Java uses JDBC to call Mysql functions and stored procedures

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foreword

I have used mybatis and mybatis plus to call database functions and stored procedures before. This is also a widely used and popular method at present, but today I encountered a requirement to add function calls to a project. This project is not using mybatis. It's JPA, so I want to find out how to use JPA to call functions, but it seems that there is no particularly good way (maybe I didn't find it).
Later, I found an English answer, using JDBC, and then I tried it to realize the function, and wrote an article to record it.

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1. Examples

For example, we have this table, and now the test uses the function to find out the data we want from this table
±-------±-----------±------- -------+
| Name | DOB | Location |
±-------±-----------±------------- -+
| Amit | 1989-09-26 | Hyderabad |
| Sumith |
1989-09-01
| -----±---------------+

函数如下：
CREATE FUNCTION getDob(emp_name VARCHAR(50)) RETURNS DATE
BEGIN
declare dateOfBirth DATE;
select DOB into dateOfBirth from EMP where Name = emp_name;
return dateOfBirth;
END

2. The main code is as follows

import java.sql.CallableStatement;
import java.sql.Connection;
import java.sql.DriverManager;
import java.sql.SQLException;
import java.sql.Types;
public class CallingFunctionsExample {
    
    
   public static void main(String args[]) throws SQLException {
    
    
	    //Registering the Driver
	    DriverManager.registerDriver(new com.mysql.jdbc.Driver());
	    //Getting the connection
	    //tableName替换为自己的数据库的名字
	    String mysqlUrl = "jdbc:mysql://localhost/tableName";
	    //root替换为自己的数据库的账号名字，12345678为密码
	    Connection con = DriverManager.getConnection(mysqlUrl, "root", "12345678");
	    System.out.println("Connection established......");
	    //Preparing a CallableStatement to call a function
	    //function为所要调用的函数的名字
	    //(?)表示输入参数
	    CallableStatement cstmt = con.prepareCall("{? = call getDob(?)}");
	    //Registering the out parameter of the function (return type)
	    /Types.DATE表示输出参数的类型
	    cstmt.registerOutParameter(1, Types.DATE);
	    //Setting the input parameters of the function
	    //Amit表示输入参数
	    cstmt.setString(2, "Amit");
	    //Executing the statement
	    cstmt.execute();
	    //打印出输出的值
	    System.out.print("Date of birth: "+cstmt.getDate(1));
	}
}

Final output:
Connection established...
Date of birth: 1989-09-26