java.sql.SQLException: [Microsoft][ODBC Microsoft Access Driver] 由于将在索引、 主关键字、或关系中创建重复的值，请求对表的改变没有成功。 改变该字段中的或包含重复数据的字段中的数据，删除索引或重新定义索引以允许重复的值并再试一次。
代码：

public void actionPerformed(ActionEvent e) {
        // TODO Auto-generated method stub
        if(e.getSource()==jbt1)
        {
            Connection con=null;
            PreparedStatement st=null;
            ResultSet re=null;
            try{
                  //加载驱动
                 Class.forName("sun.jdbc.odbc.JdbcOdbcDriver");
                 //得到连接(连接到数据源)
                 con=DriverManager.getConnection("jdbc:odbc:STUDB");
                 //创建语句（发送SQL语句得到数据库）
                 String stu1=" insert into student1 values(?,?,?,?,?)";
                 st=con.prepareStatement(stu1);
                 st.setString(1, jtf1.getText());
                 st.setString(2, jtf2.getText());
                 st.setString(3, jtf3.getText());
                 st.setString(4, jtf4.getText());
                 st.setString(5, jtf5.getText());
                 
                 st.executeUpdate();
                 this.dispose();
                 
                 
                 }catch(Exception c)
                 {
                     c.printStackTrace();
                 }finally{
                     try{
                         if(re!=null) re.close();
                         if(st!=null) st.close();
                         if(con!=null) con.close();
                     }catch(Exception c)
                     {
                         c.printStackTrace();
                         }
                     }