客户端
//---------------VerySimpleClient.java
package SocketExample;
// Tue Nov 2 18:34:53 EST 2004
//
// Written by Sean R. Owens, sean at guild dot net, released to the
// public domain. Share and enjoy. Since some people argue that it is
// impossible to release software to the public domain, you are also free
// to use this code under any version of the GPL, LPGL, or BSD licenses,
// or contact me for use of another license.
// http://darksleep.com/player
import java.net.Socket;
import java.net.ServerSocket;
import java.io.InputStream;
import java.io.OutputStream;
import java.io.IOException;
public class VerySimpleClient {
private String serverHostname = null;
private int serverPort = 0;
private byte[] data = null;
private Socket sock = null;
private InputStream sockInput = null;
private OutputStream sockOutput = null;
public VerySimpleClient(String serverHostname, int serverPort, byte[] data){
this.serverHostname = serverHostname;
this.serverPort = serverPort;
this.data = data;
}
public void sendSomeMessages(int iterations) {
System.err.println("Opening connection to "+serverHostname+" port "+serverPort);
try {
sock = new Socket(serverHostname, serverPort);
sockInput = sock.getInputStream();
sockOutput = sock.getOutputStream();
}
catch (IOException e){
e.printStackTrace(System.err);
return;
}
System.err.println("About to start reading/writing to/from socket.");
byte[] buf = new byte[data.length];
int bytes_read = 0;
for(int loopi = 1; loopi <= iterations; loopi++) {
try {
sockOutput.write(data, 0, data.length);
bytes_read = sockInput.read(buf, 0, buf.length);
}
catch (IOException e){
e.printStackTrace(System.err);
}
if(bytes_read < data.length) {
System.err.println("run: Sent "+data.length+" bytes, server should have sent them back, read "+bytes_read+" bytes, not the same number of bytes.");
}
else {
System.err.println("Sent "+bytes_read+" bytes to server and received them back again, msg = "+(new String(data)));
}
// Sleep for a bit so the action doesn't happen to fast - this is purely for reasons of demonstration, and not required technically.
try { Thread.sleep(50);} catch (Exception e) {};
}
System.err.println("Done reading/writing to/from socket, closing socket.");
try {
sock.close();
}
catch (IOException e){
System.err.println("Exception closing socket.");
e.printStackTrace(System.err);
}
System.err.println("Exiting.");
}
public static void main(String argv[]) {
String hostname = "localhost";
int port = 54321;
byte[] data = "Hello World".getBytes();
VerySimpleClient client = new VerySimpleClient(hostname, port, data);
client.sendSomeMessages(100);
}
}
//-------------VerySimpleServer.java
package SocketExample;
// Tue Nov 2 18:33:43 EST 2004
//
// Written by Sean R. Owens, sean at guild dot net, released to the
// public domain. Share and enjoy. Since some people argue that it is
// impossible to release software to the public domain, you are also free
// to use this code under any version of the GPL, LPGL, or BSD licenses,
// or contact me for use of another license.
// http://darksleep.com/player
import java.net.Socket;
import java.net.ServerSocket;
import java.io.InputStream;
import java.io.OutputStream;
import java.io.IOException;
// An example of a very simple socket server. Start by looking at the
// static main() method at the bottom of this file.
public class VerySimpleServer {
private int serverPort = 0;
private ServerSocket serverSock = null;
public VerySimpleServer(int serverPort) {
this.serverPort = serverPort;
try {
serverSock = new ServerSocket(serverPort);
}
catch (IOException e){
e.printStackTrace(System.err);
}
}
// All this method does is wait for some bytes from the
// connection, read them, then write them back again, until the
// socket is closed from the other side.
public void handleConnection(InputStream sockInput, OutputStream sockOutput) {
while(true) {
byte[] buf=new byte[1024];
int bytes_read = 0;
try {
// This call to read() will wait forever, until the
// program on the other side either sends some data,
// or closes the socket.
bytes_read = sockInput.read(buf, 0, buf.length);
// If the socket is closed, sockInput.read() will return -1.
if(bytes_read < 0) {
System.err.println("Tried to read from socket, read() returned < 0, Closing socket.");
return;
}
System.err.println("Received "+bytes_read
+" bytes, sending them back to client, data="
+(new String(buf, 0, bytes_read)));
sockOutput.write(buf, 0, bytes_read);
// This call to flush() is optional - we're saying go
// ahead and send the data now instead of buffering
// it.
sockOutput.flush();
}
catch (Exception e){
System.err.println("Exception reading from/writing to socket, e="+e);
e.printStackTrace(System.err);
return;
}
}
}
public void waitForConnections() {
Socket sock = null;
InputStream sockInput = null;
OutputStream sockOutput = null;
while (true) {
try {
// This method call, accept(), blocks and waits
// (forever if necessary) until some other program
// opens a socket connection to our server. When some
// other program opens a connection to our server,
// accept() creates a new socket to represent that
// connection and returns.
sock = serverSock.accept();
System.err.println("Have accepted new socket.");
// From this point on, no new socket connections can
// be made to our server until we call accept() again.
sockInput = sock.getInputStream();
sockOutput = sock.getOutputStream();
}
catch (IOException e){
e.printStackTrace(System.err);
}
// Do something with the socket - read bytes from the
// socket and write them back to the socket until the
// other side closes the connection.
handleConnection(sockInput, sockOutput);
// Now we close the socket.
try {
System.err.println("Closing socket.");
sock.close();
}
catch (Exception e){
System.err.println("Exception while closing socket.");
e.printStackTrace(System.err);
}
System.err.println("Finished with socket, waiting for next connection.");
}
}
public static void main(String argv[]) {
int port = 54321;
VerySimpleServer server = new VerySimpleServer(port);
server.waitForConnections();
}
}
