// 获取键对应的值
System.out.println("runoob value in cache - " + mcc.get("runoob"));
// 对存在的key进行数据添加操作
Future fo = mcc.delete("runoob");
// 输出执行 delete 方法后的状态
System.out.println("delete status:" + fo.get());
// 获取键对应的值
System.out.println("runoob value in cache - " + mcc.get("codingground"));
// 关闭连接
mcc.shutdown();
}catch(Exception ex)
System.out.println(ex.getMessage());
}
}
```
### Incr/Decr 操作实例
```
import java.net.InetSocketAddress;
import java.util.concurrent.Future;
import net.spy.memcached.MemcachedClient;
public class MemcachedJava {
public static void main(String[] args) {
try{
// 连接本地的 Memcached 服务
MemcachedClient mcc = new MemcachedClient(new InetSocketAddress("127.0.0.1", 11211));
System.out.println("Connection to server sucessful.");
// 添加数字值
Future fo = mcc.set("number", 900, "1000");
// 输出执行 set 方法后的状态
System.out.println("set status:" + fo.get());
// 获取键对应的值
System.out.println("value in cache - " + mcc.get("number"));
// 自增并输出
System.out.println("value in cache after increment - " + mcc.incr("number", 111));
// 自减并输出
System.out.println("value in cache after decrement - " + mcc.decr("number", 112));
// 关闭连接
mcc.shutdown();
}catch(Exception ex)
System.out.println(ex.getMessage());
}
}
```
- Memcached 入门
- Memcached 简介
- Memcached 安装
- Memcached 连接
- Memcached 存储命令
- Memcached set 命令
- Memcached add 命令
- Memcached replace 命令
- Memcached append 命令
- Memcached prepend 命令
- Memcached CAS 命令
- Memcached 查找命令
- Memcached get 命令
- Memcached gets 命令
- Memcached delete 命令
- Memcached incr 与 decr 命令
- Memcached 统计命令
- Memcached stats 命令
- Memcached stats items 命令
- Memcached stats slabs 命令
- Memcached stats sizes 命令
- Memcached flush_all 命令
- Memcached 实例
- Java 连接 Memcached 服务
- PHP 连接 Memcached 服务