http://blog.csdn.net/njchenyi/article/details/9072845
由于需要研究了下用 java socket 传输文件，由于需要传输多个文件，因此，采用了多线程设计。客户端每个线程创建一个 socket 连接，每个 socket 连接负责传输一个文件，服务端的ServerSocket每次 accept 一个 socket 连接，创建一个线程用于接收客户端传来的文件。
1、服务端
import java.io.BufferedInputStream;
import java.io.BufferedOutputStream;
import java.io.DataInputStream;
import java.io.DataOutputStream;
import java.io.FileOutputStream;
import java.net.ServerSocket;
import java.net.Socket;
import java.util.concurrent.ExecutorService;
import java.util.concurrent.Executors;
public class TransferServer {
private int defaultBindPort = Constants.DEFAULT_BIND_PORT; //默认监听端口号为10000
private int tryBindTimes = 0; //初始的绑定端口的次数设定为0
private ServerSocket serverSocket; //服务套接字等待对方的连接和文件发送
private ExecutorService executorService; //线程池
private final int POOL_SIZE = 4; //单个CPU的线程池大小
/**
* 不带参数的构造器，选用默认的端口号
* @throws Exception
*/
public TransferServer() throws Exception{
try {
this.bingToServerPort(defaultBindPort);
executorService = Executors.newFixedThreadPool(Runtime.getRuntime().availableProcessors() * POOL_SIZE);
System.out.println("开辟线程数 ： " + Runtime.getRuntime().availableProcessors() * POOL_SIZE);
} catch (Exception e) {
throw new Exception("绑定端口不成功!");
}
}
/**
* 带参数的构造器，选用用户指定的端口号
* @param port
* @throws Exception
*/
public TransferServer(int port) throws Exception{
try {
this.bingToServerPort(port);
executorService = Executors.newFixedThreadPool(Runtime.getRuntime().availableProcessors() * POOL_SIZE);
} catch (Exception e) {
throw new Exception("绑定端口不成功!");
}
}
private void bingToServerPort(int port) throws Exception{
try {
serverSocket = new ServerSocket(port);
System.out.println(port);
System.out.println("服务启动!");
} catch (Exception e) {
this.tryBindTimes = this.tryBindTimes + 1;
port = port + this.tryBindTimes;
if(this.tryBindTimes >= 20){
throw new Exception("您已经尝试很多次了，但是仍无法绑定到指定的端口!请重新选择绑定的默认端口号");
}
//递归绑定端口
this.bingToServerPort(port);
}
}
public void service(){
Socket socket = null;
while (true) {
try {
socket = serverSocket.accept();
executorService.execute(new Handler(socket));
} catch (Exception e) {
e.printStackTrace();
}
}
}
class Handler implements Runnable{
private Socket socket;
public Handler(Socket socket){
this.socket = socket;
}
public void run() {
System.out.println("New connection accepted " + socket.getInetAddress() + ":" + socket.getPort());
DataInputStream dis = null;
DataOutputStream dos = null;
int bufferSize = 8192;
byte[] buf = new byte[bufferSize];
try {
dis = new DataInputStream(new BufferedInputStream(socket.getInputStream()));
String savePath = Constants.RECEIVE_FILE_PATH + dis.readUTF();
long length = dis.readLong();
dos = new DataOutputStream(new BufferedOutputStream(new FileOutputStream(savePath)));
int read = 0;
long passedlen = 0;
while ((read = dis.read(buf)) != -1) {
passedlen += read;
dos.write(buf, 0, read);
System.out.println("文件[" + savePath + "]已经接收: " + passedlen * 100L/ length + "%");
}
System.out.println("文件: " + savePath + "接收完成!");
} catch (Exception e) {
e.printStackTrace();
System.out.println("接收文件失败!");
}finally{
try {
if(dos != null){
dos.close();
}
if(dis != null){
dis.close();
}
if(socket != null){
socket.close();
}
} catch (Exception e) {
e.printStackTrace();
}
}
}
}
public static void main(String[] args) throws Exception{
new TransferServer().service();
}
}
2、客户端
import java.io.BufferedInputStream;
import java.io.DataInputStream;
import java.io.DataOutputStream;
import java.io.File;
import java.io.FileInputStream;
import java.net.Socket;
import java.util.ArrayList;
import java.util.Random;
import java.util.Vector;
import java.util.concurrent.ExecutorService;
import java.util.concurrent.Executors;
public class TransferClient {
private static ArrayList<String> fileList = new ArrayList<String>();
private String sendFilePath = Constants.SEND_FILE_PATH;
/**
* 带参数的构造器，用户设定需要传送文件的文件夹
* @param filePath
*/
public TransferClient(String filePath){
getFilePath(filePath);
}
/**
* 不带参数的构造器。使用默认的传送文件的文件夹
*/
public TransferClient(){
getFilePath(sendFilePath);
}
public void service(){
ExecutorService executorService = Executors.newCachedThreadPool();
Vector<Integer> vector = getRandom(fileList.size());
for(Integer integer : vector){
String filePath = fileList.get(integer.intValue());
executorService.execute(sendFile(filePath));
}
}
private void getFilePath(String dirPath){
File dir = new File(dirPath);
File[] files = dir.listFiles();
if(files == null){
return;
}
for(int i = 0; i < files.length; i++){
if(files[i].isDirectory()){
getFilePath(files[i].getAbsolutePath());
}
else {
fileList.add(files[i].getAbsolutePath());
}
}
}
private Vector<Integer> getRandom(int size){
Vector<Integer> v = new Vector<Integer>();
Random r = new Random();
boolean b = true;
while(b){
int i = r.nextInt(size);
if(!v.contains(i))
v.add(i);
if(v.size() == size)
b = false;
}
return v;
}
private static Runnable sendFile(final String filePath){
return new Runnable(){
private Socket socket = null;
private String ip ="localhost";
private int port = 10000;
public void run() {
System.out.println("开始发送文件:" + filePath);
File file = new File(filePath);
if(createConnection()){
int bufferSize = 8192;
byte[] buf = new byte[bufferSize];
try {
DataInputStream fis = new DataInputStream(new BufferedInputStream(new FileInputStream(filePath)));
DataOutputStream dos = new DataOutputStream(socket.getOutputStream());
dos.writeUTF(file.getName());
dos.flush();
dos.writeLong(file.length());
dos.flush();
int read = 0;
int passedlen = 0;
long length = file.length(); //获得要发送文件的长度
while ((read = fis.read(buf)) != -1) {
passedlen += read;
System.out.println("已经完成文件 [" + file.getName() + "]百分比: " + passedlen * 100L/ length + "%");
dos.write(buf, 0, read);
}
dos.flush();
fis.close();
dos.close();
socket.close();
System.out.println("文件 " + filePath + "传输完成!");
} catch (Exception e) {
e.printStackTrace();
}
}
}
private boolean createConnection() {
try {
socket = new Socket(ip, port);
System.out.println("连接服务器成功！");
return true;
} catch (Exception e) {
System.out.println("连接服务器失败！");
return false;
}
}
};
}
public static void main(String[] args){
new TransferClient().service();
}
}
3、常量类
public interface Constants {
public final static String RECEIVE_FILE_PATH = "E:\\receive\\";
public final static String SEND_FILE_PATH = "E:\\send";
public final static int DEFAULT_BIND_PORT = 10000;
}