用java处理图片（压缩成小尺寸；加文字和logo水印）

/***功能：压缩图片变成小尺寸***
*参数1：oImage：原图；*
*参数2：maxWidth：小尺寸宽度；*
*参数3：maxHeight：小尺寸长度；*
*参数4：newImageName：小尺寸图片存放的路径和新名字；*
*参数5：fileType：小尺寸图片类型（png,gif,jpg...）***/
private void compressImage(File oImage, int maxWidth, int maxHeight, String newImageName, String fileType) {
BufferedImage srcImage = ImageIO.read(oImage);;
int srcWidth = srcImage.getWidth(null);
int srcHeight = srcImage.getHeight(null);
if(srcWidth <= maxWidth && srcHeight <= maxHeight){
saveImage(srcImage);
return;
}
Image scaledImage = srcImage.getScaledInstance(srcWidth, srcHeight, Image.SCALE_SMOOTH);
double ratio = Math.min((double) maxWidth / srcWidth, (double) maxHeight / srcHeight);
AffineTransformOp op = new AffineTransformOp(AffineTransform.getScaleInstance(ratio, ratio), null);
scaledImage = op.filter(srcImage, null);
saveImage((BufferedImage)scaledImage, fileType, new FileOutputStream(newImageName));// 存盘
}

/***功能：图片加文字水印***
*参数1：oImage：原图；*
*参数2：newImageName：加文字水印图片存放的路径和新名字；*
*参数3：fileType：加文字水印图片类型（png,gif,jpg...）；
*参数4：waterText：文字水印的内容****/
private boolean pressText(File oImage, String newImageName, String fileType, String waterText) throws IOException{
BufferedImage originalImage = ImageIO.read(oImage);
int originalWidth = originalImage.getWidth(null);
int originalHeight = originalImage.getHeight(null);
if (originalWidth < 50 || originalHeight < 50){
return false;
}
if(waterText==null || waterText.trim().equals("")){
return false;
}
BufferedImage newImage = new BufferedImage(originalWidth, originalHeight, BufferedImage.TYPE_INT_RGB);
Graphics2D g = newImage.createGraphics();
g.drawImage(originalImage, 0, 0, originalWidth, originalHeight, null);
g.setColor(Color.RED);
int fontSize = 13;
g.setFont(new Font("宋体", Font.PLAIN, fontSize));
g.setComposite(AlphaComposite.getInstance(AlphaComposite.SRC_ATOP, 0.5f));
int len = InitServlet.WATER_TEXT.length();
if(InitServlet.IS_WATER_CENTER==0){
g.drawString(InitServlet.WATER_TEXT, originalWidth-len*fontSize/2-6,originalHeight-6);
}else{
g.drawString(InitServlet.WATER_TEXT, (originalWidth-(len*fontSize))/2, (originalHeight-fontSize)/2);
}
g.dispose();
ImageIO.write(newImage, fileType, new FileOutputStream(newImageName));// 存盘
return true;
}

/***功能：图片加logo图片水印***
*参数1：oImage：原图；*
*参数2：newImageName：加logo图片水印存放的路径和新名字；*
*参数3：fileType：加logo图片水印图片类型（png,gif,jpg...）；
*参数4：logoPath：logo水印图片的存放路径****/
private boolean pressImage(File oImage, String newImageName, String fileType, String logoPath) throws IOException{
File waterMarkImage = new File(logoPath);
if (!waterMarkImage.exists()) {
return false;
}
BufferedImage originalImage = ImageIO.read(oImage);
BufferedImage watermarkImage = ImageIO.read(waterMarkImage);
int originalWidth = originalImage.getWidth(null);
int originalHeight = originalImage.getHeight(null);
int watermarkWidth = watermarkImage.getWidth(null);
int watermarkHeight = watermarkImage.getHeight(null);
if (originalWidth <= watermarkWidth || originalHeight <= watermarkHeight || originalWidth < 50 || originalHeight < 50) {
return false;
}
BufferedImage newImage = new BufferedImage(originalWidth, originalHeight, BufferedImage.TYPE_INT_RGB);
Graphics2D g = newImage.createGraphics();
g.drawImage(originalImage, 0, 0, originalWidth, originalHeight, null);
g.setComposite(AlphaComposite.getInstance(AlphaComposite.SRC_ATOP, 0.5f));
if(InitServlet.IS_WATER_CENTER==0){
g.drawImage(watermarkImage, originalWidth-watermarkWidth-10, originalHeight-watermarkHeight-10, watermarkWidth, watermarkHeight, null);
}else{
g.drawImage(watermarkImage, (originalWidth-watermarkWidth)/2, (originalHeight-watermarkHeight)/2, watermarkWidth, watermarkHeight, null);
}
g.dispose();
ImageIO.write(newImage, fileType, new FileOutputStream(newImageName));// 存盘
return true;
}