Mybatis --- mybatis-generator組件

初衷

玩掘金應該有一段時間了吧,可是歷來沒有在上面寫過任何東西.以前有維護過一個我的博客,原本想繼續更新,但每逢遷移,前先後後不少事情,本身感受比較麻煩,乾脆之後就來這裏筆記本身的思考和學習吧.

爲何要學習mybatis-generator

官方已經提供了咱們比較好用的mybatis-generator插件,why咱們還要折騰?我思考了下得出瞭如下三個緣由:

1. 企業開發中咱們每每須要更方便,更快速的工具
2. 提高自我對mybatis的學習,豐富自我裝裝逼,哈哈^^

本文重點

1.將mybatis-generator 集成到maven中 2.自定義生成器,生成實體的註釋(原生的註釋太囉嗦)

環境

1.spring-boot-2.1.1.RELEASE

2.mybatis-generator-1.3.5

封裝本身的mybatis-generator插件(打成公共jar包的方式)

1.建立Spring Maven項目,添加Pom依賴

<dependency>
    <groupId>org.mybatis.generator</groupId>
    <artifactId>mybatis-generator-core</artifactId>
    <version>1.3.5</version>
</dependency>
複製代碼

2.由於咱們是以公共jar的方式提供generator插件, 因此刪除Spring-Boot啓動類,同時Pom中添加 Maven打包插件

<plugins>
    <plugin>
        <groupId>org.apache.maven.plugins</groupId>
        <artifactId>maven-compiler-plugin</artifactId>
        <version>2.0.2</version>
        <configuration>
            <source>1.8</source>
            <target>1.8</target>
            <encoding>UTF-8</encoding>
        </configuration>
    </plugin>

    <plugin>
        <groupId>org.apache.maven.plugins</groupId>
        <artifactId>maven-source-plugin</artifactId>
        <version>2.2.1</version>
        <executions>
            <execution>
                <id>attach-source</id>
                <goals>
                    <goal>jar</goal>
                </goals>
            </execution>
        </executions>
    </plugin>
</plugins>
複製代碼

3.由於咱們是以jar包的形式被引入其餘項目,因此pom中能夠配置私服,deploy到私服.至於私服怎麼搭建這裏就再也不累贅,這裏就以本地搭建的私服爲例

<distributionManagement>
    <repository>
        <id>ov-release</id>
        <name>Release Repository of ov</name>
        <url>http://localhost:8081/repository/ov-release/</url>
    </repository>
    <snapshotRepository>
        <id>ov-snapshot</id>
        <name>Snapshot Repository of ov</name>
        <url>http://localhost:8081/repository/ov-snapshot/</url>
    </snapshotRepository>
</distributionManagement>
複製代碼

4.實現本身的CommentGenerator 查看mybatis-generator的源碼會發現,咱們生成實體的註釋都是經過CommentGenerator接口來作的,而框架已經爲咱們提供了默認的也就是DefaultCommentGenerator(註釋不滿意), 因爲咱們對框架默認產生的註釋不滿意, 因此接下來咱們實現本身的CommentGenerator(由以上分析咱們能夠extends DefaultCommentGenerator || implements CommentGenerator), 這裏咱們就採用實現的方式吧

5.定義CommentGeneratorAdaptor實現: 做爲適配空實現CommentGenerator

public class CommentGeneratorAdaptor implements CommentGenerator {
    @Override
    public void addConfigurationProperties(Properties properties) {

    }

    @Override
    public void addFieldComment(Field field, IntrospectedTable introspectedTable, IntrospectedColumn introspectedColumn) {

    }

    @Override
    public void addFieldComment(Field field, IntrospectedTable introspectedTable) {

    }

    @Override
    public void addModelClassComment(TopLevelClass topLevelClass, IntrospectedTable introspectedTable) {

    }

    @Override
    public void addClassComment(InnerClass innerClass, IntrospectedTable introspectedTable) {

    }

    @Override
    public void addClassComment(InnerClass innerClass, IntrospectedTable introspectedTable, boolean b) {

    }

    @Override
    public void addEnumComment(InnerEnum innerEnum, IntrospectedTable introspectedTable) {

    }

    @Override
    public void addGetterComment(Method method, IntrospectedTable introspectedTable, IntrospectedColumn introspectedColumn) {

    }

    @Override
    public void addSetterComment(Method method, IntrospectedTable introspectedTable, IntrospectedColumn introspectedColumn) {

    }

    @Override
    public void addGeneralMethodComment(Method method, IntrospectedTable introspectedTable) {

    }

    @Override
    public void addJavaFileComment(CompilationUnit compilationUnit) {

    }

    @Override
    public void addComment(XmlElement xmlElement) {

    }

    @Override
    public void addRootComment(XmlElement xmlElement) {

    }
}
複製代碼

6.定義CommentGeneratorWrapper實現

public class CommentGeneratorWrapper extends CommentGeneratorAdaptor {

    private Properties properties;

    public CommentGeneratorWrapper() {
        properties = new Properties();
    }

    @Override
    public void addConfigurationProperties(Properties properties) {
        // 獲取自定義的 properties
        this.properties.putAll(properties);
    }

    @Override
    public void addModelClassComment(TopLevelClass topLevelClass, IntrospectedTable introspectedTable) {
        String author = properties.getProperty("author");
        String dateFormat = properties.getProperty("dateFormat", "yyyy-MM-dd");
        SimpleDateFormat dateFormatter = new SimpleDateFormat(dateFormat);

        // 獲取表註釋
        String remarks = introspectedTable.getRemarks();

        topLevelClass.addJavaDocLine("/**");
        topLevelClass.addJavaDocLine(" * " + remarks);
        topLevelClass.addJavaDocLine(" *");
        topLevelClass.addJavaDocLine(" * @author " + author);
        topLevelClass.addJavaDocLine(" *");
        topLevelClass.addJavaDocLine(" * @date " + dateFormatter.format(new Date()));
        topLevelClass.addJavaDocLine(" */");
    }

    @Override
    public void addFieldComment(Field field, IntrospectedTable introspectedTable, IntrospectedColumn introspectedColumn) {
        // 獲取列註釋
        String remarks = introspectedColumn.getRemarks();
        field.addJavaDocLine("/** " + remarks + " */");
    }
}
複製代碼

7.打包,發佈到私服

mvn clean install deploy
複製代碼

項目使用

此時咱們就能夠在業務項目中使用咱們剛纔打包的mybatis-generator了, 對了,忘記說明一點,在此以前咱們打成的generator maven座標爲:

<dependency>
    <groupId>com.github.ov</groupId>
    <artifactId>generator</artifactId>
    <version>0.0.1-SNAPSHOT</version>
</dependency>
複製代碼

1.咱們在業務項目中引入座標

<dependency>
    <groupId>com.github.ov</groupId>
    <artifactId>generator</artifactId>
    <version>0.0.1-SNAPSHOT</version>
</dependency>
複製代碼

2.在Maven中配置插件以Maven的形式運行

<plugin>
    <groupId>org.mybatis.generator</groupId>
    <artifactId>mybatis-generator-maven-plugin</artifactId>
    <version>1.3.5</version>
    <dependencies>
        <dependency>
            <groupId>com.github.ov</groupId>
            <artifactId>generator</artifactId>
            <version>0.0.1-SNAPSHOT</version>
        </dependency>

        <!--connector driver jar-->
        <dependency>
            <groupId>mysql</groupId>
            <artifactId>mysql-connector-java</artifactId>
            <version>5.1.37</version>
            <scope>runtime</scope>
        </dependency>
    </dependencies>
</plugin>
複製代碼

3.在資源文件夾下面建立generatorConfig.xml

<?xml version="1.0" encoding="UTF-8"?>
<!DOCTYPE generatorConfiguration PUBLIC "-//mybatis.org//DTD MyBatis Generator Configuration 1.0//EN" "http://mybatis.org/dtd/mybatis-generator-config_1_0.dtd">

<generatorConfiguration>
    <!--指定特定數據庫的jdbc驅動jar包的位置 -->
    <!--<classPathEntry location="mysql-connector-java-5.1.37-bin.jar"/>-->

    <context id="XMBG-01" targetRuntime="MyBatis3">
        <!-- 生成的 Java 文件的編碼 -->
        <property name="javaFileEncoding" value="UTF-8"/>
        <!-- 格式化 Java 代碼 -->
        <property name="javaFormatter" value="org.mybatis.generator.api.dom.DefaultJavaFormatter"/>
        <!-- 格式化 XML 代碼 -->
        <property name="xmlFormatter" value="org.mybatis.generator.api.dom.DefaultXmlFormatter"/>

        <!-- 自定義註釋生成器 -->
        <commentGenerator type="com.github.ov.generator.CommentGeneratorWrapper">
            <property name="author" value="JOSE"/>
            <property name="dateFormat" value="yyyy-MM-dd"/>
        </commentGenerator>

        <!-- 配置數據庫鏈接 -->
        <jdbcConnection driverClass="com.mysql.jdbc.Driver" connectionURL="jdbc:mysql://ip:3306/spring_cloud?useUnicode=true&amp;characterEncoding=utf8&amp;autoReconnect=true&amp;failOverReadOnly=false&amp;useSSL=false" userId="xxx" password="xxx">
            <property name="useInformationSchema" value="true" />
        </jdbcConnection>

        <!--默認false Java type resolver will always use java.math.BigDecimal if the database column is of type DECIMAL or NUMERIC. -->
        <javaTypeResolver>
            <property name="forceBigDecimals" value="false"/>
        </javaTypeResolver>

        <!-- 生成實體的位置 -->
        <javaModelGenerator targetPackage="com.github.product.model.po" targetProject="MAVEN">
            <property name="enableSubPackages" value="true"/>
            <property name="trimStrings" value="false"/>
        </javaModelGenerator>

        <!-- 生成 Mapper 接口的位置 -->
        <sqlMapGenerator targetPackage="com.github.product.dao" targetProject="MAVEN">
            <property name="enableSubPackages" value="true"/>
        </sqlMapGenerator>

        <!-- 生成 Mapper XML 的位置 -->
        <javaClientGenerator targetPackage="com.github.product.dao" type="XMLMAPPER" targetProject="MAVEN">
            <property name="enableSubPackages" value="true"/>
        </javaClientGenerator>

        <!-- 設置數據庫的表名和實體類名 -->
        <table tableName="product_info" domainObjectName="ProductInfo" mapperName="ProductInfoDao" enableCountByExample="false" enableUpdateByExample="false" enableDeleteByExample="false" enableSelectByExample="false" selectByExampleQueryId="false">
            <generatedKey column="id" sqlStatement="JDBC" identity="true" />
        </table>
    </context>
</generatorConfiguration>
複製代碼

4.至此咱們運行generator插件 || mvn命令運行就會生成咱們的持久層類, 在target/ 目錄下,也會發現註釋是咱們數據庫的註釋

mvn mybatis-generator:generate
複製代碼

5.運行結果:

6.注意:咱們自定義的CommentGenerator已經要打成包引入,否則會找不到此類, 固然這是Maven形式運行; 固然你也能夠採用Main方法的形式運行, 只不過我感受在企業開發中這個更方便