java 链接redis demo_java socket 连接redis，解析redis协议

最近复习了一下redis底层传输协议，然后抽时间写了一个例子，话不多说，上代码

package com.example.demo;

import java.io.IOException;

import java.io.InputStream;

import java.io.OutputStream;

import java.net.Socket;

import java.nio.charset.StandardCharsets;

/**

* @author lt

* @date 2019-01-15 10:07:21

*/

public class RedisSocket {

public static void main(String[] args) throws IOException {

String host = "127.0.0.1";

int port = 6379;

Socket socket = new Socket(host, port);

socket.setSoTimeout(3000);

// 建立连接后获得IO出流

OutputStream outputStream = socket.getOutputStream();

InputStream inputStream = socket.getInputStream();

//看过很多是将斜杠转义的写法，是不对的，因为他和r或者n连起来当做命令，而不是单纯的字符串

//redis在处理命令时也做了判断，直接发送redis cli命令也可以解析，但必须以rn或者n结尾

//String message = "*3\r\n$3\r\nSET\r\n$6\r\nsocket\r\n$10\r\nsocketTest\r\n";

getResult(outputStream, inputStream, "*3rn$3rnSETrn$6rnsocketrn$10rnsocketTestrn");

getResult(outputStream, inputStream, "error testrn");

getResult(outputStream, inputStream, "*2rn$3rngetrn$5rnsocketrn");

getResult(outputStream, inputStream, "set socket socketTest1rn");

getResult(outputStream, inputStream, "exists socketrn");

getResult(outputStream, inputStream, "get socketrn");

getResult(outputStream, inputStream, "keys *rn");

getResult(outputStream, inputStream, "get otherTestn");

socket.close();

System.err.println("*****socket closed*****");

}

private static void getResult(OutputStream outputStream, InputStream inputStream, String cmd) throws IOException {

System.err.println("rnsend command : " + cmd.replaceAll("\r\n", " "));

outputStream.write(cmd.getBytes(StandardCharsets.UTF_8));

outputStream.flush();

//此写法是为了测试，不适合返回数据太多的情况

byte[] bytes = new byte[128];

int length = inputStream.read(bytes);

String result = new String(bytes, 0, length, StandardCharsets.UTF_8);

while (result.length() > 0) {

int index = result.indexOf("rn");

//取第一个命令

String currentStr = result.substring(0, index);

//剩余命令，注意：rn占两个长度

result = result.substring(index + 2);

if (currentStr.startsWith("+")) {

System.err.println("+ status reply message：" + currentStr.substring(1));

} else if (currentStr.startsWith("-")) {

System.err.println("- error reply message：" + currentStr.substring(1));

} else if (currentStr.startsWith(":")) {

System.err.println(": integer reply message：" + currentStr.substring(1));

} else if (currentStr.startsWith("$")) {

System.err.println("$ bulk reply message：" + currentStr.substring(1));

} else if (currentStr.startsWith("*")) {

System.err.println("* multi bulk reply message：" + currentStr.substring(1));

}else {

System.err.println("other message : " + currentStr);

}

}

}

}

需要注意的地方看里面注释说明吧，不多说了

redis版本是3.2.100

更详细的请看文档：http://redisdoc.com/topic/protocol.html

http://www.redis.cn/topics/protocol.html

欢迎转载，转载请注明出处，谢谢！！！