com.sun.image.codec.jpeg.*在jdk里面的jre,找到rt.jar
Java代码
- import java.io.IOException;
- import javax.servlet.ServletException;
- import javax.servlet.http.HttpServletRequest;
- import javax.servlet.http.HttpServletResponse;
- import java.io.*;
- import javax.servlet.*;
- import javax.servlet.http.*;
- import com.sun.image.codec.jpeg.*;//sun公司仅提供了jpg图片文件的编码api
- import javax.imageio.stream.*;
- import java.awt.*;
- import java.awt.image.BufferedImage;
- /**
- *
- * 显示文件的Servlet
- * 负责从本地文件中读取图片,
- *
- */
- public class ShowPic extends javax.servlet.http.HttpServlet implements
- javax.servlet.Servlet {
- private static final String GIF = "image/gif;charset=GB2312";// 设定输出的类型
- private static final String JPG = "image/jpeg;charset=GB2312";
- /*
- * (non-Java-doc)
- *
- * @see javax.servlet.http.HttpServlet#HttpServlet()
- */
- public ShowPic() {
- super();
- }
- /*
- * (non-Java-doc)
- *
- * @see javax.servlet.http.HttpServlet#doGet(HttpServletRequest request,
- * HttpServletResponse response)
- */
- protected void doGet(HttpServletRequest request,
- HttpServletResponse response) throws ServletException, IOException {
- doPost(request, response);
- }
- /*
- * (non-Java-doc)
- *
- * @see javax.servlet.http.HttpServlet#doPost(HttpServletRequest request,
- * HttpServletResponse response)
- */
- protected void doPost(HttpServletRequest request,
- HttpServletResponse response) throws ServletException, IOException {
- String spec = request.getParameter("spec");// 输出图片的类型的标志
- String imagePath = "D:\\temp\\1.jpg";
- response.reset();
- OutputStream output = response.getOutputStream();// 得到输出流
- if (imagePath.toLowerCase().endsWith(".jpg"))// 使用编码处理文件流的情况:
- {
- response.setContentType(JPG);// 设定输出的类型
- // 得到图片的真实路径
- // 得到图片的文件流
- InputStream imageIn = new FileInputStream(new File(imagePath));
- // 得到输入的编码器,将文件流进行jpg格式编码
- JPEGImageDecoder decoder = JPEGCodec.createJPEGDecoder(imageIn);
- // 得到编码后的图片对象
- BufferedImage image = decoder.decodeAsBufferedImage();
- // 得到输出的编码器
- JPEGImageEncoder encoder = JPEGCodec.createJPEGEncoder(output);
- encoder.encode(image);// 对图片进行输出编码
- imageIn.close();// 关闭文件流
- }
- if (imagePath.toLowerCase().endsWith(".gif"))// 不使用编码处理文件流的情况:
- {
- response.setContentType(GIF);
- ServletContext context = getServletContext();// 得到背景对象
- InputStream imageIn = context.getResourceAsStream(imagePath);// 文件流
- BufferedInputStream bis = new BufferedInputStream(imageIn);// 输入缓冲流
- BufferedOutputStream bos = new BufferedOutputStream(output);// 输出缓冲流
- byte data[] = new byte[4096];// 缓冲字节数
- int size = 0;
- size = bis.read(data);
- while (size != -1) {
- bos.write(data, 0, size);
- size = bis.read(data);
- }
- bis.close();
- bos.flush();// 清空输出缓冲流
- bos.close();
- }
- output.close();
- }
- }
想要调用的话,你可以简单的映射一下servelt,我就将servet的名映射为
Html代码
- <servlet>
- <servlet-name>ShowPic</servlet-name>
- <display-name>ShowPic</display-name>
- <description></description>
- <servlet-class>
- cn.ccb.zlgz.web.servlet.ShowPic</servlet-class>
- </servlet>
- <servlet-mapping>
- <servlet-name>ShowPic</servlet-name>
- <url-pattern>/ShowPic</url-pattern>
- </servlet-mapping>
使用HTML调用:
Html代码
- <html>
- <body>
- <img src="ShowPic?spec=2"></a>
- </body>
- </html>
时间: 2024-10-12 09:37:13