jsp 动态加载

动态加载 jsp 文件
<?xml version="1.0" encoding="UTF-8"?>
<web-app version="2.5"
xmlns="http://java.sun.com/xml/ns/javaee"
xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"
xsi:schemaLocation="http://java.sun.com/xml/ns/javaee
http://java.sun.com/xml/ns/javaee/web-app_2_5.xsd">
<filter>
<filter-name>viewPage</filter-name>
<filter-class>
ywl.PageFilter
</filter-class>
</filter>
<filter-mapping>
<filter-name>viewPage</filter-name>
<url-pattern>/cms/*</url-pattern>
<dispatcher>REQUEST</dispatcher>
<dispatcher>FORWARD</dispatcher>
</filter-mapping>
  <welcome-file-list>
    <welcome-file>index.jsp</welcome-file>
  </welcome-file-list>
</web-app>

package ywl;

import java.io.File;
import java.io.FileWriter;
import java.io.IOException;
import java.io.Reader;

import javax.servlet.Filter;
import javax.servlet.FilterChain;
import javax.servlet.FilterConfig;
import javax.servlet.ServletContext;
import javax.servlet.ServletException;
import javax.servlet.ServletRequest;
import javax.servlet.ServletResponse;
import javax.servlet.http.HttpServletRequest;

public class PageFilter implements Filter {
private ServletContext servletContext;
public void init(FilterConfig config) throws ServletException {
this.servletContext = config.getServletContext();
}

public void doFilter(ServletRequest req, ServletResponse resp,
FilterChain chain) throws IOException, ServletException {
HttpServletRequest request = (HttpServletRequest) req;
// HttpServletResponse response = (HttpServletResponse) resp;
String requestURI = request.getRequestURI();
int cpLength = request.getContextPath().length();
String uri = requestURI.substring(cpLength, requestURI.length());
try {
this.fetchJspFile(uri);
} catch (Exception ae) {
resp.setContentType("text/html; charset=GB18030");
throw new ServletException(ae);
}
chain.doFilter(req, resp);
}

private synchronized void fetchJspFile(String uri) throws IOException {
String realPath = this.servletContext.getRealPath(uri);
File jspFile = new File(realPath);

// String fileName = uri.substring(uri.lastIndexOf('/') + 1, uri.length());
FileWriter jspFileWriter = new FileWriter(jspFile);
Reader reader = null;
try {
String jspContent = "aaaaa";
jspFileWriter.write(jspContent);
jspFileWriter.flush();
} finally {
jspFileWriter.close();
if (reader != null) {
reader.close();
}
}
}

public void destroy() {
}
}