IDEA创建SpringBoot项目使用JDK1.8

由于现在还有大量项目使用的jdk版本是1.8，所以今天记录下IDEA创建JDK1.8版本SpringBoot项目的记录。

1 点new Project，新建项目

2 左边选择SpringInitalizr，右边名字路径随意，类型选maven，jdk我这只能选17，后边改

3 我先选择了这几个功能，日志用lombok，还有web，数据库里边的jdbc，mysql，mybatis。登录鉴权相关的SpringSecurity。

4 如果此时你不需要改jdk版本，点击create等待项目自动加载，就算完成了。

5 下面开始改jdk版本，把根目录下pom.xml 文件换成我这个版本

<?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 https://maven.apache.org/xsd/maven-4.0.0.xsd">
    <modelVersion>4.0.0</modelVersion>
    <parent>
            <groupId>org.springframework.boot</groupId>
            <artifactId>spring-boot-starter-parent</artifactId>
            <version>2.7.10</version> <!-- &#9989; 支持 Java 8 的最后稳定版 -->
            <relativePath/>
    </parent>
    <groupId>com.example</groupId>
    <artifactId>springDemo</artifactId>
    <version>0.0.1-SNAPSHOT</version>
    <name>springDemo</name>
    <description>springDemo</description>
    <url/>
    <licenses>
        <license/>
    </licenses>
    <developers>
        <developer/>
    </developers>
    <scm>
        <connection/>
        <developerConnection/>
        <tag/>
        <url/>
    </scm>
    <properties>
        <java.version>8</java.version>
    </properties>
    <dependencies>
        <!-- 替换 MyBatis Starter -->
        <dependency>
            <groupId>org.mybatis.spring.boot</groupId>
            <artifactId>mybatis-spring-boot-starter</artifactId>
            <version>2.2.0</version> <!-- &#9989; 支持 Java 8 -->
        </dependency>

        <dependency>
            <groupId>org.mybatis.spring.boot</groupId>
            <artifactId>mybatis-spring-boot-starter-test</artifactId>
            <version>2.2.0</version>
            <scope>test</scope>
        </dependency>

        <!-- 替换测试框架为 JUnit 4 -->
        <dependency>
            <groupId>junit</groupId>
            <artifactId>junit</artifactId>
            <scope>test</scope>
            <version>4.13.2</version>
        </dependency>
        <!-- JUnit Jupiter Engine（实现层） -->
        <dependency>
            <groupId>org.junit.jupiter</groupId>
            <artifactId>junit-jupiter-engine</artifactId>
            <scope>test</scope>
        </dependency>
        <dependency>
            <groupId>org.springframework.boot</groupId>
            <artifactId>spring-boot-starter-data-jpa</artifactId>
        </dependency>
        <dependency>
            <groupId>org.springframework.boot</groupId>
            <artifactId>spring-boot-starter-jdbc</artifactId>
        </dependency>
        <dependency>
            <groupId>org.springframework.boot</groupId>
            <artifactId>spring-boot-starter-security</artifactId>
        </dependency>
        <dependency>
            <groupId>org.springframework.security</groupId>
            <artifactId>spring-security-test</artifactId>
            <scope>test</scope>
        </dependency>
        <dependency>
            <groupId>org.springframework.boot</groupId>
            <artifactId>spring-boot-starter-web</artifactId>
        </dependency>
        <dependency>
            <groupId>com.mysql</groupId>
            <artifactId>mysql-connector-j</artifactId>
            <scope>runtime</scope>
        </dependency>
        <dependency>
            <groupId>org.projectlombok</groupId>
            <artifactId>lombok</artifactId>
            <optional>true</optional>
        </dependency>
        <dependency>
            <groupId>org.springframework.boot</groupId>
            <artifactId>spring-boot-starter-test</artifactId>
            <scope>test</scope>
        </dependency>
    </dependencies>

    <build>
        <plugins>
            <plugin>
                <groupId>org.apache.maven.plugins</groupId>
                <artifactId>maven-compiler-plugin</artifactId>
                <configuration>
                    <source>${java.version}</source>       <!-- 使用 properties 中定义的版本 -->
                    <target>${java.version}</target>
                    <fork>true</fork>                     <!-- 确保独立进程编译避免干扰 -->
                </configuration>
            </plugin>

            <plugin>
                <groupId>org.apache.maven.plugins</groupId>
                <artifactId>maven-compiler-plugin</artifactId>
                <configuration>
                    <annotationProcessorPaths>
                        <path>
                            <groupId>org.projectlombok</groupId>
                            <artifactId>lombok</artifactId>
                            <version>1.18.26</version>
                        </path>
                    </annotationProcessorPaths>
                </configuration>
            </plugin>
            <plugin>
                <groupId>org.springframework.boot</groupId>
                <artifactId>spring-boot-maven-plugin</artifactId>
                <configuration>
                </configuration>
            </plugin>
        </plugins>
    </build>

</project>

记得maven reload一下

6 进入项目设置.把能换成1.8的都换

7 修改jdbc配置，得准备个数据库，本地或远程能访问的。在resource下增加application.yml 配置文件。

文件内容如下，我是本地mysql，本地安装mysql，可以搜索相关安装步骤。有时间我也出一期。

server:
  port : 8081

spring:
  datasource:
    name : test
    url : jdbc:mysql://localhost:3306/spring_demo?characterEncoding=utf8&allowPublicKeyRetrieval=true&useSSL=false&serverTimezone=UTC&rewriteBatchedStatements=true
    username : root
    password: root
    driver-class-name: com.mysql.cj.jdbc.Driver
mybatis:
  config-location: classpath:mybatis-config.xml

8 在下面再增加mybatis-config.xml 文件

<?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>
    <settings>
        <!-- Globally enables or disables any caches configured in any mapper under this configuration -->
        <setting name="cacheEnabled" value="true"/>
        <!-- Sets the number of seconds the driver will wait for a response from the database -->
        <setting name="defaultStatementTimeout" value="3000"/>
        <!-- Enables automatic mapping from classic database column names A_COLUMN to camel case classic Java property names aColumn -->
        <setting name="mapUnderscoreToCamelCase" value="true"/>
        <!-- Allows JDBC support for generated keys. A compatible driver is required.
        This setting forces generated keys to be used if set to true,
         as some drivers deny compatibility but still work -->
        <setting name="useGeneratedKeys" value="true"/>
    </settings>
    <!-- Continue going here -->
</configuration>

9 运行项目看能否启动起来

当显示这一行，就证明启动成功了