JNA 调用windows平台截取屏幕

import java.awt.Dimension;import java.awt.Rectangle;import java.awt.Toolkit;import java.awt.image.BufferedImage;import java.awt.image.ColorModel;import java.awt.image.DataBuffer;import java.awt.image.DataBufferInt;import java.awt.image.DataBufferUShort;import java.awt.image.DirectColorModel;import java.awt.image.Raster;import java.awt.image.WritableRaster;import java.io.File;import java.io.IOException;import javax.imageio.ImageIO;import com.sun.jna.Native;import com.sun.jna.platform.win32.WinDef.HBITMAP;import com.sun.jna.platform.win32.WinDef.HDC;import com.sun.jna.platform.win32.WinDef.HWND;import com.sun.jna.platform.win32.WinGDI;import com.sun.jna.platform.win32.WinGDI.BITMAPINFO;import com.sun.jna.platform.win32.WinGDI.BITMAPINFOHEADER;import com.sun.jna.platform.win32.WinNT.HANDLE;import com.sun.jna.win32.W32APIOptions;public class JNAScreenShot {public static void main(String[] args) {// 获取屏幕尺寸Dimension d = Toolkit.getDefaultToolkit().getScreenSize();BufferedImage screenshot = getScreenshot(new Rectangle(0, 0, 4352, 64));// 写入文件try {ImageIO.write(screenshot, "jpg", new File("D://123.jpg"));System.out.println("截屏成功！");} catch (IOException e) {// TODO Auto-generated catch blocke.printStackTrace();}}public static BufferedImage getScreenshot(Rectangle bounds) {HDC windowDC = GDI.GetDC(USER.GetDesktopWindow());HBITMAP outputBitmap = GDI.CreateCompatibleBitmap(windowDC,bounds.width, bounds.height);try {HDC blitDC = GDI.CreateCompatibleDC(windowDC);try {HANDLE oldBitmap = GDI.SelectObject(blitDC, outputBitmap);try {GDI.BitBlt(blitDC, 0, 0, bounds.width, bounds.height,windowDC, bounds.x, bounds.y, GDI32.SRCCOPY);} finally {GDI.SelectObject(blitDC, oldBitmap);}BITMAPINFO bi = new BITMAPINFO(40);bi.bmiHeader.biSize = 40;boolean ok = GDI.GetDIBits(blitDC, outputBitmap, 0, bounds.height,(byte[]) null, bi, WinGDI.DIB_RGB_COLORS);if (ok) {BITMAPINFOHEADER bih = bi.bmiHeader;bih.biHeight = -Math.abs(bih.biHeight);bi.bmiHeader.biCompression = 0;return bufferedImageFromBitmap(blitDC, outputBitmap, bi);} else {return null;}} finally {GDI.DeleteObject(blitDC);}} finally {GDI.DeleteObject(outputBitmap);}}private static BufferedImage bufferedImageFromBitmap(HDC blitDC,HBITMAP outputBitmap, BITMAPINFO bi) {BITMAPINFOHEADER bih = bi.bmiHeader;int height = Math.abs(bih.biHeight);final ColorModel cm;final DataBuffer buffer;final WritableRaster raster;int strideBits = (bih.biWidth * bih.biBitCount);int strideBytesAligned = (((strideBits - 1) | 0x1F) + 1) >> 3;final int strideElementsAligned;switch (bih.biBitCount) {case 16:strideElementsAligned = strideBytesAligned / 2;cm = new DirectColorModel(16, 0x7C00, 0x3E0, 0x1F);buffer = new DataBufferUShort(strideElementsAligned * height);raster = Raster.createPackedRaster(buffer, bih.biWidth, height,strideElementsAligned, ((DirectColorModel) cm).getMasks(),null);break;case 32:strideElementsAligned = strideBytesAligned / 4;cm = new DirectColorModel(32, 0xFF0000, 0xFF00, 0xFF);buffer = new DataBufferInt(strideElementsAligned * height);raster = Raster.createPackedRaster(buffer, bih.biWidth, height,strideElementsAligned, ((DirectColorModel) cm).getMasks(),null);break;default:throw new IllegalArgumentException("Unsupported bit count: "+ bih.biBitCount);}final boolean ok;switch (buffer.getDataType()) {case DataBuffer.TYPE_INT: {int[] pixels = ((DataBufferInt) buffer).getData();ok = GDI.GetDIBits(blitDC, outputBitmap, 0, raster.getHeight(),pixels, bi, 0);}break;case DataBuffer.TYPE_USHORT: {short[] pixels = ((DataBufferUShort) buffer).getData();ok = GDI.GetDIBits(blitDC, outputBitmap, 0, raster.getHeight(),pixels, bi, 0);}break;default:throw new AssertionError("Unexpected buffer element type: "+ buffer.getDataType());}if (ok) {return new BufferedImage(cm, raster, false, null);} else {return null;}}private static final User32 USER = User32.INSTANCE;private static final GDI32 GDI = GDI32.INSTANCE;}interface GDI32 extends com.sun.jna.platform.win32.GDI32 {GDI32 INSTANCE = (GDI32) Native.loadLibrary(GDI32.class);boolean BitBlt(HDC hdcDest, int nXDest, int nYDest, int nWidth,int nHeight, HDC hdcSrc, int nXSrc, int nYSrc, int dwRop);HDC GetDC(HWND hWnd);boolean GetDIBits(HDC dc, HBITMAP bmp, int startScan, int scanLines,byte[] pixels, BITMAPINFO bi, int usage);boolean GetDIBits(HDC dc, HBITMAP bmp, int startScan, int scanLines,short[] pixels, BITMAPINFO bi, int usage);boolean GetDIBits(HDC dc, HBITMAP bmp, int startScan, int scanLines,int[] pixels, BITMAPINFO bi, int usage);int SRCCOPY = 0xCC0020;}interface User32 extends com.sun.jna.platform.win32.User32 {User32 INSTANCE = (User32) Native.loadLibrary(User32.class,W32APIOptions.UNICODE_OPTIONS);HWND GetDesktopWindow();}