客户端:
Client.java
package lee.socket;
import java.io.BufferedInputStream;
import java.io.DataInputStream;
import java.io.DataOutputStream;
import java.io.File;
import java.io.FileInputStream;
import java.io.IOException;
import java.net.Socket;
public class Client {
static DataInputStream din = null;
static DataOutputStream dout = null;
static Socket s = null;
public static void main(String[] args) {
try {
s = new Socket("127.0.0.1", 2224);
File file = new File("d:/05.jpg"); // 定义文件
FileInputStream fis = new FileInputStream(file); // 定义文件输入流
din = new DataInputStream(new BufferedInputStream(fis)); // 用缓存流包装文件输入流(提高读取速度),然后再包装成数据输入流
dout = new DataOutputStream(s.getOutputStream());// 定义数据输出流
dout.writeUTF(String.valueOf(file.length())); // 发送文件长度
byte[] buffer = new byte[1024]; // 定义缓存
int len = 0;
while ((len = din.read(buffer)) != -1) {
dout.write(buffer, 0, len); // 向服务器发送数据
}
dout.flush();
} catch (IOException e) {
System.out.println(e.toString());
} finally {
try {
if (din != null) {
din.close();
din = null;
}
} catch (Exception e) {
e.printStackTrace();
}
try {
if (dout != null) { // 最后一定要关闭输出流,不然数据发送不出去。导致一直连接着,不断开
dout.close();
dout = null;
}
} catch (Exception e) {
e.printStackTrace();
}
try {
if (s != null) {
s.close();
s = null;
}
} catch (Exception e) {
e.printStackTrace();
}
}
}
}
Android和客户端基本一样。
服务端:
Server.java
package lee.socket;
import java.io.BufferedInputStream;
import java.io.BufferedOutputStream;
import java.io.DataInputStream;
import java.io.DataOutputStream;
import java.io.File;
import java.io.FileOutputStream;
import java.io.IOException;
import java.net.ServerSocket;
import java.net.Socket;
public class Server {
static DataInputStream din = null;
static DataOutputStream dout = null;
static Socket s = null;
public static void main(String[] args) {
new Thread() { // 开启子线程
public void run() {
try {
ServerSocket ss = new ServerSocket(2224); // 这个必须在while外,不然会循环连接端口,出错
while (true) {
System.out.println("--------等待用户连接--------------");
s = ss.accept();
System.out.println("--------用户连接上了--------------");
din = new DataInputStream(new BufferedInputStream(s
.getInputStream()));// 使用缓存进行包装,提示读取速度
System.out.println("文件长度:" + din.readUTF()); // 显示接收文件长度
File file = new File("d:/01.jpg");
FileOutputStream fos = new FileOutputStream(file);
dout = new DataOutputStream(new BufferedOutputStream(
fos));
byte[] buffer = new byte[1024];
int len = 0;
while ((len = din.read(buffer)) != -1) {
dout.write(buffer, 0, len);
}
dout.flush();
dout.close(); // 下面的finally要等到循环结束后才执行,如果不执行close,文件无法正常打开
System.out.println("接受成功");
}
} catch (IOException e) {
e.printStackTrace();
} finally { // 等while循环结束后才会执行,
try {
if (dout != null) {
dout.close();
dout = null;
}
} catch (Exception e) {
e.printStackTrace();
}
try {
if (din != null) {
din.close();
din = null;
}
} catch (Exception e) {
e.printStackTrace();
}
try {
if (s != null) {
s.close();
s = null;
}
} catch (Exception e) {
e.printStackTrace();
}
}
}
}.start();
}
}