我想通过jsp

Question

在浏览器中显示一个特定的错误，我做了一个javabean类和error.jsp。问题是这个我想在error.jsp中显示特定的异常。所以我做了错误的变量，我想误差进来错误变量这样我就可以向用户显示....

package mypack; 
import java.sql.Connection; 
import java.sql.DriverManager; 
import java.sql.PreparedStatement; 
import java.sql.ResultSet; 

public class StudentBean { 
    int roll, marks; 
    String name, grade; 
    String error; 
    public String getError() { 
     return error; 
    } 
    public void setError(String error) { 
     this.error = error; 
    } 
    public int getMarks() { 
     return marks; 
    } 
    public String getName() { 
     return name; 
    } 
    public String getGrade() { 
     return grade; 
    } 
    public int getRoll() { 
     return roll; 
    } 
    public void setRoll(int roll) { 
     this.roll = roll; 
    } 
    public boolean lookup() { 
     try { 
      Class.forName("oracle.jdbc.driver.OracleDriver"); 
      Connection con = DriverManager.getConnection(
        "jdbc:oracle:thin:@localhost:1521:xe", "system", "oracle"); 
      PreparedStatement pst = con 
        .prepareStatement("select * from student where roll=?"); 
      pst.setInt(1, roll); 
      ResultSet rs = pst.executeQuery(); 
      if (rs.next()) { 
       name = rs.getString(1); 
       roll = rs.getInt(2); 
       marks = rs.getInt(3); 
       grade = rs.getString(4); 
      } 
     } catch (Exception e) { 
      System.out.println("Generated Exception " + e); 
      error = e.getMessage(); 
     } 
     return true; 
    } 
} 

Answer 1

试图处理所有的异常，这是可能来在你的代码一样