date datatype should be of varchar type.

import java.sql.*;
import java.util.*;
import java.text.*
class  InsertDate{
    public static void main(String[] args){
    try{
        java.util.Date d=new java.util.Date();
        SimpleDateFormat sdf=new SimpleDateFormat("MM-dd-yyyy");
        String st=sdf.format(d);
        Class.forName("com.mysql.jdbc.Driver").newInstance();
        Connection conn = DriverManager.getConnection("jdbc:mysql://localhost:3306/test", "root", "root" );

        Statement pstmt = conn.createStatement();
        String INSERT_RECORD = "insert into person(dob) values('"+st+"')";
        pstmt.executeUpdate(INSERT_RECORD);
        pstmt.close();
        conn.close();
    }
    catch(Exception e){
        e.printStackTrace();
    }
  }
}

The package java.util.* and java.sql.*, both are having Date class. Therefore this error occurs. Use classes with their package as well like if you are using Date class of util package then use it as java.util.Date and if you are using java.sql.Date then use it as java.sql.Date.

Thanks ! Helped Very Much ! :D