近日，有一需求，向连接在内网的继电器发送socket请求，加以控制。原本并不复杂，只是io流/socket转换的问题，实操中却出现python代码没问题，java代码执行无响应的问题，问题很好定位：没有发送正确的请求指令。进而确定是编码的问题，python预设全局编码格式为utf-8，java端只需指定请求字节码为utf-8即可。

python实现： 

#! /usr/bin/env python# -*- coding:utf-8 -*-# __author__ = "NYA"import socketsoc = socket.socket(socket.AF_INET,socket.SOCK_STREAM)address=('172.18.20.188',5002)soc.connect(address)message="on1"message="off1"message="read1"#res=soc.recv(512)#print ressoc.send(message)total=[]i=0while True:    res=soc.recv(1)    if i>8:        total.append(res)    i+=1    if str(res)=='1': break#print resthen=''.join(total)print thensoc.close()

java实现：

import java.io.*;import java.net.Socket;import java.util.regex.Pattern;public class TestSocket {    public static void main(String[] args) {        /*        * command:        *   on1 off1 read1        *   on2 off2 read2        * */        try {            BufferedReader input = new BufferedReader(new InputStreamReader(System.in));            boolean flag = true;            while (flag) {                System.out.println("输入信息： ");                String str = input.readLine();                if ("bye".equals(str)) {                    flag = false;                } else {                    String s = sendCommand(str);                    System.out.println(s);                }            }            input.close();            System.err.println("good bye");        } catch (Exception e) {            e.printStackTrace();        }    }    public static String sendCommand(String command) {        String result;        String ip = "172.18.20.188";        int port = 5000;        Socket socket = null;        try {            socket = new Socket(ip,port);            socket.setSoTimeout(1000); // read 超时            OutputStream outputStream = socket.getOutputStream();            byte[] receive = new byte[1];            byte[] bytes = command.getBytes("UTF-8"); // 转码 ×××            outputStream.write(bytes);            InputStream inputStream = socket.getInputStream();            StringBuilder sb = new StringBuilder();            int i = 0 ;            while (true) {                inputStream.read(receive);                String now = new String(receive);                if (i > 8) sb.append(now);                if (i > 10) {                    if (isInteger(now)) break;                }                i++;            }            result =  sb.toString();        } catch (Exception e) {            //e.printStackTrace();            result="err";        }        // 释放socket连接        try {            socket.close();        } catch (IOException e) {            e.printStackTrace();        }        return result;    }    public static boolean isInteger(String str) {        Pattern pattern = Pattern.compile("^[-\\+]?[\\d]*$");        return pattern.matcher(str).matches();    }}