📄 672175.xml
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<Point>0</Point>
<Content>如何才能看出rs=view.executeQuery("select * from user_info");
  是否执行了呢？</Content>
<PostDateTime>2002-4-24 14:34:03</PostDateTime>
</Reply>
<Reply>
<PostUserNickName>灵子</PostUserNickName>
<rank>二级(初级)</rank>
<ranknum>user2</ranknum>
<credit>97</credit>
<ReplyID>4418593</ReplyID>
<TopicID>672175</TopicID>
<PostUserId>159900</PostUserId>
<PostUserName>lingzi</PostUserName>
<Point>0</Point>
<Content>我的access_dbconnect.class内容如下：
package access;
import java.sql.*;
public class access_dbconnect{
       String sDBDriver="sun.jdbc.odbc.jdbcOdbcDriver";
       String sConnStr="jdbc:odbc:Access_test";
       Connection conn=null;
       ResultSet rs=null;
       public access_dbconnect(){
              try{
                  Class.forName(sDBDriver);
              }
              catch(java.lang.ClassNotFoundException e){
                    System.err.println("Class access_dbconnect not fount!"+e.getMessage());
                     }
       }
   
       public ResultSet executeQuery(String sql){
              rs=null;
              try{
                  conn=DriverManager.getConnection(sConnStr);
                  Statement stmt=conn.createStatement();
                  rs=stmt.executeQuery(sql);
               }
              catch(SQLException ex){
                     System.err.println("aq.executeQuery:"+ex.getMessage());
               }
               return rs;
       }
       public ResultSet executeUpdate(String sql){
              rs=null;
              try{
                  conn=DriverManager.getConnection(sConnStr);
                  Statement stmt=conn.createStatement();
                  rs=stmt.executeQuery(sql);
             }
              catch(SQLException ex){
                    System.err.println("aq.executeQuery:"+ex.getMessage());
             }
             return rs;
    }
}</Content>
<PostDateTime>2002-4-24 14:36:15</PostDateTime>
</Reply>
<Reply>
<PostUserNickName>卧龙</PostUserNickName>
<rank>四级(中级)</rank>
<ranknum>user4</ranknum>
<credit>100</credit>
<ReplyID>4418844</ReplyID>
<TopicID>672175</TopicID>
<PostUserId>223374</PostUserId>
<PostUserName>wjfxiao</PostUserName>
<Point>0</Point>
<Content>你可以在jsp页面加try{}和catch()
你在
}
   
       public ResultSet executeQuery(String sql){
              rs=null;
              try{
                  conn=DriverManager.getConnection(sConnStr);
                  Statement stmt=conn.createStatement();
                  rs=stmt.executeQuery(sql);
               }
              catch(SQLException ex){
                     System.err.println("aq.executeQuery:"+ex.getMessage());
               }
               return rs;
       }
     中加一句：  
                  rs=stmt.executeQuery(sql);
              if(rs == null)
{
      System.out.println("can't get ResultSet");
}
//add
               }
              catch(SQLException ex){
                     
这样试一试，看错处在那儿！
</Content>
<PostDateTime>2002-4-24 14:49:33</PostDateTime>
</Reply>
<Reply>
<PostUserNickName>卧龙</PostUserNickName>
<rank>四级(中级)</rank>
<ranknum>user4</ranknum>
<credit>100</credit>
<ReplyID>4418947</ReplyID>
<TopicID>672175</TopicID>
<PostUserId>223374</PostUserId>
<PostUserName>wjfxiao</PostUserName>
<Point>0</Point>
<Content>还有，你的ResultSet,Statement,Connection用完都没有关闭。
应调用它们的close()方法。
你还可以把得到连接，创建Statement写成一个方法，
在其他方法中调用即可，不用写多次</Content>
<PostDateTime>2002-4-24 14:54:06</PostDateTime>
</Reply>
<Reply>
<PostUserNickName>阿峰</PostUserNickName>
<rank>二级(初级)</rank>
<ranknum>user2</ranknum>
<credit>100</credit>
<ReplyID>4419046</ReplyID>
<TopicID>672175</TopicID>
<PostUserId>85055</PostUserId>
<PostUserName>donny2000</PostUserName>
<Point>0</Point>
<Content>Bean的错误</Content>
<PostDateTime>2002-4-24 14:58:22</PostDateTime>
</Reply>
<Reply>
<PostUserNickName>灵子</PostUserNickName>
<rank>二级(初级)</rank>
<ranknum>user2</ranknum>
<credit>97</credit>
<ReplyID>4420347</ReplyID>
<TopicID>672175</TopicID>
<PostUserId>159900</PostUserId>
<PostUserName>lingzi</PostUserName>
<Point>0</Point>
<Content>package access;
import java.sql.*;
public class access_dbconnect{
       String sDBDriver="sun.jdbc.odbc.jdbcOdbcDriver";
       String sConnStr="jdbc:odbc:Access_test";
       Connection conn=null;
       ResultSet rs=null;
       public access_dbconnect(){
              try{
                  Class.forName(sDBDriver);
              }
              catch(java.lang.ClassNotFoundException e){
                    System.err.println("Class access_dbconnect not fount!"+e.getMessage());
                     }
       }
   
       public ResultSet executeQuery(String sql){
              rs=null;
              try{
                  conn=DriverManager.getConnection(sConnStr);
                  Statement stmt=conn.createStatement();
                  rs=stmt.executeQuery(sql);
                  if(rs == null)     //**********************************
                {
                  System.out.println("can't get ResultSet"); //**********************************
                }                    //**********************************
               }
              catch(SQLException ex){
                     System.err.println("aq.executeQuery:"+ex.getMessage());
               }
               return rs;
               
       }
       public ResultSet executeUpdate(String sql){
              rs=null;
              try{
                  conn=DriverManager.getConnection(sConnStr);
                  Statement stmt=conn.createStatement();
                  rs=stmt.executeQuery(sql);
             }
              catch(SQLException ex){
                    System.err.println("aq.executeQuery:"+ex.getMessage());
             }
             return rs;
    }
}
按照卧龙您的方法但是无论是if(rs == null)还是if(rs != null),都不出现"can't get ResultSet"这是怎么回事?
我的ODBC数据源是这样设置的：开始、设置、控制面版，OCBC数据源、系统DSN、添加、MICROSOFT ACCESS DRIVER（*.mdb）、选取、找user_test.mdb、数据源名“Access_test”、确定。
数据库名字user_test,库里的表是user_info,字段name,sex,address，ID而且我添加了三条记录。
我的view.jsp是放在根目录下的。我的access_dbconnect.class是放在相对于根目录的WEB-INF\classes下的。数据库也是放在根目录下了。</Content>
<PostDateTime>2002-4-24 16:00:22</PostDateTime>
</Reply>
<Reply>
<PostUserNickName>卧龙</PostUserNickName>
<rank>四级(中级)</rank>
<ranknum>user4</ranknum>
<credit>100</credit>
<ReplyID>4420749</ReplyID>
<TopicID>672175</TopicID>
<PostUserId>223374</PostUserId>
<PostUserName>wjfxiao</PostUserName>
<Point>0</Point>
<Content>现在报什么错？
在classes目录下新建一access目录，把access_dbconnect.class
放到这个目录下面试试。</Content>
<PostDateTime>2002-4-24 16:21:41</PostDateTime>
</Reply>
<Reply>
<PostUserNickName>灵子</PostUserNickName>
<rank>二级(初级)</rank>
<ranknum>user2</ranknum>
<credit>97</credit>
<ReplyID>4421280</ReplyID>
<TopicID>672175</TopicID>
<PostUserId>159900</PostUserId>
<PostUserName>lingzi</PostUserName>
<Point>0</Point>
<Content>我已经在classes目录下建立access目录了。还是不行。
</Content>
<PostDateTime>2002-4-24 16:47:20</PostDateTime>
</Reply>
<Reply>
<PostUserNickName>卧龙</PostUserNickName>
<rank>四级(中级)</rank>
<ranknum>user4</ranknum>
<credit>100</credit>
<ReplyID>4421896</ReplyID>
<TopicID>672175</TopicID>
<PostUserId>223374</PostUserId>
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