Est-il possible de prendre une capture d'écran à l'aide de Java et de l'enregistrer sur une sorte d'image?

Croyez le ou pas, vous pouvez réellement utiliser java.awt.Robot à "créer une image contenant des pixels lire à l'écran." Vous pouvez ensuite graver cette image sur un fichier sur le disque.

Je l'ai juste essayé, et le tout se termine comme:

Rectangle screenRect = new Rectangle(Toolkit.getDefaultToolkit().getScreenSize());
BufferedImage capture = new Robot().createScreenCapture(screenRect);
ImageIO.write(capture, "bmp", new File(args[0]));

REMARQUE: Cela ne fera que la capture de l'écran principal. Voir GraphicsConfiguration pour le support multi-moniteur.

Si vous souhaitez capturer tous les moniteurs, vous pouvez utiliser le code suivant:

GraphicsEnvironment ge = GraphicsEnvironment.getLocalGraphicsEnvironment();
GraphicsDevice[] screens = ge.getScreenDevices();

Rectangle allScreenBounds = new Rectangle();
for (GraphicsDevice screen : screens) {
    Rectangle screenBounds = screen.getDefaultConfiguration().getBounds();

    allScreenBounds.width += screenBounds.width;
    allScreenBounds.height = Math.max(allScreenBounds.height, screenBounds.height);
}

Robot robot = new Robot();
BufferedImage screenShot = robot.createScreenCapture(allScreenBounds);

import java.awt.Color;
import java.awt.Dimension;
import java.awt.Rectangle;
import java.awt.Robot;
import java.awt.Toolkit;
import java.awt.event.ActionEvent;
import java.awt.event.ActionListener;
import java.awt.image.BufferedImage;
import java.io.File; 
import javax.imageio.ImageIO;
import javax.swing.*;  
public class HelloWorldFrame extends JFrame implements ActionListener {
JButton b;
public HelloWorldFrame() {
this.setVisible(true);
this.setLayout(null);
b = new JButton("Click Here");
b.setBounds(380, 290, 120, 60);
b.setBackground(Color.red);
b.setVisible(true);
b.addActionListener(this);
add(b);
setSize(1000, 700);
}
public void actionPerformed(ActionEvent e)
{
if (e.getSource() == b) 
{
this.dispose();
try {
Thread.sleep(1000);
Toolkit tk = Toolkit.getDefaultToolkit(); 
Dimension d = tk.getScreenSize();
Rectangle rec = new Rectangle(0, 0, d.width, d.height);  
Robot ro = new Robot();
BufferedImage img = ro.createScreenCapture(rec);
File f = new File("myimage.jpg");//set appropriate path
ImageIO.write(img, "jpg", f);
} catch (Exception ex) {
System.out.println(ex.getMessage());
}
}
}
public static void main(String[] args) {
HelloWorldFrame obj = new HelloWorldFrame();
}
}

Vous pouvez utiliser java.awt.Robot pour réaliser cette tâche.

ci-dessous est le code du serveur, ce qui économise de la phase de capture de l'image dans votre Répertoire.

import java.awt.image.BufferedImage;
import java.io.File;
import java.io.IOException;
import java.net.ServerSocket;
import java.net.Socket;
import java.net.SocketTimeoutException;
import java.sql.SQLException;
import java.text.DateFormat;
import java.text.SimpleDateFormat;
import java.util.Date;
import javax.imageio.ImageIO;
public class ServerApp extends Thread
{
private ServerSocket serverSocket=null;
private static Socket server = null;
private Date date = null;
private static final String DIR_NAME = "screenshots";
public ServerApp() throws IOException, ClassNotFoundException, Exception{
serverSocket = new ServerSocket(61000);
serverSocket.setSoTimeout(180000);
}
public void run()
{
while(true)
{
try
{
server = serverSocket.accept();
date = new Date();
DateFormat dateFormat = new SimpleDateFormat("_yyMMdd_HHmmss");
String fileName = server.getInetAddress().getHostName().replace(".", "-");
System.out.println(fileName);
BufferedImage img=ImageIO.read(ImageIO.createImageInputStream(server.getInputStream()));
ImageIO.write(img, "png", new File("D:\\screenshots\\"+fileName+dateFormat.format(date)+".png"));
System.out.println("Image received!!!!");
//lblimg.setIcon(img);
}
catch(SocketTimeoutException st)
{
System.out.println("Socket timed out!"+st.toString());
//createLogFile("[stocktimeoutexception]"+stExp.getMessage());
break;
}
catch(IOException e)
{
e.printStackTrace();
break;
}
catch(Exception ex)
{
System.out.println(ex);
}
}
}
public static void main(String [] args) throws IOException, SQLException, ClassNotFoundException, Exception{
ServerApp serverApp = new ServerApp();
serverApp.createDirectory(DIR_NAME);
Thread thread = new Thread(serverApp);
thread.start();
}
private void createDirectory(String dirName) {
File newDir = new File("D:\\"+dirName);
if(!newDir.exists()){
boolean isCreated = newDir.mkdir();
}
}
} 

Et c'est le code Client qui est en cours d'exécution sur le fil et quelques minutes après, il est de capturer la capture d'écran de l'écran utilisateur.

package com.viremp.client;
import java.awt.AWTException;
import java.awt.Dimension;
import java.awt.Rectangle;
import java.awt.Robot;
import java.awt.Toolkit;
import java.awt.image.BufferedImage;
import java.io.IOException;
import java.net.Socket;
import java.util.Random;
import javax.imageio.ImageIO;
public class ClientApp implements Runnable {
private static long nextTime = 0;
private static ClientApp clientApp = null;
private String serverName = "192.168.100.18"; //loop back ip
private int portNo = 61000;
//private Socket serverSocket = null;
/**
* @param args
* @throws InterruptedException 
*/
public static void main(String[] args) throws InterruptedException {
clientApp = new ClientApp();
clientApp.getNextFreq();
Thread thread = new Thread(clientApp);
thread.start();
}
private void getNextFreq() {
long currentTime = System.currentTimeMillis();
Random random = new Random();
long value = random.nextInt(180000); //1800000
nextTime = currentTime + value;
//return currentTime+value;
}
@Override
public void run() {
while(true){
if(nextTime < System.currentTimeMillis()){
System.out.println(" get screen shot ");
try {
clientApp.sendScreen();
clientApp.getNextFreq();
} catch (AWTException e) {
//TODO Auto-generated catch block
System.out.println(" err"+e);
} catch (IOException e) {
//TODO Auto-generated catch block
e.printStackTrace();
} catch(Exception e){
e.printStackTrace();
}
}
//System.out.println(" statrted ....");
}
}
private void sendScreen()throws AWTException, IOException {
Socket serverSocket = new Socket(serverName, portNo);
Toolkit toolkit = Toolkit.getDefaultToolkit();
Dimension dimensions = toolkit.getScreenSize();
Robot robot = new Robot();  //Robot class 
BufferedImage screenshot = robot.createScreenCapture(new Rectangle(dimensions));
ImageIO.write(screenshot,"png",serverSocket.getOutputStream());
serverSocket.close();
}
}