A screenshot, screen capture, or screen dump is an image taken by the computer to record the visible items displayed on the monitor or another visual output device. Usually this is a digital image taken by the host operating system or software running on the computer device, but it can also be a capture made by a camera or a device intercepting the video output of the computer.
Screenshots, screen dumps, or screen captures can be used to demonstrate a program, a particular problem a user might be having or generally when computer output needs to be shown to others or archived, or to simply show off what you do on your computer to others. [Wikipedia]
The following java program demonstrates how to use Robot class from java.awt package to capture screenshots and save the image thus captured to disk.
package com.kushal.utils;
/**
* @author Kushal Paudyal
* JavaScreenCaptureUtil.java
*
* This utility captures the screenshot and saves
* the captured image to disk.
*/
import java.awt.Dimension;
import java.awt.Graphics;
import java.awt.Image;
import java.awt.Rectangle;
import java.awt.Robot;
import java.awt.Toolkit;
import java.awt.image.BufferedImage;
import java.io.File;
import java.io.IOException;
import java.text.SimpleDateFormat;
import java.util.Calendar;
import javax.imageio.ImageIO;
public class JavaScreenCaptureUtil {
public static void main(String args[]) throws Exception {
/**
* This class (Robot.java) is used to generate native system input events for the
* purposes of test automation, self-running demos, and other
* applications where control of the mouse and keyboard is needed.
* The primary purpose of Robot is to facilitate automated testing
* of Java platform implementations.
*/
Robot robot = new Robot();
/**
* Get the current screen dimensions.
*/
Dimension d = new Dimension(Toolkit.getDefaultToolkit().getScreenSize());
int width = (int) d.getWidth();
int height = (int) d.getHeight();
/**
* Delay the robot for 5 seconds (5000 ms) allowing you to switch to proper
* screen/window whose screenshot is to be taken.
*
* You can change the delay time as required.
*/
robot.delay(5000);
/**
* Create a screen capture of the active window and then create a buffered image
* to be saved to disk.
*/
Image image = robot.createScreenCapture(new Rectangle(0, 0, width,
height));
BufferedImage bi = new BufferedImage(width, height,
BufferedImage.TYPE_INT_RGB);
Graphics g = bi.createGraphics();
g.drawImage(image, 0, 0, width, height, null);
/**
* Filename where to save the file to.
* I am appending formatted timestamp to the filename.
*/
String fileNameToSaveTo = "C:/temp/screenCapture_"
+ createTimeStampStr() + ".PNG";
/**
* Write the captured image to a file.
* I am using PNG format. You can choose PNG, JPG, GIF.
*/
writeImage(bi, fileNameToSaveTo, "PNG");
System.out.println("Screen Captured Successfully and Saved to:n"+fileNameToSaveTo);
}
/**
* This method writes a buffered image to a file
*
* @param img -- > BufferedImage
* @param fileLocation --> e.g. "C:/testImage.jpg"
* @param extension --> e.g. "jpg","gif","png"
*/
public static void writeImage(BufferedImage img, String fileLocation,
String extension) {
try {
BufferedImage bi = img;
File outputfile = new File(fileLocation);
ImageIO.write(bi, extension, outputfile);
} catch (IOException e) {
e.printStackTrace();
}
}
/**
*
* @return String representation of timestamp
* in the format of yyyyMMdd_hhmmss (e.g. 20100426_111612)
* @throws Exception
*/
public static String createTimeStampStr() throws Exception {
Calendar mycalendar = Calendar.getInstance();
SimpleDateFormat formatter = new SimpleDateFormat("yyyyMMdd_hhmmss");
String timeStamp = formatter.format(mycalendar.getTime());
return timeStamp;
}
/*
* SANJAAL CORPS MAKES NO REPRESENTATIONS OR WARRANTIES ABOUT THE
* SUITABILITY OF THE SOFTWARE, EITHER EXPRESS OR IMPLIED, INCLUDING BUT NOT
* LIMITED TO THE IMPLIED WARRANTIES OF MERCHANTABILITY, FITNESS FOR A
* PARTICULAR PURPOSE, OR NON-INFRINGEMENT. SANJAAL CORPS SHALL NOT BE
* LIABLE FOR ANY DAMAGES SUFFERED BY LICENSEE AS A RESULT OF USING,
* MODIFYING OR DISTRIBUTING THIS SOFTWARE OR ITS DERIVATIVES.
*
* THIS SOFTWARE IS NOT DESIGNED OR INTENDED FOR USE OR RESALE AS ON-LINE
* CONTROL EQUIPMENT IN HAZARDOUS ENVIRONMENTS REQUIRING FAIL-SAFE
* PERFORMANCE, SUCH AS IN THE OPERATION OF NUCLEAR FACILITIES, AIRCRAFT
* NAVIGATION OR COMMUNICATION SYSTEMS, AIR TRAFFIC CONTROL, DIRECT LIFE
* SUPPORT MACHINES, OR WEAPONS SYSTEMS, IN WHICH THE FAILURE OF THE
* SOFTWARE COULD LEAD DIRECTLY TO DEATH, PERSONAL INJURY, OR SEVERE
* PHYSICAL OR ENVIRONMENTAL DAMAGE ("HIGH RISK ACTIVITIES"). SANJAAL CORPS
* SPECIFICALLY DISCLAIMS ANY EXPRESS OR IMPLIED WARRANTY OF FITNESS FOR
* HIGH RISK ACTIVITIES.
*/
}
