菜鸟求助啊 HTTP Status 500 - java.lang.NullPointerException

2013-6-12 14:03:47 org.apache.catalina.core.StandardWrapperValve invoke
严重: Servlet.service() for servlet [jsp] in context with path [/Work] threw exception [java.lang.NullPointerException] with root cause
java.lang.NullPointerException
at org.apache.jsp.searchResult_jsp._jspService(searchResult_jsp.java:107)
at org.apache.jasper.runtime.HttpJspBase.service(HttpJspBase.java:70)
at javax.servlet.http.HttpServlet.service(HttpServlet.java:728)
at org.apache.jasper.servlet.JspServletWrapper.service(JspServletWrapper.java:432)
at org.apache.jasper.servlet.JspServlet.serviceJspFile(JspServlet.java:390)
at org.apache.jasper.servlet.JspServlet.service(JspServlet.java:334)
at javax.servlet.http.HttpServlet.service(HttpServlet.java:728)
at org.apache.catalina.core.ApplicationFilterChain.internalDoFilter(ApplicationFilterChain.java:305)
at org.apache.catalina.core.ApplicationFilterChain.doFilter(ApplicationFilterChain.java:210)
at org.apache.catalina.core.StandardWrapperValve.invoke(StandardWrapperValve.java:222)
at org.apache.catalina.core.StandardContextValve.invoke(StandardContextValve.java:123)
at org.apache.catalina.authenticator.AuthenticatorBase.invoke(AuthenticatorBase.java:472)
at org.apache.catalina.core.StandardHostValve.invoke(StandardHostValve.java:171)
at org.apache.catalina.valves.ErrorReportValve.invoke(ErrorReportValve.java:99)
at org.apache.catalina.valves.AccessLogValve.invoke(AccessLogValve.java:936)
at org.apache.catalina.core.StandardEngineValve.invoke(StandardEngineValve.java:118)
at org.apache.catalina.connector.CoyoteAdapter.service(CoyoteAdapter.java:407)
at org.apache.coyote.http11.AbstractHttp11Processor.process(AbstractHttp11Processor.java:1004)
at org.apache.coyote.AbstractProtocol$AbstractConnectionHandler.process(AbstractProtocol.java:589)
at org.apache.tomcat.util.net.JIoEndpoint$SocketProcessor.run(JIoEndpoint.java:312)
at java.util.concurrent.ThreadPoolExecutor$Worker.runTask(ThreadPoolExecutor.java:886)
at java.util.concurrent.ThreadPoolExecutor$Worker.run(ThreadPoolExecutor.java:908)
at java.lang.Thread.run(Thread.java:619)求各位大大帮忙啊   折腾好久了T_T

解决方案 »

  1.   

    NullPointerException 这个只能检查代码了
      

  2.   

    package servlet;import java.io.IOException;
    import java.io.PrintWriter;import javax.servlet.ServletException;
    import javax.servlet.http.HttpServlet;
    import javax.servlet.http.HttpServletRequest;
    import javax.servlet.http.HttpServletResponse;
    import javax.servlet.http.HttpSession;import com.DBUtil.DBCon;
    import com.javabean.Searchbean;
    import java.sql.*;
    public class SearchServlet extends HttpServlet { /**
     * Constructor of the object.
     */
    public SearchServlet() {
    super();
    } /**
     * Destruction of the servlet. <br>
     */
    public void destroy() {
    super.destroy(); // Just puts "destroy" string in log
    // Put your code here
    } /**
     * The doGet method of the servlet. <br>
     *
     * This method is called when a form has its tag value method equals to get.
     * 
     * @param request the request send by the client to the server
     * @param response the response send by the server to the client
     * @throws ServletException if an error occurred
     * @throws IOException if an error occurred
     */
    public void doGet(HttpServletRequest request, HttpServletResponse response)
    throws ServletException, IOException { response.setContentType("text/html");
    PrintWriter out = response.getWriter();
    out.println("<!DOCTYPE HTML PUBLIC \"-//W3C//DTD HTML 4.01 Transitional//EN\">");
    out.println("<HTML>");
    out.println("  <HEAD><TITLE>A Servlet</TITLE></HEAD>");
    out.println("  <BODY>");
    out.print("    This is ");
    out.print(this.getClass());
    out.println(", using the GET method");
    out.println("  </BODY>");
    out.println("</HTML>");
    out.flush();
    out.close();
    } /**
     * The doPost method of the servlet. <br>
     *
     * This method is called when a form has its tag value method equals to post.
     * 
     * @param request the request send by the client to the server
     * @param response the response send by the server to the client
     * @throws ServletException if an error occurred
     * @throws IOException if an error occurred
     */
    public void doPost(HttpServletRequest request, HttpServletResponse response)
    throws ServletException, IOException {
    HttpSession session = request.getSession();
    String searchName = request.getParameter("result");
    System.out.println(searchName);
    Searchbean sb = new Searchbean();
    DBCon dbc =new DBCon();
    Connection conn =dbc.getConn();
    Statement stmt =dbc.getStmt(conn);
    ResultSet rs = dbc.getResultset(stmt, "select * from [movie] where name = '"+searchName+"'");
    try {
    while(rs.next()){
    String name= rs.getString("name");
    sb.setStrname(rs.getString("name"));
    sb.setDirector(rs.getString("director"));
    sb.setActor(rs.getString("actor"));
    sb.setLanguage(rs.getString("language"));
    sb.setDictrict(rs.getString("distric"));
    sb.setDate(rs.getString("date"));
    sb.setImage(rs.getString("url"));
    System.out.println(name);
    System.out.println("数据读取成功");
    session.setAttribute("sb",sb );

    }
    } catch (SQLException e) {
    // TODO Auto-generated catch block
    e.printStackTrace();
    }
    response.sendRedirect("searchResult.jsp");

    } /**
     * Initialization of the servlet. <br>
     *
     * @throws ServletException if an error occurs
     */
    public void init() throws ServletException {
    // Put your code here
    }}
      

  3.   

     哪个页面 调用哪个servlet的时候出的问题呢。。
      

  4.   

    今天刚遇到这个问题 也是弄了好久才解决的 刚开始以为是文件路径写错了, 查了半天结果是连接数据库的 connection还没有用完就关闭了,完美解决 ,仔细检查一下代码是不是什么东西没有用完就关闭了,希望对楼主有帮助;