怎样使用Java Servlet动态生成图片详解

public class createimageservlet extends httpservlet {　protected void doget(httpservletrequest request, httpservletresponse response)　throws servletexception, ioexception　{　　response.setcontenttype("image/jpeg");　}}

int width = 100;int height = 100;bufferedimage bi = new bufferedimage(width, height, bufferedimage.type_int_rgb);

graphics2d g = bi.creategraphics();// 创建graphics2d对象// 填充背景为白色：g.setbackground(color.blue);g.clearrect(0, 0, width, height);// 设置前景色：g.setcolor(color.red);// 开始绘图：g.drawline(0, 0, 99, 99);// 绘制一条直线// 绘图完成，释放资源：g.dispose();bi.flush();

jpegimageencoder encoder= jpegcodec.createjpegencoder(out);jpegencodeparam param = encoder.getdefaultjpegencodeparam(bi);param.setquality(1.0f, false);encoder.setjpegencodeparam(param);try{　encoder.encode(bi);}catch(ioexception ioe){　ioe.printstacktrace();}

package com.crackj2ee.web.util;import java.io.*;import java.awt.*;import java.awt.image.*;import javax.servlet.*;import javax.servlet.http.*;import com.sun.image.codec.jpeg.*;/*** @author liao xue feng*/public class createimageservlet extends httpservlet{　protected void doget(httpservletrequest request, httpservletresponse response)　throws servletexception,ioexception　{　　response.setcontenttype("image/jpeg");　　createimage(response.getoutputstream());　}　private void createimage(outputstream out){　　int width = 100;　　int height = 100;　　bufferedimage bi = new bufferedimage(width, height, bufferedimage.type_int_rgb);　　graphics2d g = bi.creategraphics();　　// set background:　　g.setbackground(color.blue);　　g.clearrect(0, 0, width, height);　　// set fore color:　　g.setcolor(color.red);　　// start draw:　　g.drawline(0, 0, 99, 199);　　// end draw:　　g.dispose();　　bi.flush();　　// encode:　　jpegimageencoder encoder = jpegcodec.createjpegencoder(out);　　jpegencodeparam param = encoder.getdefaultjpegencodeparam(bi);　　param.setquality(1.0f, false);　　encoder.setjpegencodeparam(param);　　try {　　　encoder.encode(bi);　　}　　catch(ioexception ioe) {　　　ioe.printstacktrace();　　}　}}

＜html＞＜head＞＜/head＞＜body＞＜img src="createimage"＞＜/body＞＜/html＞