JSP、Servlet中的相对路径和绝对路径

网络整理 - 07-27

用servlet将jsp文件内容转为html。代码如下：

package examples;
import java.io.ByteArrayOutputStream;
import java.io.FileOutputStream;
import java.io.IOException;
import java.io.OutputStreamWriter;
import java.io.PrintWriter;

import javax.servlet.RequestDispatcher;
import javax.servlet.ServletContext;
import javax.servlet.ServletException;
import javax.servlet.ServletOutputStream;
import javax.servlet.http.HttpServlet;
import javax.servlet.http.HttpServletRequest;
import javax.servlet.http.HttpServletResponse;
import javax.servlet.http.HttpServletResponseWrapper;

public class ToHtml extends HttpServlet {
private static final String CONTENT_TYPE = "text/html; charset=GBK";
// Initialize global variables
public void init() throws ServletException {
}

// Process the HTTP Get request
public void doGet(HttpServletRequest request, HttpServletResponse response)
   throws ServletException, IOException {
      response.setContentType(CONTENT_TYPE);
      service(request, response);
/**
   * 只有成功初始化后此方法才能被调用处理用户请求。前一个参数提供访问初始请求数据的方法和字段，
   * 后一个提供servlet构造响应的方法。
   */
}
// Process the HTTP Post request
public void doPost(HttpServletRequest request, HttpServletResponse response)
   throws ServletException, IOException {
doGet(request, response);
}
public void destroy() {
}
public void service(HttpServletRequest request, HttpServletResponse response)
   throws ServletException, IOException {

ServletContext sc = getServletContext();
String url = "/index.jsp";

String name = "index.htm"; // 这是生成的html文件名

String pName = "e:\\Tomcat 5.5\\webapps\\jspTohtml\\index.htm"; // 生成html的完整路径
RequestDispatcher rd = sc.getRequestDispatcher(url);
final ByteArrayOutputStream os = new ByteArrayOutputStream();
final ServletOutputStream stream = new ServletOutputStream() {
   public void write(byte[] data, int offset, int length) {
    os.write(data, offset, length);
   }
   public void write(int b) throws IOException {
    os.write(b);
   }
};
final PrintWriter pw = new PrintWriter(new OutputStreamWriter(os));
HttpServletResponse rep = new HttpServletResponseWrapper(response) {
   public ServletOutputStream getOutputStream() {
    return stream;
   }
   public PrintWriter getWriter() {
    return pw;
   }
};
rd.include(request, rep);
pw.flush();
FileOutputStream fos = new FileOutputStream(pName); // 把jsp输出的内容写到指定路径的htm文件中
os.writeTo(fos);
fos.close();
response.sendRedirect(name); // 书写完毕后转向htm页面
}
}

在web.xml文件中配置：

< servlet> < servlet-name>Tohtml< /servlet-name> < servlet-class>examples.ToHtml< /servlet-class>< /servlet> < servlet-mapping> < servlet-name>Tohtml< /servlet-name> < url-pattern>/Tohtml< /url-pattern> < /servlet-mapping>

下面是用来测试的index.jsp:

< %@ page contentType="text/html; charset=gb2312" %>< html> < head> < title>Cache Filter Test< /title> < meta http-equiv="Content-Type" content="text/html; charset=gb2312"> < /head> < body>简单测试:s=< % int s=0; // mock time-consuming code for (int i=0;i< 1000;i++) { for (int j=0;j< 1000;j++) { s=s+j; } }out.print(s);%> < /body>< /html>