第一步：读入文件

public BufferedImage loadImageLocal(String path) {

try {

return ImageIO.read(new File(path));

} catch (IOException e) {

e.printStackTrace();

}

return null;

}

第二步：缩放文件

/**

*

* @param mini 贴图

* @param Scale 缩放比例

* @return

*/

public BufferedImage modifyImageScale(BufferedImage mini,double Scale) {

int w = (int)Math.round(mini.getWidth()*Scale);

int h = (int)Math.round(mini.getHeight()*Scale);

//设置生成图片宽*高，色彩

BufferedImage bi = new BufferedImage(w, h, BufferedImage.TYPE_INT_RGB);

//创建画布

Graphics2D g2 = bi.createGraphics()；

//设置图片透明 注********：只有png格式的图片才能设置背景透明，jpg设置图片颜色变的乱七八糟

bi = g2.getDeviceConfiguration().createCompatibleImage(w, h, Transparency.TRANSLUCENT);

//重新创建画布

g2 = bi.createGraphics();

//画图

g2.drawImage(mini, 0,0,w,h, null);

//关闭资源

g2.dispose();

return bi;

}

第三步：旋转文件

/**

*

* @param mini 贴图

* @param ratio 旋转角度

* @return

*/

public BufferedImage modifyImageRatio(BufferedImage mini,int ratio) {

int src_width = mini.getWidth();

int src_height = mini.getHeight();

//针对图片旋转重新计算图的宽*高

Rectangle rect_des = CalcRotatedSize(new Rectangle(new Dimension(

src_width, src_height)), ratio);

//设置生成图片的宽*高，色彩度

BufferedImage res = new BufferedImage(rect_des.width, rect_des.height,BufferedImage.TYPE_INT_RGB);

//创建画布

Graphics2D g2 = res.createGraphics();

res = g2.getDeviceConfiguration().createCompatibleImage(rect_des.width, rect_des.height, Transparency.TRANSLUCENT);

g2 = res.createGraphics();

//重新设定原点坐标

g2.translate((rect_des.width - src_width) / 2,

(rect_des.height - src_height) / 2);

//执行图片旋转，rotate里包含了translate，并还原了原点坐标

g2.rotate(Math.toRadians(ratio), src_width / 2, src_height / 2);

g2.drawImage(mini, null, null);

g2.dispose();

return res;

}

private Rectangle CalcRotatedSize(Rectangle src, int angel) {

if (angel >= 90) {

if(angel / 90 % 2 == 1){

int temp = src.height;

src.height = src.width;

src.width = temp;

}

angel = angel % 90;

}

double r = Math.sqrt(src.height * src.height + src.width * src.width) / 2;

double len = 2 * Math.sin(Math.toRadians(angel) / 2) * r;

double angel_alpha = (Math.PI - Math.toRadians(angel)) / 2;

double angel_dalta_width = Math.atan((double) src.height / src.width);

double angel_dalta_height = Math.atan((double) src.width / src.height);

int len_dalta_width = (int) (len * Math.cos(Math.PI - angel_alpha

- angel_dalta_width));

int len_dalta_height = (int) (len * Math.cos(Math.PI - angel_alpha

- angel_dalta_height));

int des_width = src.width + len_dalta_width * 2;

int des_height = src.height + len_dalta_height * 2;

return new Rectangle(new Dimension(des_width, des_height));

}

第四步：合成文件

/**

*

* @param mini 贴图

* @param big 底图

* @param indexX x坐标位置

* @param indexY y坐标位置

* @return

*/

public BufferedImage modifyImagetogeter(BufferedImage mini, BufferedImage big,Integer indexX,Integer indexY) {

try {

int w =mini.getWidth();

int h =mini.getHeight();

System.out.println(w+" , "+h);

Graphics2D g = big.createGraphics();

g.drawImage(mini, indexX, indexY, w,h, null);

g.dispose();

} catch (Exception e) {

System.out.println(e.getMessage());

}

return big;

}

第五步：导出文件

public void writeImageLocal(String newPath, BufferedImage newImg) {

if (newPath != null && newImg != null) {

try {

File outputfile = new File(newPath);

ImageIO.write(newImg, "png", outputfile);

} catch (IOException e) {

System.out.println(e.getMessage());

}

}

}