java与c/c++进行socket通信

比如Server端只接收一个结构Employee，定义如下：

struct UserInfo {
char UserName[20];
int UserId;
};
struct Employee {
UserInfo user;
float salary;
};
当然也可以定义为

struct Employee {
char name[20];
int id;
float salary;
};

java client 测试源码(为说明问题，假设struct字节对齐，sizeof(Employee)=28)

import java.net.*;
/**
* 与C语言通信(java做Client，c/c++做Server，传送一个结构)
* @author kingfish
* @version 1.0
*/
class Employee {
private byte[] buf = new byte[28]; //为说明问题，定死大小，事件中可以灵活处理
/**
   * 将int转为低字节在前，高字节在后的byte数组
   */
private static byte[] toLH(int n) {
    byte[] b = new byte[4];
    b[0] = (byte) (n & 0xff);
    b[1] = (byte) (n >> 8 & 0xff);
    b[2] = (byte) (n >> 16 & 0xff);
    b[3] = (byte) (n >> 24 & 0xff);
    return b;
}
/**
   * 将float转为低字节在前，高字节在后的byte数组
   */
private static byte[] toLH(float f) {
    return toLH(Float.floatToRawIntBits(f));
}
/**
   * 构造并转换
   */
public Employee(String name, int id, float salary) {
    byte[] temp = name.getBytes();
    System.arraycopy(temp, 0, buf, 0, temp.length);
    temp = toLH(id);
    System.arraycopy(temp, 0, buf, 20, temp.length);
    temp = toLH(salary);
    System.arraycopy(temp, 0, buf, 24, temp.length);
}
/**
   * 返回要发送的数组
   */
public byte[] getBuf() {
    return buf;
}
/**
   * 发送测试
   */
public static void main(String[] args) {
    try {
      Socket sock = new Socket("127.0.0.1", 8888);
      sock.getOutputStream().write(new Employee("kingfish", 123456789, 8888.99f).
                                   getBuf());
      sock.close();
    }
    catch (Exception e) {
      e.printStackTrace();
    }
} //end

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当然，也可以利用writeInt,writeFloat方法发送，但字节顺序需要改为低在前。
这个问题稍后在讨论。

如有任何问题，请指正！

对于java端的接收有些问题，

我列出我们以前的接收函数：

public String Receive() throws IOException
{
    byte[] buffer = new byte[8];//byte[1024]
       int count = 0;
       ips=_Socket.getInputStream();
       ios=new DataInputStream(ips);
       if (listMsg.size() == 0)
       {
           count=ios.read(buffer, 0, buffer.length);//获取字符数组和其长度
           String str=new String(buffer,0,count,"gb2312");//转换成字符串
           String[] strs=str.split("//|");
          for (int i = 0; i < strs.length; i++)
          {
              if (strs[i].toString() != "")
              {
                  listMsg.add(strs[i]);
              }
          }
          str = listMsg.get(0).toString().trim();
          listMsg.remove(0);
          buffer = null;
          return str;
       }
       else
       {
        String str = listMsg.get(0).toString().trim();
           listMsg.remove(0);
           buffer = null;
           return str;
       }
}

接收流函数：

/*
* 接收流，注意流的大小，避免溢出
* linc
* 2010-9-13
*/
public byte[] ReceiveStream() throws Exception
{
    String str = Receive();
       int num = Integer.parseInt(str);//获得流的长度
       Send("0|",false);
       ByteArrayOutputStream _bytestream=new ByteArrayOutputStream();
       InputStream _InputStream=_Socket.getInputStream();
       int Length=0;
       byte[] buffer = new byte[1024];
       while (Length < num)
       {
        int temp_length = buffer.length;//1024
            if ((num - Length) < temp_length)
            {
                temp_length = num - Length;
            }
            _InputStream.read(buffer, 0, temp_length);
            _bytestream.write(buffer, 0, temp_length);

补充：软件开发 , Java ,