求助：bean出错

Question

public ResultSet selectInfo(int info_id){
try{
pstmt = conn.prepareStatement(SQL);      
pstmt.setInt(1,info_id); rs=pstmt.executeQuery();
return rs;
}catch(SQLException e1){return null;}//查询错误
}参考用

Answer 1

我是用Tomcat4.0的，错误信息如下：A Servlet Exception Has Occurred
org.apache.jasper.JasperException: Unable to compile class for JSPNote: sun.tools.javac.Main has been deprecated.
..\work\localhost\_\_0002fcheckUser_0002ejspcheckUser_jsp_0.java:104: 'try' without 'catch' or 'finally'.
                out.write("\r\n\r\n\r\n");
                ^
..\work\localhost\_\_0002fcheckUser_0002ejspcheckUser_jsp_0.java:108: Type expected.
        } catch (Throwable t) {
          ^
2 errors, 1 warning at org.apache.jasper.compiler.Compiler.compile(Compiler.java:294)
at org.apache.jasper.servlet.JspServlet.doLoadJSP(JspServlet.java:478)
at org.apache.jasper.servlet.JasperLoader12.loadJSP(JasperLoader12.java:146)
at org.apache.jasper.servlet.JspServlet.loadJSP(JspServlet.java:449)
at org.apache.jasper.servlet.JspServlet$JspServletWrapper.loadIfNecessary(JspServlet.java:159)
at org.apache.jasper.servlet.JspServlet$JspServletWrapper.service(JspServlet.java:171)
at org.apache.jasper.servlet.JspServlet.serviceJspFile(JspServlet.java:328)
at org.apache.jasper.servlet.JspServlet.service(JspServlet.java:407)
at javax.servlet.http.HttpServlet.service(HttpServlet.java:853)
at org.apache.catalina.core.ApplicationFilterChain.doFilter(ApplicationFilterChain.java:215)
at org.apache.catalina.core.StandardWrapperValve.invoke(StandardWrapperValve.java:251)
at org.apache.catalina.core.ContainerBase.invoke(ContainerBase.java:977)
at org.apache.catalina.core.StandardContextValve.invoke(StandardContextValve.java:196)
at org.apache.catalina.valves.ValveBase.invokeNext(ValveBase.java:242)
at org.apache.catalina.valves.CertificatesValve.invoke(CertificatesValve.java:242)
at org.apache.catalina.core.ContainerBase.invoke(ContainerBase.java:975)
at org.apache.catalina.core.StandardContext.invoke(StandardContext.java:2041)
at org.apache.catalina.core.StandardHostValve.invoke(StandardHostValve.java:161)
at org.apache.catalina.valves.ValveBase.invokeNext(ValveBase.java:242)
at org.apache.catalina.valves.AccessLogValve.invoke(AccessLogValve.java:414)
at org.apache.catalina.core.ContainerBase.invoke(ContainerBase.java:975)
at org.apache.catalina.core.StandardEngineValve.invoke(StandardEngineValve.java:159)
at org.apache.catalina.core.ContainerBase.invoke(ContainerBase.java:977)
at org.apache.catalina.connector.http.HttpProcessor.process(HttpProcessor.java:818)
at org.apache.catalina.connector.http.HttpProcessor.run(HttpProcessor.java:897)
at java.lang.Thread.run(Thread.java:536)为何会这样？请帮帮我。

Answer 2

还有我已经把conn=null删除掉了还是这样。

Answer 3

给你个完整的BEAN,这是我现在做项目用的，不会有问题的
package beans;import java.io.PrintStream;
import java.sql.*;
import java.util.ResourceBundle;
import java.lang.*;public class sql_data
{ ResourceBundle bundle=ResourceBundle.getBundle("db_config");
        
        String sDBDriver=bundle.getString("sDBDriver");
        String sConnStr=bundle.getString("sConnStr");
        String username=bundle.getString("username");
        String password=bundle.getString("password");    Connection conn;
    Statement stmt;
    ResultSet rs;    public sql_data()
    {         conn = null;
        stmt = null;
        rs = null;
        try
        {
            Class.forName(sDBDriver); 
        }
        catch(ClassNotFoundException classnotfoundexception)
        {
            System.err.println("sql_data(): " + classnotfoundexception.getMessage());
        }
    }    public void executeInsert(String s)
    {
        try
        {
            conn = DriverManager.getConnection(sConnStr,username,password);
            stmt = conn.createStatement(1004, 1007);
            stmt.executeUpdate(s);
            stmt.close();
            conn.close();
        }
        catch(SQLException sqlexception)
        {
            System.err.println("sql_data.executeUpdate:" + sqlexception.getMessage());
        }
    }    public ResultSet executeQuery(String s)
    {
        rs = null;
        try
        {
            conn = DriverManager.getConnection(sConnStr,username,password);
            Statement statement = conn.createStatement(1004, 1007);
            rs = statement.executeQuery(s);
        }
        catch(SQLException sqlexception)
        {
            System.err.println("aq.executeQuery: " + sqlexception.getMessage());
            System.err.println("aq.executeQuerystrSQL: " + s);
        }
        return rs;
    }    public void executeUpdate(String s)
    {
        try
        {
            conn = DriverManager.getConnection(sConnStr,username,password);
            Statement statement = conn.createStatement(1004, 1007);
            statement.executeUpdate(s);
        }
        catch(SQLException sqlexception)
        {
            System.err.println("aq.executeUpdate: " + sqlexception.getMessage());
            System.err.println("aq.executeUpadatestrSQL: " + s);
        }
    }    public void executeDelete(String s)
    {
        try
        {
            conn = DriverManager.getConnection(sConnStr,username,password);
            stmt = conn.createStatement(1004, 1007);
            stmt.executeUpdate(s);
            stmt.close();
            conn.close();
        }
        catch(SQLException sqlexception)
        {
            System.err.println("sql_data.executeDelete:" + sqlexception.getMessage());
        }
    }    public void closeStmt()
    {
        try
        {
            stmt.close();
        }
        catch(SQLException sqlexception)
        {
            sqlexception.printStackTrace();
        }
    }    public void closeConn()
    {
        try
        {
            conn.close();
        }
        catch(SQLException sqlexception)
        {
            sqlexception.printStackTrace();
        }
    }
}

Answer 4

..\work\localhost\_\_0002fcheckUser_0002ejspcheckUser_jsp_0.java:104: 'try' without 'catch' or 'finally'.
                out.write("\r\n\r\n\r\n");
                ^
..\work\localhost\_\_0002fcheckUser_0002ejspcheckUser_jsp_0.java:108: Type expected.
        } catch (Throwable t) {
          ^
2 errors, 1 warning以上的信息都很明显的告诉你错在什么地方啦。
肯定是你的程序中少了(或多了）大括号"}"

Answer 5

根据错误信息，应该是在你的jsp页里少了 “}”。
请检查你的jsp代码的try-catch代码段。