基础问题，急急急，谁能帮帮我啊？？？？？？

Question

ResultSet resut;
             
            Statement stmt=con.createStatement(); 
try{  
            resut=stmt.executeQuery("select * from biao");  //发送SQL语句
           if(resut.next()){
            System.out.println(resut.getString(1));}
           
           
            dma=con.getMetaData();
            ResultSet rrr;
            rrr=dma.getTables(null,null,"%",null);    //返回数据库中所有表
            if(rrr.next()){
            System.out.println(rrr.getString(1));}
}catch(Exception e){}

Answer 1

天知道你报的什么错，再说如果从数据库没查到数据的话会返回null，直接resut.next()肯定报错，楼上写得对

Answer 2

try
          {
            ResultSet resut;
            Statement stmt=con.createStatement();   
            resut=stmt.executeQuery("select * from biao");  //发送SQL语句
            if (resut.next())
            System.out.println(resut.getString(1));
           }
           catch(Exception ex)
           {
                ex.printStackTrace();
            }
           
           try
          { 
            dma=con.getMetaData();
            ResultSet rrr;
            rrr=dma.getTables(null,null,"%",null);    //返回数据库中所有表
            
            if(rrr.next())
               System.out.println(rrr.getString(1));
          }         
          catch(Exception ex)
          {
               ex.printStackTrace()
          }

Answer 3

try
          {
            ResultSet resut;
            Statement stmt=con.createStatement();   
            resut=stmt.executeQuery("select * from biao");  //发送SQL语句
            if (resut.next())
            System.out.println(resut.getString(1));
           }
           catch(Exception dbe)//数据库连接错误
           {
                ex.printStackTrace();
            }
           
           try
          { 
            dma=con.getMetaData();
            ResultSet rrr;
            rrr=dma.getTables(null,null,"%",null);    //返回数据库中所有表
            
            if(rrr.next())
               System.out.println(rrr.getString(1));
          }         
          catch(Exception dbe)//数据库连接错误
          {
               ex.printStackTrace()
          }