Redis学习02——Jedis使用

一、准备jar包

我们需要使用到的jar包如下

jedis.jar

common-pool

下载地址如下

http://central.maven.org/maven2/redis/clients/jedis/2.9.0/

http://commons.apache.org/proper/commons-pool/download_pool.cgi

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二、创建第一实例程序

private String ipAddress = "172.16.50.145";private int port = 6379;@Testpublic void test1(){    //1.获取链接对象    Jedis jedis = new Jedis(ipAddress,port);    //2.获得数据    String username = jedis.get("username");    System.out.println(username);    //3.存储    jedis.set("addr","上海");    System.out.println(jedis.get("addr"));    jedis.close();}

但是如果你运行你会发现是报超时错，这是因为linux默认没有打开我们的6379端口。具体配置请看下面。

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三、配置服务器

3.1 connect timed out

3.1.1 异常

redis.clients.jedis.exceptions.JedisConnectionException: java.net.SocketTimeoutException: connect timed out    at redis.clients.jedis.Connection.connect(Connection.java:207)    at redis.clients.jedis.BinaryClient.connect(BinaryClient.java:93)    at redis.clients.jedis.Connection.sendCommand(Connection.java:126)    at redis.clients.jedis.Connection.sendCommand(Connection.java:117)    at redis.clients.jedis.Jedis.get(Jedis.java:152)    at com.qwm.redis.Demo1.test1(Demo1.java:25)    at sun.reflect.NativeMethodAccessorImpl.invoke0(Native Method)    at sun.reflect.NativeMethodAccessorImpl.invoke(NativeMethodAccessorImpl.java:62)    at sun.reflect.DelegatingMethodAccessorImpl.invoke(DelegatingMethodAccessorImpl.java:43)    at java.lang.reflect.Method.invoke(Method.java:498)    at org.junit.runners.model.FrameworkMethod$1.runReflectiveCall(FrameworkMethod.java:44)    at org.junit.internal.runners.model.ReflectiveCallable.run(ReflectiveCallable.java:15)    at org.junit.runners.model.FrameworkMethod.invokeExplosively(FrameworkMethod.java:41)    at org.junit.internal.runners.statements.InvokeMethod.evaluate(InvokeMethod.java:20)    at org.junit.runners.ParentRunner.runLeaf(ParentRunner.java:263)    at org.junit.runners.BlockJUnit4ClassRunner.runChild(BlockJUnit4ClassRunner.java:69)    at org.junit.runners.BlockJUnit4ClassRunner.runChild(BlockJUnit4ClassRunner.java:48)    at org.junit.runners.ParentRunner$3.run(ParentRunner.java:231)    at org.junit.runners.ParentRunner$1.schedule(ParentRunner.java:60)    at org.junit.runners.ParentRunner.runChildren(ParentRunner.java:229)    at org.junit.runners.ParentRunner.access$000(ParentRunner.java:50)    at org.junit.runners.ParentRunner$2.evaluate(ParentRunner.java:222)    at org.junit.runners.ParentRunner.run(ParentRunner.java:292)    at org.junit.runner.JUnitCore.run(JUnitCore.java:157)    at com.intellij.junit4.JUnit4IdeaTestRunner.startRunnerWithArgs(JUnit4IdeaTestRunner.java:68)    at com.intellij.rt.execution.junit.IdeaTestRunner$Repeater.startRunnerWithArgs(IdeaTestRunner.java:51)    at com.intellij.rt.execution.junit.JUnitStarter.prepareStreamsAndStart(JUnitStarter.java:242)    at com.intellij.rt.execution.junit.JUnitStarter.main(JUnitStarter.java:70)Caused by: java.net.SocketTimeoutException: connect timed out    at java.net.DualStackPlainSocketImpl.waitForConnect(Native Method)    at java.net.DualStackPlainSocketImpl.socketConnect(DualStackPlainSocketImpl.java:85)    at java.net.AbstractPlainSocketImpl.doConnect(AbstractPlainSocketImpl.java:350)    at java.net.AbstractPlainSocketImpl.connectToAddress(AbstractPlainSocketImpl.java:206)    at java.net.AbstractPlainSocketImpl.connect(AbstractPlainSocketImpl.java:188)    at java.net.PlainSocketImpl.connect(PlainSocketImpl.java:172)    at java.net.SocksSocketImpl.connect(SocksSocketImpl.java:392)    at java.net.Socket.connect(Socket.java:589)    at redis.clients.jedis.Connection.connect(Connection.java:184)    ... 27 more

3.1.2 解决方式

这个是由于linux默认是没有允许访问 6379 端口的，我们需要配置可以访问这个端口。

使用 vim 修改 /etc/sysconfig/iptables

# sample configuration for iptables service# you can edit this manually or use system-config-firewall# please do not ask us to add additional ports/services to this default configuration*filter:INPUT ACCEPT [0:0]:FORWARD ACCEPT [0:0]:OUTPUT ACCEPT [0:0]-A INPUT -m state --state RELATED,ESTABLISHED -j ACCEPT-A INPUT -p icmp -j ACCEPT-A INPUT -i lo -j ACCEPT-A INPUT -p tcp -m state --state NEW -m tcp --dport 22 -j ACCEPT-A INPUT -j REJECT --reject-with icmp-host-prohibited-A FORWARD -j REJECT --reject-with icmp-host-prohibitedCOMMIT

加上一行

-A INPUT -p tcp -m state --state NEW -m tcp --dport 6379 -j ACCEPT

例如

# sample configuration for iptables service# you can edit this manually or use system-config-firewall# please do not ask us to add additional ports/services to this default configuration*filter:INPUT ACCEPT [0:0]:FORWARD ACCEPT [0:0]:OUTPUT ACCEPT [0:0]-A INPUT -m state --state RELATED,ESTABLISHED -j ACCEPT-A INPUT -p icmp -j ACCEPT-A INPUT -i lo -j ACCEPT-A INPUT -p tcp -m state --state NEW -m tcp --dport 22 -j ACCEPT-A INPUT -p tcp -m state --state NEW -m tcp --dport 6379  -j ACCEPT-A INPUT -j REJECT --reject-with icmp-host-prohibited-A FORWARD -j REJECT --reject-with icmp-host-prohibitedCOMMIT

保存重启 iptables

[root@wiming ~]# service iptables restartRedirecting to /bin/systemctl restart  iptables.service

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3.2 java.net.ConnectException: Connection refused: connect

3.2.1 异常

redis.clients.jedis.exceptions.JedisConnectionException: java.net.ConnectException: Connection refused: connect    at redis.clients.jedis.Connection.connect(Connection.java:207)    at redis.clients.jedis.BinaryClient.connect(BinaryClient.java:93)    at redis.clients.jedis.Connection.sendCommand(Connection.java:126)    at redis.clients.jedis.Connection.sendCommand(Connection.java:117)    at redis.clients.jedis.Jedis.get(Jedis.java:152)    at com.qwm.redis.Demo1.test1(Demo1.java:25)    at sun.reflect.NativeMethodAccessorImpl.invoke0(Native Method)    at sun.reflect.NativeMethodAccessorImpl.invoke(NativeMethodAccessorImpl.java:62)    at sun.reflect.DelegatingMethodAccessorImpl.invoke(DelegatingMethodAccessorImpl.java:43)    at java.lang.reflect.Method.invoke(Method.java:498)    at org.junit.runners.model.FrameworkMethod$1.runReflectiveCall(FrameworkMethod.java:44)    at org.junit.internal.runners.model.ReflectiveCallable.run(ReflectiveCallable.java:15)    at org.junit.runners.model.FrameworkMethod.invokeExplosively(FrameworkMethod.java:41)    at org.junit.internal.runners.statements.InvokeMethod.evaluate(InvokeMethod.java:20)    at org.junit.runners.ParentRunner.runLeaf(ParentRunner.java:263)    at org.junit.runners.BlockJUnit4ClassRunner.runChild(BlockJUnit4ClassRunner.java:69)    at org.junit.runners.BlockJUnit4ClassRunner.runChild(BlockJUnit4ClassRunner.java:48)    at org.junit.runners.ParentRunner$3.run(ParentRunner.java:231)    at org.junit.runners.ParentRunner$1.schedule(ParentRunner.java:60)    at org.junit.runners.ParentRunner.runChildren(ParentRunner.java:229)    at org.junit.runners.ParentRunner.access$000(ParentRunner.java:50)    at org.junit.runners.ParentRunner$2.evaluate(ParentRunner.java:222)    at org.junit.runners.ParentRunner.run(ParentRunner.java:292)    at org.junit.runner.JUnitCore.run(JUnitCore.java:157)    at com.intellij.junit4.JUnit4IdeaTestRunner.startRunnerWithArgs(JUnit4IdeaTestRunner.java:68)    at com.intellij.rt.execution.junit.IdeaTestRunner$Repeater.startRunnerWithArgs(IdeaTestRunner.java:51)    at com.intellij.rt.execution.junit.JUnitStarter.prepareStreamsAndStart(JUnitStarter.java:242)    at com.intellij.rt.execution.junit.JUnitStarter.main(JUnitStarter.java:70)Caused by: java.net.ConnectException: Connection refused: connect    at java.net.DualStackPlainSocketImpl.waitForConnect(Native Method)    at java.net.DualStackPlainSocketImpl.socketConnect(DualStackPlainSocketImpl.java:85)    at java.net.AbstractPlainSocketImpl.doConnect(AbstractPlainSocketImpl.java:350)    at java.net.AbstractPlainSocketImpl.connectToAddress(AbstractPlainSocketImpl.java:206)    at java.net.AbstractPlainSocketImpl.connect(AbstractPlainSocketImpl.java:188)    at java.net.PlainSocketImpl.connect(PlainSocketImpl.java:172)    at java.net.SocksSocketImpl.connect(SocksSocketImpl.java:392)    at java.net.Socket.connect(Socket.java:589)    at redis.clients.jedis.Connection.connect(Connection.java:184)    ... 27 more

3.2.2 解决方式

第一步：

注释 redis.conf 中的 bind 127.0.0.1，还是一样使用vim 打开配置文件。找到 69行，修改如下

67 # JUST COMMENT THE FOLLOWING LINE.68 # ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~69 # bind 127.0.0.1

保存,重启redis，在看可一看是时候已经ok了，如果不行，再看第二步

第二步：

修改 redis.conf 中的 88 行**protected-mode no
**，yes 改为no

86 # even if no authentication is configured, nor a specific set of interfaces87 # are explicitly listed using the "bind" directive.88 protected-mode no

保存重启redis,现在就ok了。

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四、打印结果

wiming上海

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五、使用连接池

5.1 代码

@Testpublic void test2(){    //1.创建连接池的配置对象    JedisPoolConfig config = new JedisPoolConfig();    config.setMaxIdle(30);//最大闲置个数    config.setMinIdle(10);//最小闲置个数    config.setMaxTotal(50);//最大连接数    //2.创建连接池    JedisPool pool = new JedisPool(config,ipAddress,port);    //3.从连接池子中获取redis连接    Jedis jedis = pool.getResource();    //4.操作数据库    System.out.println(jedis.get("username"));    //5.关闭资源    jedis.close();    pool.close();}

5.2 结果

wiming

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六、使用配置的使用连接池

我们可以使配置的方式来设置连接池的配置。选用 properties 相对简单好多，所以我们使用这个。

6.1 redis.properties

在src下创建 redis.properties

//最大闲置个数redis.maxIdle=30//最小闲置个数redis.minIdle=10//最大连接数redis.maxTotal=50//主机redis.host=172.16.50.145//端口redis.port=6379

6.2 JedisPoolUtils 连接池工具类

package com.qwm.redis;import redis.clients.jedis.Jedis;import redis.clients.jedis.JedisPool;import redis.clients.jedis.JedisPoolConfig;import java.io.IOException;import java.io.InputStream;import java.util.Properties;/** * @author：qiwenming * @date：2017/9/24 0024   19:43 * @description： * redis连接池工具类 */public class JedisPoolUtils {    private static JedisPool pool = null;    static {        //加载配置文件        InputStream in = JedisPoolUtils.class.getClassLoader().getResourceAsStream("redis.properties");        Properties pro = new Properties();        try {            pro.load(in);            //最大闲置个数            int maxIdle = Integer.parseInt(pro.getProperty("redis.maxIdle"));            //最小闲置个数            int minIdle = Integer.parseInt(pro.getProperty("redis.minIdle"));            //最大连接数            int maxTotal = Integer.parseInt(pro.getProperty("redis.maxTotal"));            //主机            String host = pro.getProperty("redis.host");            //端口            int port = Integer.parseInt(pro.getProperty("redis.port"));            //配置参数            JedisPoolConfig poolConfig = new JedisPoolConfig();            poolConfig.setMaxIdle(maxIdle);            poolConfig.setMinIdle(minIdle);            poolConfig.setMaxTotal(maxTotal);            pool = new JedisPool(poolConfig,host,port);        } catch (IOException e) {            e.printStackTrace();        }    }    /**     * 获得jedis资源的方法     * @return     */    public static Jedis getJedis(){        return pool.getResource();    }}

6.3 测试代码

package com.qwm.redis;import org.junit.Test;import redis.clients.jedis.Jedis;import java.util.Iterator;import java.util.Map;import java.util.Set;/** * @author：qiwenming * @date：2017/9/24 0024   20:00 * @description： */public class Demo2 {    @Test    public void test1(){        Jedis jedis = JedisPoolUtils.getJedis();        System.out.println(jedis.get("username"));        jedis.hset("myhash","s","kkkkkkk");        jedis.hset("myhash","k","fdsafdsafds");        jedis.hset("myhash","v","fdsafdsafds");        //获取myhash中的全部数据        Map<String,String> map =  jedis.hgetAll("myhash");        Set<Map.Entry<String,String>> kv = map.entrySet();        Iterator<Map.Entry<String,String>>  iterator = kv.iterator();        //迭代        while(iterator.hasNext()){            Map.Entry<String,String> entry = iterator.next();            System.out.println(entry.getKey()+"---"+entry.getValue());        }    }}

6.4 结果

wimingv---fdsafdsafdss---kkkkkkkk---fdsafdsafds