java实现的图片裁剪功能示例

package Tsets;
import java.awt.Rectangle;
import java.awt.image.BufferedImage;
import java.io.File;
import java.io.FileInputStream;
import java.io.IOException;
import java.util.Iterator;
import javax.imageio.ImageIO;
import javax.imageio.ImageReadParam;
import javax.imageio.ImageReader;
import javax.imageio.stream.ImageInputStream;
public class PicCut {
  public void cut(int x,int y,int width,int height,String srcpath,String subpath) throws IOException {//裁剪方法
    FileInputStream is = null;
    ImageInputStream iis = null;
    try {
      is = new FileInputStream(srcpath); //读取原始图片
      Iterator it = ImageIO.getImageReadersByFormatName("jpg"); //ImageReader声称能够解码指定格式
      ImageReader reader = it.next();
      iis = ImageIO.createImageInputStream(is); //获取图片流
      reader.setInput(iis, true); //将iis标记为true（只向前搜索）意味着包含在输入源中的图像将只按顺序读取
      ImageReadParam param = reader.getDefaultReadParam(); //指定如何在输入时从 Java Image I/O框架的上下文中的流转换一幅图像或一组图像
      Rectangle rect = new Rectangle(x, y, width, height); //定义空间中的一个区域
      param.setSourceRegion(rect); //提供一个 BufferedImage，将其用作解码像素数据的目标。
      BufferedImage bi = reader.read(0, param); //读取索引imageIndex指定的对象
      ImageIO.write(bi, "jpg", new File(subpath)); //保存新图片
    } finally {
      if (is != null)
        is.close();
      if (iis != null)
        iis.close();
    }
  }
  public static void main(String[] args) throws Exception {
      PicCut pc = new PicCut();
    pc.cut(20, 20, 100, 100,"D:\\1.jpg","D:\\11.jpg");
    System.out.println("ok");
  }
}