Question

pst = conn.prepareStatement(sql);位置总是出错

package dao.imp;
import java.io.Serializable;
import java.sql.Connection;
import java.sql.PreparedStatement;
import java.sql.ResultSet;
import java.sql.SQLException;
import java.sql.Statement;
import java.util.ArrayList;
import java.util.List;
import com.sun.org.apache.bcel.internal.generic.GETSTATIC;
import dao.StudentDao;
import dao.DBUtil;
import pojo.Student;

public class StudentDaoImp implements StudentDao {
public void insert(Student user) {
Connection conn = DBUtil.getConnection();
String sql = "insert into student values(?,?)";
PreparedStatement pst = null;
try {
pst = conn.prepareStatement(sql);
pst.setString(1, user.getId());
pst.setString(2, user.getName());

pst.executeUpdate();
} catch (SQLException e) {
e.printStackTrace();
} finally {
DBUtil.close(null, pst, conn);
}
}
下面是我的DBUtil程序
package dao;
import java.sql.Connection;
import java.sql.DriverManager;
import java.sql.ResultSet;
import java.sql.SQLException;
import java.sql.Statement;
public class DBUtil {
private static String driver;
private static String url;
private static String user;
private static String password;
static{
try {
driver = "com.mysql.jdbc.Driver";
url = "jdbc:mysql://2:3307/s";
user = "root";
password = "123456";
Class.forName(driver);
} catch (ClassNotFoundException e) {
// TODO Auto-generated catch block
e.printStackTrace();
}
}
public static Connection getConnection(){
try {
return DriverManager.getConnection(url, user, password);
} catch (SQLException e) {
// TODO Auto-generated catch block
e.printStackTrace();
}
return null;
}
public static void close(ResultSet rs,Statement st,Connection conn){
try {
if(rs!=null)
rs.close();
if(st!=null)
st.close();
if(conn!=null)
conn.close();
} catch (SQLException e) {
e.printStackTrace();
}
}
public static void main(String[] args) {
System.out.println(DBUtil.getConnection());
}
}

Answer 1

是在执行的时候报错还是编译的时候报错？没日志怎么看

public void insert(Student user) {
  Connection conn=null;  //干脆也放到try里
  String sql = "insert into student values(?,?)";
  PreparedStatement pst = null;
  try {
  conn = DBUtil.getConnection();
   pst = conn.prepareStatement(sql);
   pst.setString(1, user.getId());
   pst.setString(2, user.getName());
   
   pst.executeUpdate();
  } catch (SQLException e) {
   e.printStackTrace();
  } finally {
   DBUtil.close(null, pst, conn);
  }
 }