1：//獲取當前方法的名稱
String methodName = Thread.currentThread().getStackTrace()[1].getMethodName();
2：字符串和整形數據之間 的想換轉換
String a = String.valueOf(2);
int i = Integer.parseInt(a);
3：文件末尾添加數據內容
BufferedWriter out =
null; try
{ out =
new BufferedWriter(new
FileWriter(”filename”, true));
out.write(”aString”);
} catch
(IOException e) { // error processing code
} finally
{ if
(out != null) {
out.close();
}
}4：使用NIO快速拷貝文件public
static void fileCopy( File in, File out )
throws
IOException {
FileChannel inChannel =
new FileInputStream( in ).getChannel();
FileChannel outChannel =
new FileOutputStream( out ).getChannel();
try {
// inChannel.transferTo(0, inChannel.size(), outChannel); // original -- apparently has trouble copying large files on Windows
// magic number for Windows, 64Mb - 32Kb)
int
maxCount = (64
* 1024 * 1024) - (32
* 1024);
long
size = inChannel.size(); long
position = 0;
while
( position < size ) {
position += inChannel.transferTo( position, maxCount, outChannel );
}
}
finally {
if
( inChannel != null
) {
inChannel.close();
}
if
( outChannel != null
) {
outChannel.close();
}
}
}5：創建圖片縮略圖private
void createThumbnail(String filename, int
thumbWidth, int
thumbHeight, int
quality, String outFilename) throws
InterruptedException, FileNotFoundException, IOException
{
// load image from filename
Image image = Toolkit.getDefaultToolkit().getImage(filename);
MediaTracker mediaTracker =
new MediaTracker(new
Container()); mediaTracker.addImage(image,
0); mediaTracker.waitForID(0);
// use this to test for errors at this point: System.out.println(mediaTracker.isErrorAny());
// determine thumbnail size from WIDTH and HEIGHT
double
thumbRatio = (double)thumbWidth / (double)thumbHeight;
int
imageWidth = image.getWidth(null);
int
imageHeight = image.getHeight(null);
double
imageRatio = (double)imageWidth / (double)imageHeight;
if
(thumbRatio < imageRatio) { thumbHeight = (int)(thumbWidth / imageRatio);
}
else { thumbWidth = (int)(thumbHeight * imageRatio);
}
// draw original image to thumbnail image object and
// scale it to the new size on-the-fly
BufferedImage thumbImage =
new BufferedImage(thumbWidth, thumbHeight, BufferedImage.TYPE_INT_RGB);
Graphics2D graphics2D = thumbImage.createGraphics();
graphics2D.setRenderingHint(RenderingHints.KEY_INTERPOLATION, RenderingHints.VALUE_INTERPOLATION_BILINEAR);
graphics2D.drawImage(image,
0, 0, thumbWidth, thumbHeight,
null); // save thumbnail image to outFilename
BufferedOutputStream out =
new BufferedOutputStream(new
FileOutputStream(outFilename)); JPEGImageEncoder encoder = JPEGCodec.createJPEGEncoder(out);
JPEGEncodeParam param = encoder.getDefaultJPEGEncodeParam(thumbImage);
quality = Math.max(0, Math.min(quality,
100)); param.setQuality((float)quality /
100.0f, false);
encoder.setJPEGEncodeParam(param);
encoder.encode(thumbImage);
out.close();
}