tomcat问题.每隔一段时间就需要重启一下远程空间的TOCMAT?

日志报错:set.java.sql.SQLException: Illegal operation on empty result set.org.apache.tomcat.dbcp.dbcp.SQLNestedException: Cannot get a connection, pool error Timeout waiting for idle object不能连接到数据源
怀疑有连接没有关闭.请帮忙看看代码.谢谢
DBConnSource.java:

*
 * 数据源连接BEAN
  */
package mybean;

import java.sql.*;
import javax.sql.*;
import javax.naming.*;

public class DBConnSource {
    private Connection conn;
    private Statement stmt;
    private PreparedStatement pstmt;
    public DBConnSource(String dsName){
        try{
            Context initCtx = new InitialContext();
            Context ctx =(Context)initCtx.lookup("java:comp/env");
            DataSource ds =(DataSource)ctx.lookup(dsName);
            conn = ds.getConnection();
        }
        catch(Exception e)
        {
            System.out.print(e.toString());
        }
    }
    public synchronized Statement getStmt()throws Exception
    {
        stmt=conn.createStatement();
        return stmt;
    }
    public synchronized PreparedStatement getPstmt(String sql)throws Exception
    {
        pstmt=conn.prepareStatement(sql);
        return pstmt;
    }
    public void DBclose(){
        try{             //关闭 Connection conn;
            if(conn!=null){
            conn.close();
            }
        }catch(Exception e){
            System.out.print(e.toString());
        }finally{
            conn=null;
        }
        
        try{               //关闭Statement stmt;
            if(stmt!=null){
            stmt.close();
            }
        }catch(Exception e){
            System.out.print(e.toString());
        }finally{
            stmt=null;
        }
        
        try{               //关闭 PreparedStatement pstmt;
            if(pstmt!=null){
            pstmt.close();
            }
        }catch(Exception e){
            System.out.print(e.toString());
        }finally{
            pstmt=null;
        }
    }
}

stylelist.java:

/*
 * 网站JAVABEAN
 * 所有帖子分类列表.
 * 使用数据源连接.
 * 前后台共用JAVABEAN.
 */
package mybean;

import java.sql.*;

import mybean.DBConnSource;

public class StyleList {


    private String tableName;
    private Statement stmt;
    private ResultSet rs;
    private DBConnSource dbc; 
    
    public StyleList(){}
    
    public void setTableName(String n){
        this.tableName=n;
    }
    
    public StringBuffer getBuffer(){
        StringBuffer buffer=new StringBuffer();
        dbc=new DBConnSource("jdbc/myweb");
           try{
            
            stmt=dbc.getStmt(); 
            }catch(Exception e){
                        System.out.print("不能连接到数据源");
            }
             
         try{
             String strSql="SELECT * FROM "+tableName; 
             rs = stmt.executeQuery(strSql);
             
             while(rs.next()){                    
                buffer.append("<a href='style.jsp?style="+rs.getString("style")+"' target=_blank>"+rs.getString("style")+"</a>");
                buffer.append("&nbsp;&nbsp;&nbsp;");
                }               
        }catch(SQLException e){
            System.out.print(e.toString());
        }finally{
            try{               //关闭 ResultSet rs.
                   if(rs!= null){
                   rs.close();}
                }catch(SQLException ex){
                   System.out.print(ex.toString());
                }finally{
                   rs=null;
                }                
                 
            try{               // 关闭 Statement stmt. 
                    if(stmt!= null){
                    stmt.close();}
                 }catch(SQLException ex){
                    System.out.print(ex.toString());
                 }finally{
                    stmt=null;
                 }        
             dbc.DBclose();  //关闭 DBConnsource dbc;        
        }
         return buffer;
    }
}

远程空间的日志报错:
java.sql.SQLException: Illegal operation on empty result set.org.apache.tomcat.dbcp.dbcp.SQLNestedException: Cannot get a connection, pool error Timeout waiting for idle object不能连接到数据源
搞了很长时间,头都大了.
谢谢!

2 个解决方案

#1

conn = null能正常关闭连接吗？没这么用过

#2

谢谢.你说的很对.那个conn=null是多余的.