showimage.java

一个用java开发的网上购物系统。基本功能都是可以实现的

package store;
import java.io.*;
import java.util.*;
import javax.servlet.*;
import javax.servlet.http.*;
import com.sun.image.codec.jpeg.*;
import java.awt.image.*;
import java.awt.*;
import javax.imageio.ImageIO;

public class ShowImage extends HttpServlet {
    private int old_w=0;  //定义原图片宽
    private int old_h=0;  //定义原图片高
    private int new_w=80;  //定义新图长
    private int new_h=90;
    //private float imagesize;
    public void doGet(HttpServletRequest request,
                      HttpServletResponse response)
        throws IOException, ServletException
    {
        response.setContentType("image/jpeg;charset=GBK");
        try{
           String pp=request.getParameter("path");
           String path="D:/Tomcat 5.5/webapps/Store/pimage/"+pp;
           File file = new File(path);

           Image src =ImageIO.read(file);    //构造Image对象

           old_w=src.getWidth(null);    //得到原图片宽度
           old_h=src.getHeight(null);    //得到原图片高度

           //new_w=Math.round(old_w*imagesize); //计算新图宽宽
           //new_h=Math.round(old_h*imagesize); //计算新图高宽
           BufferedImage image = new BufferedImage(new_w,new_h,BufferedImage.TYPE_INT_RGB);
           //重新绘出缩小后的图
           image.getGraphics().drawImage(src,0,0,new_w,new_h,null);
          //获取输出流
         ServletOutputStream newimage=response.getOutputStream();
         JPEGImageEncoder encoder = JPEGCodec.createJPEGEncoder(newimage);
         encoder.encode(image);    //JPEG编码
         newimage.close();
       }
       catch(Exception e)
          {
            PrintWriter out = response.getWriter();
            out.print(e.toString());
          }

    }
    public void doPost(HttpServletRequest request,
                      HttpServletResponse response)
        throws IOException, ServletException
    {
      doGet(request,response);
    }
   public void destroy()
    {

    }
}