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Updated on 2025-04-06

Step by step explanation of Spring Boot's practical guide to integrating MyBatis and PostgreSQL

Preface

In today's enterprise-level Java development scenarios, Spring Boot can efficiently build a stable and high-performance application system thanks to its convenient configuration and fast startup capabilities, combined with the powerful persistence layer framework MyBatis and the open-source relational database PostgreSQL. This article will introduce in detail how to complete the seamless integration of these three step by step to help developers quickly get started with project development.

1. Environment construction and preparation

  • JDK installation: Make sure that the local environment has JDK 8 and above installed, by entering it on the command linejava -versionTo verify the installation status and version information, and ensure that the JDK environment variables are correctly configured so that subsequent projects can be compiled and run.
  • Maven configuration: Install and configure Maven, this is a powerful tool for Java project dependency management and construction. Available inSetting domestic mirror sources in the file, such as Alibaba Cloud mirror, accelerates the download speed of dependent packages and reduces project initialization time.
  • PostgreSQL database installation: Go to the official PostgreSQL website to download the installation package of the corresponding operating system and follow the installation wizard to complete the installation of the database service. During the installation process, you need to keep in mind the password set (usually postgres) and will be used when connecting to the database in the future. Create the database instance required for the project, for example, calledyour_database, and record the connection address, the format is generallyjdbc:postgresql://localhost:5432/your_database,in5432It is the default port number and is adjusted according to the actual configuration.

2. Create Spring Boot Project

With Spring Initializr, this feature is built into most mainstream integrated development environments (such as IDEA, Eclipse, etc.). When creating a new project, checkWeb、MyBatis Frameworkas well asPostgreSQL DriverDependencies, Spring Initializr will automatically generate a project skeleton containing the necessary directory structure and initial configuration files. The key directories includesrc/main/java(used to store Java source code),src/main/resources(Put configuration files, static resources, and mapping files for MyBatis, etc.).

3. Data source and MyBatis configuration

existsrc/main/resources/Accurate configuration of PostgreSQL data source information in the file:

=jdbc:postgresql://localhost:5432/your_database
=postgres
=your_password
-class-name=

Pay attention toyour_passwordReplace it with the actual database password to ensure the connection configuration is accurate.

Then configure MyBatis to set the entity class alias to scan the package path, so as to facilitate the simple reference of entity classes in the XML mapping file, and at the same time specify the location of the Mapper XML file:

-aliases-package=
-locations=classpath:mapper/*.xml

4. Entity class and Mapper interface definition

existThe package carefully constructs entity classes corresponding to the database table structure, such as creatingUserEntity class:

import ;

@Data
public class User {
    private Long id;
    private String name;
    private Integer age;
}

Here with Lombok's@DataAnnotations simplify the conventionalget、set、equals、hashCodeetc. If Lombok is not introduced, these methods need to be generated manually.

AtCreate in packageUserMapperInterface, use@MapperAnnotation mark (if the Spring Boot starts the package and its subpackage, the annotation can be omitted, and Spring will automatically scan), define the database operation method, such as querying the method signature of all users:

import ;
import ;
import ;

@Mapper
public interface UserMapper {
    List<User> getAllUsers();
}

5. Write Mapper XML files

existsrc/main/resources/mapperCreate new in the directory, carefully write SQL statements andUserMapperThe interface methods echo:

<?xml version="1.0" encoding="UTF-8"?>
<!DOCTYPE mapper PUBLIC "-////DTD Mapper 3.0//EN" "/dtd/">
<mapper namespace="">
    <select  resultMap="BaseResultMap">
        SELECT * FROM users_table
    </select>
    <resultMap  type="">
        <id property="id" column="id"/>
        <result property="name" column="name"/>
        <result property="age" column="age"/>
    </resultMap>
</mapper>

Need to pay attentionSELECTTable name in the statementusers_tableIt should be consistent with the table name in the actual database.resultMapAccurately map database columns and entity class attributes.

6. Implementation of business layer and control layer

Business layerPackage definitionUserServiceInterface and specific implementation categoriesUserServiceImplThe business logic layer is responsible for coordinating the interaction between the data access layer (Mapper) and the control layer, and passes through the implementation class.@AutowiredAnnotation injectionUserMapperExample:

import ;
import ;

public interface UserService {
    List<User> getAllUsers();
}

import ;
import ;
import ;
import ;
import ;

@Service
public class UserServiceImpl implements UserService {
    @Resource
    private UserMapper userMapper;

    @Override
    public List<User> getAllUsers() {
        return ();
    }
}

Control layerPackage creationUserController, use@RestControllerand@RequestMappingAnnotation to the outside world

import ;
import ;
import ;
import ;
import ;
import ;
import ;

@RestController
@RequestMapping("/users")
public class UserController {
    @Resource
    private UserService userService;

    @GetMapping
    public List<User> getUsers() {
        return ();
    }
}

7. Testing and verification

Start Spring Boot project main classDemoApplication, After the project is successfully started, access it in a browser or Postman and other tools.http://localhost:8080/users(Port number according tomiddleDepending on configuration, the path is based on@RequestMappingSettings), if databaseyour_databaseofusers_tableThere is data in the table, and you should be able to see the list of user information returned in JSON format, which means that the integration is completed.

In the future, you can further expand complex business logic based on the actual needs of the project, and deeply explore the advanced features of MyBatis such as dynamic SQL, caching mechanism, and many practical functions of Spring Boot, such as security authentication, performance tuning, etc., continuously optimize the performance and functional integrity of the application system, and start an efficient and robust back-end development journey.

The above code snippets are only basic integration examples. In actual project development, you need to closely adapt and optimize the business scenarios flexibly. I hope this tutorial will become your right-hand assistant on the road to technological advancement.

This is the end of this article about Spring Boot integrating MyBatis and PostgreSQL. For more related content related to Spring Boot integrating MyBatis and PostgreSQL, please search for my previous articles or continue browsing the related articles below. I hope everyone will support me in the future!