idea 环境下 mybatis连接数据库实现增删改查

Bertha 。 2022-12-13 04:50 123阅读 0赞

# 一、什么是Mybatis #

这里借用官网的一句话介绍什么是mybatis：MyBatis 是一款优秀的持久层框架，它支持定制化 SQL、存储过程以及高级映射。MyBatis 避免了几乎所有的 JDBC 代码和手动设置参数以及获取结果集。MyBatis 可以使用简单的 XML 或注解来配置和映射原生信息，将接口和 Java 的 POJOs(Plain Old Java Objects,普通的 Java对象)映射成数据库中的记录。

#  #

# 第一步 搭建maven环境 #

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# 第二步填写包名 #

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# 第三步在新建的项目中找到pom.xml文件 #

添加mybatis mysql 还有junit（单元测试）的依赖

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添加Mybatis依赖代码（此处注意一些遇到的异常处理，看备注）

<?xml version="1.0" encoding="UTF-8"?>
    <project xmlns="http://maven.apache.org/POM/4.0.0"
             xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"
             xsi:schemaLocation="http://maven.apache.org/POM/4.0.0 http://maven.apache.org/xsd/maven-4.0.0.xsd">
        <modelVersion>4.0.0</modelVersion>
        <groupId>com.org.Ssm</groupId>
        <artifactId>ssm</artifactId>
        <version>1.0-SNAPSHOT</version>
    
        
        <properties>
            <project.build.sourceEncoding>UTF-8</project.build.sourceEncoding>
        </properties>
        <dependencies>
    
            
            <dependency>
                <groupId>org.mybatis</groupId>
                <artifactId>mybatis</artifactId>
                <version>3.5.2</version>
            </dependency>
            
            
            <dependency>
                <groupId>org.apache.logging.log4j</groupId>
                <artifactId>log4j</artifactId>
                <version>2.11.2</version>
            </dependency>
            
            <dependency>
                <groupId>mysql</groupId>
                <artifactId>mysql-connector-java</artifactId>
                <version>8.0.18</version>
                <scope>runtime</scope>
            </dependency>
      
            <dependency>
                <groupId>junit</groupId>
                <artifactId>junit</artifactId>
                <version>4.12</version>
                <scope>test</scope>
            </dependency>
            <dependency>
                <groupId>junit</groupId>
                <artifactId>junit</artifactId>
                <version>4.12</version>
                <scope>compile</scope>
            </dependency>
        </dependencies>
        <build>
            <resources>
               
                <resource>
                    <directory>src/main/resources</directory>
                    <filtering>true</filtering>
                </resource>
                <resource>
                    <directory>src/main/java</directory>
                    <filtering>true</filtering>
                </resource>
            </resources>
            
            <plugins>
                <plugin>
                    <groupId>org.apache.maven.plugins</groupId>
                    <artifactId>maven-resources-plugin</artifactId>
                    <configuration>
                        <encoding>UTF-8</encoding>
                    </configuration>
                </plugin>
            </plugins>
        </build>
    
    </project>

# 第四步配置mybatis核心配置文件（此处注意配置文件所在的位置，和文件中配置变量的注意事项） #

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<?xml version="1.0" encoding="UTF-8"?>
    <!DOCTYPE configuration
            PUBLIC "-//mybatis.org//DTD Config 3.0//EN"
            "http://mybatis.org/dtd/mybatis-3-config.dtd">
    <configuration>
        
        <environments default="mysql">
            <environment id="mysql">
                
                <transactionManager type="JDBC"></transactionManager>
                
                <dataSource type="POOLED">
                    
                    <property name="driver" value="com.mysql.cj.jdbc.Driver"/>
                    
                    
                    <property name="url" value="jdbc:mysql://localhost:3306/gxftest?serverTimezone=UTC"/>
                    <property name="username" value="root"/>
                    <property name="password" value="123456" />
                </dataSource>
    
            </environment>
    
        </environments>
       
       
        <mappers>
            <mapper resource="mapper/userMapper.xml"/>
        </mappers>
    
    </configuration>

# 第六步创建与数据库中表一致的的实体类 navicat 进行数据库的创建 #

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命令

CREATE DATABASE gxftest;  
USE gxftest;  
CREATE TABLE t\_user(  
uid INT PRIMARY KEY AUTO\_INCREMENT,  
username VARCHAR(100),  
password VARCHAR(100)  
);

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# 第七步创建数据库增删改查功能和mybatis的映射关系 #

7.1现创建mapper.xml文件

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7.2在mybatis核心配置文件中映射mapper文件

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到此关联已建立下面就是代码进行数据库的增删改查

# 第一步打开数据库通道 #

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第二步封装测试基本类

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最后编写测试类

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原创代码demo已上传

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