用java写服务器端_java编写服务器端

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文章目录:

用java编写app的服务器端,需要用到什么技术和框架

看你要编写什么程度的东西了,如果是最常见的HTTP接口,那么java ee技术会很方便,现在主流的框架也很多,比如Sring mvc,struts2,hibernate,mybaits等等,不要被那么东西吓到,本质思想是一样的,只是写法不一样,你随便先熟悉哪个都可以写出不错的服务器代码。

至于其他的,那么就要了解java底层的Thread,socket等级技术,还要了解一些连接规范,比如ftp啊啥的,看具体需求了,这个要求比之前的高的多也底层的多了。

java编写一个客户/服务器程序

下面是我自己写的一个读取并显示txt文件的demo,希望对您有帮助。

public class Client {

public static void main(String[] args) {

ClientFrame f = new ClientFrame();

}

}

import java.awt.BorderLayout;

import java.awt.Container;

import java.awt.Dimension;

import java.awt.GridLayout;

import java.awt.Toolkit;

import java.awt.event.ActionEvent;

import java.awt.event.ActionListener;

import java.io.DataInputStream;

import java.io.DataOutputStream;

import java.io.IOException;

import java.net.Socket;

import java.net.UnknownHostException;

import java.util.Vector;

import javax.swing.BorderFactory;

import javax.swing.JButton;

import javax.swing.JFrame;

import javax.swing.JList;

import javax.swing.JScrollPane;

import javax.swing.JTextArea;

import javax.swing.event.ListSelectionEvent;

import javax.swing.event.ListSelectionListener;

public class ClientFrame extends JFrame implements ActionListener, ListSelectionListener{

private JList list = null;

private JButton sbtn = null;

private JButton cbtn = null;

private Vector v = null;

private JTextArea txt = null;

private Container control = null;

private Container btn = null;

private Socket client = null;

private DataInputStream reader = null;

private DataOutputStream writer = null;

public ClientFrame(){

this.list = new JList();

this.list.setBorder(BorderFactory.createTitledBorder("文件列表"));

this.list.addListSelectionListener(this);

this.sbtn = new JButton("显示");

this.sbtn.addActionListener(this);

this.cbtn = new JButton("清除");

this.cbtn.addActionListener(this);

this.control = new Container();

this.control.setPreferredSize(new Dimension(150, 400));

this.control.setLayout(new BorderLayout());

this.control.add(new JScrollPane(this.list),BorderLayout.CENTER);

this.btn = new Container();

this.btn.setLayout(new GridLayout(1,2));

btn.add(sbtn);

btn.add(cbtn);

this.control.add(this.btn,BorderLayout.SOUTH);

this.txt = new JTextArea();

this.txt.setEditable(false);

this.txt.setSize(350, 400);

this.setTitle("客户端");

this.setSize(500, 400);

this.setVisible(true);

Dimension displaySize = Toolkit.getDefaultToolkit().getScreenSize();

this.setLocation((displaySize.width - this.getWidth()) / 2, (displaySize.height - this.getHeight()) / 2);

this.setLayout(new BorderLayout());

this.add(this.control,BorderLayout.WEST);

this.add(new JScrollPane(this.txt),BorderLayout.CENTER);

this.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);

try {

//this.client = new Socket("192.168.32.34",6666);

this.client = new Socket("192.168.1.100",6666);

this.reader = new DataInputStream(client.getInputStream());

this.writer = new DataOutputStream(client.getOutputStream());

} catch (UnknownHostException e) {

e.printStackTrace();

} catch (IOException e) {

e.printStackTrace();

}

}

public void actionPerformed(ActionEvent event){

if(event.getSource() == sbtn){

if(v == null){

v = new Vector();

}

else{

v.clear();

}

try {

writer.writeUTF("getfilelist");

writer.flush();

String t = reader.readUTF();

while( t != null !t.equals("")){

v.add(t);

t = reader.readUTF();

}

} catch (UnknownHostException e) {

e.printStackTrace();

} catch (IOException e) {

e.printStackTrace();

}

this.list.setListData(v);

}

if(event.getSource() == cbtn){

this.txt.setText("");

}

}

public void valueChanged(ListSelectionEvent e) {

int i = this.list.getSelectedIndex();

if (! this.list.getValueIsAdjusting() i != -1) {

try {

writer.writeUTF("getfilecontent_" + i);

writer.flush();

String tmp = reader.readUTF();

this.txt.setText(tmp);

} catch (IOException e1) {

e1.printStackTrace();

}

}

}

}

import java.io.DataInputStream;

import java.io.DataOutputStream;

import java.io.File;

import java.io.FileInputStream;

import java.io.IOException;

import java.io.InputStreamReader;

import java.io.Reader;

import java.net.ServerSocket;

import java.net.Socket;

import java.util.ArrayList;

import java.util.Iterator;

public class Server {

static ArrayListFile fileArray = new ArrayListFile();

public static void main(String args[]) {

ServerSocket server = null;

Socket client = null;

String cmd = "";

try {

server = new ServerSocket(6666);

client = server.accept();

DataInputStream reader = new DataInputStream(client.getInputStream());

DataOutputStream writer = new DataOutputStream(client.getOutputStream());

while(true){

cmd = reader.readUTF();

System.out.println(cmd);

if(cmd.equals("getfilelist")){

fileArray.clear();

//fileArray = getFile(new File("D:/tmp"));

fileArray = getFile(new File("D:/学习/教程/学习笔记"));

String fn = "";

for(int k = 0; k fileArray.size(); k ++){

fn = fileArray.get(k).getName();

writer.writeUTF(fn);

writer.flush();

}

writer.writeUTF("");

}

if(cmd.startsWith("getfilecontent_")){

int i = Integer.parseInt(cmd.split("_")[1]);

File f = fileArray.get(i);

Reader in = new InputStreamReader(new FileInputStream(f));

int tempbyte;

String str = "";

while ((tempbyte = in.read()) != -1) {

str += (char)tempbyte;

//System.out.println(str);

}

in.close();

writer.writeUTF(str);

}

}

} catch (IOException e) {

e.printStackTrace();

}

}

private static ArrayListFile getFile(File f) {

File[] ff = f.listFiles();

for (File child : ff) {

if (child.isDirectory()) {

getFile(child);

} else {

fileArray.add(child);

}

}

return fileArray;

}

}

求用java写一个ftp服务器客户端程序。

import java.io.*;

import java.net.*;public class ftpServer extends Thread{ public static void main(String args[]){

String initDir;

initDir = "D:/Ftp";

ServerSocket server;

Socket socket;

String s;

String user;

String password;

user = "root";

password = "123456";

try{

System.out.println("MYFTP服务器启动....");

System.out.println("正在等待连接....");

//监听21号端口

server = new ServerSocket(21);

socket = server.accept();

System.out.println("连接成功");

System.out.println("**********************************");

System.out.println("");

InputStream in =socket.getInputStream();

OutputStream out = socket.getOutputStream();

DataInputStream din = new DataInputStream(in);

DataOutputStream dout=new DataOutputStream(out);

System.out.println("请等待验证客户信息....");

while(true){

s = din.readUTF();

if(s.trim().equals("LOGIN "+user)){

s = "请输入密码:";

dout.writeUTF(s);

s = din.readUTF();

if(s.trim().equals(password)){

s = "连接成功。";

dout.writeUTF(s);

break;

}

else{s ="密码错误,请重新输入用户名:";br dout.writeUTF(s);br br }

}

else{

s = "您输入的命令不正确或此用户不存在,请重新输入:";

dout.writeUTF(s);

}

}

System.out.println("验证客户信息完毕...."); while(true){

System.out.println("");

System.out.println("");

s = din.readUTF();

if(s.trim().equals("DIR")){

String output = "";

File file = new File(initDir);

String[] dirStructure = new String[10];

dirStructure= file.list();

for(int i=0;idirStructure.length;i++){

output +=dirStructure[i]+"\n";

}

s=output;

dout.writeUTF(s);

}

else if(s.startsWith("GET")){

s = s.substring(3);

s = s.trim();

File file = new File(initDir);

String[] dirStructure = new String[10];

dirStructure= file.list();

String e= s;

int i=0;

s ="不存在";

while(true){

if(e.equals(dirStructure[i])){

s="存在";

dout.writeUTF(s);

RandomAccessFile outFile = new RandomAccessFile(initDir+"/"+e,"r");

byte byteBuffer[]= new byte[1024];

int amount;

while((amount = outFile.read(byteBuffer)) != -1){

dout.write(byteBuffer, 0, amount);break;

}break;

}

else if(idirStructure.length-1){

i++;

}

else{

dout.writeUTF(s);

break;

}

}

}

else if(s.startsWith("PUT")){

s = s.substring(3);

s = s.trim();

RandomAccessFile inFile = new RandomAccessFile(initDir+"/"+s,"rw");

byte byteBuffer[] = new byte[1024];

int amount;

while((amount =din.read(byteBuffer) )!= -1){

inFile.write(byteBuffer, 0, amount);break;

}

}

else if(s.trim().equals("BYE"))break;

else{

s = "您输入的命令不正确或此用户不存在,请重新输入:";

dout.writeUTF(s);

}

}

din.close();

dout.close();

in.close();

out.close();

socket.close();

}

catch(Exception e){

System.out.println("MYFTP关闭!"+e);

}

}}

用java编写app的服务器端,需要用到什么技术和框架?

首先,App的服务端跟Web的服务端没有多大区别,而且在实际的开发过程中,业务逻辑也都是共用一套,只是会针对不同的客户端做不同的适配。其次,既然与Web的服务端没多大区别,那所用的技术也大同小异,对于App而言,服务端更多是一个数据接口,所以框架页大同小异;

技术:

网络通信:tcp,http等;

Web服务:servlet,cgi脚本,asp等;

系统调度:多线程,并发等;

框架:

对应不同的web服务技术,采用的编程语言不同;

对应不同的网络通信协议,采用的框架也不同,netty-tcp,servlet等web服务框架-http等;

对应系统调度,有不同的多线程,多进程通信框架等;

对应提供不同的服务接口,有webservice和restful两大类,前者基于soap协议,后者基于http协议,对应的框架就很多,不一一叙述;

用java编写app的服务器端要学哪些东西

首先,App的服务端跟Web的服务端没有多大区别,而且在实际的开发过程中,业务逻辑也都是共用一套,只是会针对不同的客户端做不同的适配(这点可参考Amazon,其对PC的web端,移动的Web端,移动的App都做了不同程度的适配).

其次,既然与Web的服务端没多大区别,那所用的技术也大同小异,对于App而言,服务端更多是一个数据接口,所以框架页大同小异;

最后,大致总结一下:

技术:

网络通信: tcp,http等;

Web服务:servlet, cgi脚本,asp等;

系统调度:多线程,并发等;

框架:

对应不同的web服务技术,采用的编程语言不同;

对应不同的网络通信协议,采用的框架也不同,netty-tcp,servlet等web服务框架-http等;

对应系统调度,有不同的多线程,多进程通信框架等;

对应提供不同的服务接口,有web service和restful两大类,前者基于soap协议,后者基于http协议,对应的框架就很多,不一一叙述;

4条大神的评论

  • avatar
    访客 2022-07-02 上午 01:55:25

    t文件的demo,希望对您有帮助。public class Client { public static void main(String[] args) { ClientFrame f = new ClientFrame(); }}import java.awt.Bord

  • avatar
    访客 2022-07-01 下午 04:12:16

    ; this.control.add(new JScrollPane(this.list),BorderLayout.CENTER); this.btn = new Container(); this.btn.set

  • avatar
    访客 2022-07-01 下午 05:35:53

    ew Socket("192.168.32.34",6666); this.client = new Socket("192.168.1.100",6666); this.reader = new DataInpu

  • avatar
    访客 2022-07-01 下午 03:11:02

    er[]= new byte[1024]; int amount; while((amount = outFile.read(byteBuffer)) != -1){ dout.write(byteBuffer, 0, amount);break;

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