使用java代码操作Redis
1. Java访问redis
2.1 添加依赖
<dependency><groupId>redis.clients</groupId>
<artifactId>jedis</artifactId>
<version>2.9.0</version>
</dependency>
1 <?xml version="1.0" encoding="UTF-8"?> 2 3 <project xmlns="http://maven.apache.org/POM/4.0.0" xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance" 4 xsi:schemaLocation="http://maven.apache.org/POM/4.0.0 http://maven.apache.org/xsd/maven-4.0.0.xsd"> 5 <modelVersion>4.0.0</modelVersion> 6 7 <groupId>com.yuan</groupId> 8 <artifactId>redis01</artifactId> 9 <version>1.0-SNAPSHOT</version> 10 <packaging>war</packaging> 11 12 <name>redis01 Maven Webapp</name> 13 <!-- FIXME change it to the project's website --> 14 <url>http://www.example.com</url> 15 16 <properties> 17 <project.build.sourceEncoding>UTF-8</project.build.sourceEncoding> 18 <maven.compiler.source>1.7</maven.compiler.source> 19 <maven.compiler.target>1.7</maven.compiler.target> 20 </properties> 21 22 <dependencies> 23 <dependency> 24 <groupId>junit</groupId> 25 <artifactId>junit</artifactId> 26 <version>4.12</version> 27 <scope>test</scope> 28 </dependency> 29 <dependency> 30 <groupId>redis.clients</groupId> 31 <artifactId>jedis</artifactId> 32 <version>2.9.0</version> 33 </dependency> 34 </dependencies> 35 36 <build> 37 <finalName>redis01</finalName> 38 <pluginManagement><!-- lock down plugins versions to avoid using Maven defaults (may be moved to parent pom) --> 39 <plugins> 40 <plugin> 41 <artifactId>maven-clean-plugin</artifactId> 42 <version>3.1.0</version> 43 </plugin> 44 <!-- see http://maven.apache.org/ref/current/maven-core/default-bindings.html#Plugin_bindings_for_war_packaging --> 45 <plugin> 46 <artifactId>maven-resources-plugin</artifactId> 47 <version>3.0.2</version> 48 </plugin> 49 <plugin> 50 <artifactId>maven-compiler-plugin</artifactId> 51 <version>3.8.0</version> 52 </plugin> 53 <plugin> 54 <artifactId>maven-surefire-plugin</artifactId> 55 <version>2.22.1</version> 56 </plugin> 57 <plugin> 58 <artifactId>maven-war-plugin</artifactId> 59 <version>3.2.2</version> 60 </plugin> 61 <plugin> 62 <artifactId>maven-install-plugin</artifactId> 63 <version>2.5.2</version> 64 </plugin> 65 <plugin> 66 <artifactId>maven-deploy-plugin</artifactId> 67 <version>2.8.2</version> 68 </plugin> 69 </plugins> 70 </pluginManagement> 71 </build> 72 </project>
2.2 Java连接redis
Jedis jedis = new Jedis(ip, port);jedis.auth("123456");//权限认证
jedis.ping();
jedis.select(0);//切换数据库
package com.yuan;
import redis.clients.jedis.Jedis;
import java.util.Map;
/**
* 讲解java代码操作redis
* String、hash、list
*
*
* 1、加载驱动
* 2、建立连接(url/uname/pwd)
* 3、preparestatement
* 4、执行sql
* 5、处理结果
* 6、关闭资源
*
* redis连接步骤
* 1、建立连接,连接后授权
* 2、使用redis
*
*
*/
public class Demo1 {
public static void main(String[] args) {
//连接redis
Jedis jedis = new Jedis("192.168.238.129",6379);
jedis.auth("123456");
System.out.println(jedis.ping());
}
}
2.3 Java操作redis
string(字符串)hash(哈希)
list(列表)
注1:不需要记得API的方法,只需要查redis命令
package com.yuan;
import redis.clients.jedis.Jedis;
import java.util.Map;
/**
* 讲解java代码操作redis
* String、hash、list
*
*
* 1、加载驱动
* 2、建立连接(url/uname/pwd)
* 3、preparestatement
* 4、执行sql
* 5、处理结果
* 6、关闭资源
*
* redis连接步骤
* 1、建立连接,连接后授权
* 2、使用redis
*
*
*/
public class Demo1 {
public static void main(String[] args) {
//连接redis
Jedis jedis = new Jedis("192.168.238.129",6379);
jedis.auth("123456");
System.out.println(jedis.ping());
/*
string
*/
// jedis.set("name","zs");
// jedis.set("age","22");
// System.out.println(jedis.get("name"));
/*
hash
*/
// jedis.hset("user1","uname","ls");
// jedis.hset("user1","pwd","123456");
// jedis.hset("user1","sex","nv");
// System.out.println(jedis.hget("user1","uname"));
// Map<String,String> user1 = jedis.hgetAll("user1");
// for (Map.Entry<String, String> entry :user1.entrySet()){
// System.out.println("key:"+entry.getKey()+",value:"+entry.getValue());
// }
/*
list
*/
// jedis.lpush("hobby","a","b","c","d","e","f","g");
// System.out.println(jedis.lpop("hobby"));
// System.out.println(jedis.rpop("hobby"));
}
}
DemoServlet
1 package com.yuan;
2
3 import redis.clients.jedis.Jedis;
4
5 import javax.servlet.ServletException;
6 import javax.servlet.annotation.WebServlet;
7 import javax.servlet.http.HttpServlet;
8 import javax.servlet.http.HttpServletRequest;
9 import javax.servlet.http.HttpServletResponse;
10 import java.io.IOException;
11
12
13 @WebServlet("/list")
14 public class DemoServlet extends HttpServlet {
15 @Override
16 protected void doGet(HttpServletRequest req, HttpServletResponse resp) throws ServletException, IOException {
17 doPost(req,resp);
18 }
19
20 @Override
21 protected void doPost(HttpServletRequest req, HttpServletResponse resp) throws ServletException, IOException {
22 // 首页第一次是读取数据库,后面读取缓存(在没有增删改的情况)
23 //首页第一次是读取数据库,后面读取缓存
24 Jedis jedis=new Jedis("192.168.47.129",6379);
25 jedis.auth("123456");
26
27 String booklist = jedis.get("booklist");
28 if(booklist==null || "".equals(booklist)){
29 //查询数据库
30 String mysqlData="data";
31 //将mysqldata转成json数组串
32 jedis.set("booklist",mysqlData);
33 booklist = jedis.get("booklist");
34 //第一次登录,访问数据库
35 req.setAttribute("mag","从数据库拿数据");
36 req.setAttribute("booklist",booklist);
37 req.getRequestDispatcher("/booklist.jsp").forward(req,resp);
38 }else{
39 //从缓存获取当前信息
40 req.setAttribute("mag","直接从redis中取得数据");
41 req.setAttribute("booklist",booklist);
42 req.getRequestDispatcher("/booklist.jsp").forward(req,resp);
43 }
44 }
45 }
booklist.jsp代码
1 <%--
2 Created by IntelliJ IDEA.
3 User: 刘源
4 Date: 2019/10/14
5 Time: 1:52
6 To change this template use File | Settings | File Templates.
7 --%>
8 <%@ page contentType="text/html;charset=UTF-8" language="java" %>
9 <%@ page isELIgnored="false" %>
10 <html>
11 <head>
12 <title>Title</title>
13 </head>
14 <body>
15 ${mag}:${booklist}
16 </body>
17 </html>
谢谢观看!!!如需跟详细的讲解请百度查找redis的教程。