MyBatis Generator 生成代码

于 2020-08-17 17:22:17 发布
阅读量507 收藏
点赞数
版权声明：本文为博主原创文章，遵循 CC 4.0 BY-SA 版权协议，转载请附上原文出处链接和本声明。
本文链接：https://blog.csdn.net/fjxcsdn/article/details/108059640
版权

MyBatis Generator（MBG）是MyBatis MyBatis 和 iBATIS的代码生成器。它将为所有版本的MyBatis以及版本2.2.0之后的iBATIS版本生成代码。它将内省数据库表（或许多表），并将生成可用于访问表的工件。这减少了设置对象和配置文件以与数据库表交互的初始麻烦。MBG寻求对简单CRUD（创建，检索，更新，删除）的大部分数据库操作产生重大影响。您仍然需要为连接查询或存储过程手动编写SQL和对象代码。

创建 maven 项目

在这里插入图片描述

pom文件
<?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.fjx.coder</groupId>
    <artifactId>coder</artifactId>
    <version>1.0.0-SNAPSHOT</version>

    <dependencies>
        <dependency>
            <groupId>org.mybatis.generator</groupId>
            <artifactId>mybatis-generator-core</artifactId>
            <version>1.3.7</version>
        </dependency>
    </dependencies>


    <build>
        <plugins>
            <plugin>
                <groupId>org.mybatis.generator</groupId>
                <artifactId>mybatis-generator-maven-plugin</artifactId>
                <version>1.3.7</version>
                <dependencies>
                    <dependency>
                        <groupId>mysql</groupId>
                        <artifactId>mysql-connector-java</artifactId>
                        <version>5.1.31</version>
                    </dependency>
                </dependencies>
                <configuration>
                    <overwrite>true</overwrite>
                    <outputDirectory>${project.build.directory}</outputDirectory>
                    <verbose>true</verbose>
                    <tableNames>%</tableNames>
                </configuration>
            </plugin>
        </plugins>
    </build>
</project>

generatorConfig.xml 文件

<?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>
    <context id="MysqlContext" targetRuntime="MyBatis3" defaultModelType="flat">
        <property name="beginningDelimiter" value="`"/>
        <property name="endingDelimiter" value="`"/>

        <!-- 指定生成的java文件的编码,没有直接生成到项目时中文可能会乱码 -->
        <property name="javaFileEncoding" value="UTF-8"/>

        <!-- 生成的pojo，将implements Serializable -->
        <plugin type="org.mybatis.generator.plugins.SerializablePlugin"></plugin>
        <!-- 这里的type里写的是你的实现类的类全路径 -->
        <!--<commentGenerator type="com.MyCommentGenerator">-->
            <!--<property name="suppressDate" value="true"/>-->
        <!--</commentGenerator>-->

        <commentGenerator>
            <property name="suppressDate" value="true"/>
        </commentGenerator>

        <jdbcConnection driverClass="com.mysql.jdbc.Driver"
                        connectionURL="jdbc:mysql://192.168.183.137/prize?tinyInt1isBit=false"
                        userId="root"
                        password="root">
        </jdbcConnection>

<!--        <javaTypeResolver type="com.JavaTypeResolverDefaultImpl">-->
<!--        </javaTypeResolver>-->

        <!-- entity 包路径 -->
        <javaModelGenerator targetPackage="com.fjx.db.entity" targetProject="MAVEN">
            <property name="trimStrings" value="true"/>
        </javaModelGenerator>

        <!-- xml 路径-->
        <sqlMapGenerator targetPackage="com.fjx.db.xml.mapper" targetProject="MAVEN"/>

        <!-- dao路径 -->
        <!--<javaClientGenerator type="XMLMAPPER" targetPackage="com.fjx.dao1"  targetProject="MAVEN"/>-->
        <!--<javaClientGenerator type="ANNOTATEDMAPPER" targetPackage="com.fjx.dao2"  targetProject="MAVEN"/>-->
        <javaClientGenerator type="MIXEDMAPPER" targetPackage="com.fjx.db.mapper" targetProject="MAVEN"/>

        <table tableName="%">
            <generatedKey column="id" sqlStatement="Mysql" identity="true"/>
        </table>
    </context>
</generatorConfiguration>
配置文件详解

在这里插入图片描述

生成代码

在这里插入图片描述

打开项目目录

在这里插入图片描述
我们打开一个实体类发现字段类型与数据库中的不一致
在这里插入图片描述
在这里插入图片描述
此时我们需要通过 JavaTypeResolverDefaultImpl 类去声明一下，默认将 tinyint 类型的字段转化为integer。
在这里插入图片描述
JavaTypeResolverDefaultImpl

//
// Source code recreated from a .class file by IntelliJ IDEA
// (powered by Fernflower decompiler)
//

package com;

import org.mybatis.generator.api.IntrospectedColumn;
import org.mybatis.generator.api.JavaTypeResolver;
import org.mybatis.generator.api.dom.java.FullyQualifiedJavaType;
import org.mybatis.generator.config.Context;
import org.mybatis.generator.internal.util.StringUtility;

import java.math.BigDecimal;
import java.util.*;

public class JavaTypeResolverDefaultImpl implements JavaTypeResolver {
    protected List<String> warnings;
    protected Properties properties = new Properties();
    protected Context context;
    protected boolean forceBigDecimals;
    protected boolean useJSR310Types;
    protected Map<Integer, JdbcTypeInformation> typeMap = new HashMap();
    private static final int TIME_WITH_TIMEZONE = 2013;
    private static final int TIMESTAMP_WITH_TIMEZONE = 2014;

    public JavaTypeResolverDefaultImpl() {
        this.typeMap.put(2003, new JavaTypeResolverDefaultImpl.JdbcTypeInformation("ARRAY", new FullyQualifiedJavaType(Object.class.getName())));
        this.typeMap.put(-5, new JavaTypeResolverDefaultImpl.JdbcTypeInformation("BIGINT", new FullyQualifiedJavaType(Long.class.getName())));
        this.typeMap.put(-2, new JavaTypeResolverDefaultImpl.JdbcTypeInformation("BINARY", new FullyQualifiedJavaType("byte[]")));
        this.typeMap.put(-7, new JavaTypeResolverDefaultImpl.JdbcTypeInformation("BIT", new FullyQualifiedJavaType(Boolean.class.getName())));
        this.typeMap.put(2004, new JavaTypeResolverDefaultImpl.JdbcTypeInformation("BLOB", new FullyQualifiedJavaType("byte[]")));
        this.typeMap.put(16, new JavaTypeResolverDefaultImpl.JdbcTypeInformation("BOOLEAN", new FullyQualifiedJavaType(Boolean.class.getName())));
        this.typeMap.put(1, new JavaTypeResolverDefaultImpl.JdbcTypeInformation("CHAR", new FullyQualifiedJavaType(String.class.getName())));
        this.typeMap.put(2005, new JavaTypeResolverDefaultImpl.JdbcTypeInformation("CLOB", new FullyQualifiedJavaType(String.class.getName())));
        this.typeMap.put(70, new JavaTypeResolverDefaultImpl.JdbcTypeInformation("DATALINK", new FullyQualifiedJavaType(Object.class.getName())));
        this.typeMap.put(91, new JavaTypeResolverDefaultImpl.JdbcTypeInformation("DATE", new FullyQualifiedJavaType(Date.class.getName())));
        this.typeMap.put(3, new JavaTypeResolverDefaultImpl.JdbcTypeInformation("DECIMAL", new FullyQualifiedJavaType(BigDecimal.class.getName())));
        this.typeMap.put(2001, new JavaTypeResolverDefaultImpl.JdbcTypeInformation("DISTINCT", new FullyQualifiedJavaType(Object.class.getName())));
        this.typeMap.put(8, new JavaTypeResolverDefaultImpl.JdbcTypeInformation("DOUBLE", new FullyQualifiedJavaType(Double.class.getName())));
        this.typeMap.put(6, new JavaTypeResolverDefaultImpl.JdbcTypeInformation("FLOAT", new FullyQualifiedJavaType(Double.class.getName())));
        this.typeMap.put(4, new JavaTypeResolverDefaultImpl.JdbcTypeInformation("INTEGER", new FullyQualifiedJavaType(Integer.class.getName())));
        this.typeMap.put(2000, new JavaTypeResolverDefaultImpl.JdbcTypeInformation("JAVA_OBJECT", new FullyQualifiedJavaType(Object.class.getName())));
        this.typeMap.put(-16, new JavaTypeResolverDefaultImpl.JdbcTypeInformation("LONGNVARCHAR", new FullyQualifiedJavaType(String.class.getName())));
        this.typeMap.put(-4, new JavaTypeResolverDefaultImpl.JdbcTypeInformation("LONGVARBINARY", new FullyQualifiedJavaType("byte[]")));
        this.typeMap.put(-1, new JavaTypeResolverDefaultImpl.JdbcTypeInformation("LONGVARCHAR", new FullyQualifiedJavaType(String.class.getName())));
        this.typeMap.put(-15, new JavaTypeResolverDefaultImpl.JdbcTypeInformation("NCHAR", new FullyQualifiedJavaType(String.class.getName())));
        this.typeMap.put(2011, new JavaTypeResolverDefaultImpl.JdbcTypeInformation("NCLOB", new FullyQualifiedJavaType(String.class.getName())));
        this.typeMap.put(-9, new JavaTypeResolverDefaultImpl.JdbcTypeInformation("NVARCHAR", new FullyQualifiedJavaType(String.class.getName())));
        this.typeMap.put(0, new JavaTypeResolverDefaultImpl.JdbcTypeInformation("NULL", new FullyQualifiedJavaType(Object.class.getName())));
        this.typeMap.put(2, new JavaTypeResolverDefaultImpl.JdbcTypeInformation("NUMERIC", new FullyQualifiedJavaType(BigDecimal.class.getName())));
        this.typeMap.put(1111, new JavaTypeResolverDefaultImpl.JdbcTypeInformation("OTHER", new FullyQualifiedJavaType(Object.class.getName())));
        this.typeMap.put(7, new JavaTypeResolverDefaultImpl.JdbcTypeInformation("REAL", new FullyQualifiedJavaType(Float.class.getName())));
        this.typeMap.put(2006, new JavaTypeResolverDefaultImpl.JdbcTypeInformation("REF", new FullyQualifiedJavaType(Object.class.getName())));
        this.typeMap.put(5, new JavaTypeResolverDefaultImpl.JdbcTypeInformation("SMALLINT", new FullyQualifiedJavaType(Integer.class.getName())));
        this.typeMap.put(2002, new JavaTypeResolverDefaultImpl.JdbcTypeInformation("STRUCT", new FullyQualifiedJavaType(Object.class.getName())));
        this.typeMap.put(92, new JavaTypeResolverDefaultImpl.JdbcTypeInformation("TIME", new FullyQualifiedJavaType(Date.class.getName())));
        this.typeMap.put(93, new JavaTypeResolverDefaultImpl.JdbcTypeInformation("TIMESTAMP", new FullyQualifiedJavaType(Date.class.getName())));
        this.typeMap.put(-6, new JavaTypeResolverDefaultImpl.JdbcTypeInformation("TINYINT", new FullyQualifiedJavaType(Integer.class.getName())));
        this.typeMap.put(-3, new JavaTypeResolverDefaultImpl.JdbcTypeInformation("VARBINARY", new FullyQualifiedJavaType("byte[]")));
        this.typeMap.put(12, new JavaTypeResolverDefaultImpl.JdbcTypeInformation("VARCHAR", new FullyQualifiedJavaType(String.class.getName())));
        this.typeMap.put(2013, new JavaTypeResolverDefaultImpl.JdbcTypeInformation("TIME_WITH_TIMEZONE", new FullyQualifiedJavaType("java.time.OffsetTime")));
        this.typeMap.put(2014, new JavaTypeResolverDefaultImpl.JdbcTypeInformation("TIMESTAMP_WITH_TIMEZONE", new FullyQualifiedJavaType("java.time.OffsetDateTime")));
    }

    public void addConfigurationProperties(Properties properties) {
        this.properties.putAll(properties);
        this.forceBigDecimals = StringUtility.isTrue(properties.getProperty("forceBigDecimals"));
        this.useJSR310Types = StringUtility.isTrue(properties.getProperty("useJSR310Types"));
    }

    public FullyQualifiedJavaType calculateJavaType(IntrospectedColumn introspectedColumn) {
        FullyQualifiedJavaType answer = null;
        JavaTypeResolverDefaultImpl.JdbcTypeInformation jdbcTypeInformation = (JavaTypeResolverDefaultImpl.JdbcTypeInformation)this.typeMap.get(introspectedColumn.getJdbcType());
        if (jdbcTypeInformation != null) {
            answer = jdbcTypeInformation.getFullyQualifiedJavaType();
            answer = this.overrideDefaultType(introspectedColumn, answer);
        }

        return answer;
    }

    protected FullyQualifiedJavaType overrideDefaultType(IntrospectedColumn column, FullyQualifiedJavaType defaultType) {
        FullyQualifiedJavaType answer = defaultType;
        switch(column.getJdbcType()) {
        case -7:
            answer = this.calculateBitReplacement(column, defaultType);
            break;
        case 2:
        case 3:
            answer = this.calculateBigDecimalReplacement(column, defaultType);
            break;
        case 91:
            answer = this.calculateDateType(column, defaultType);
            break;
        case 92:
            answer = this.calculateTimeType(column, defaultType);
            break;
        case 93:
            answer = this.calculateTimestampType(column, defaultType);
        }

        return answer;
    }

    protected FullyQualifiedJavaType calculateDateType(IntrospectedColumn column, FullyQualifiedJavaType defaultType) {
        FullyQualifiedJavaType answer;
        if (this.useJSR310Types) {
            answer = new FullyQualifiedJavaType("java.time.LocalDate");
        } else {
            answer = defaultType;
        }

        return answer;
    }

    protected FullyQualifiedJavaType calculateTimeType(IntrospectedColumn column, FullyQualifiedJavaType defaultType) {
        FullyQualifiedJavaType answer;
        if (this.useJSR310Types) {
            answer = new FullyQualifiedJavaType("java.time.LocalTime");
        } else {
            answer = defaultType;
        }

        return answer;
    }

    protected FullyQualifiedJavaType calculateTimestampType(IntrospectedColumn column, FullyQualifiedJavaType defaultType) {
        FullyQualifiedJavaType answer;
        if (this.useJSR310Types) {
            answer = new FullyQualifiedJavaType("java.time.LocalDateTime");
        } else {
            answer = defaultType;
        }

        return answer;
    }

    protected FullyQualifiedJavaType calculateBitReplacement(IntrospectedColumn column, FullyQualifiedJavaType defaultType) {
        FullyQualifiedJavaType answer;
        if (column.getLength() > 1) {
            answer = new FullyQualifiedJavaType("byte[]");
        } else {
            answer = defaultType;
        }

        return answer;
    }

    protected FullyQualifiedJavaType calculateBigDecimalReplacement(IntrospectedColumn column, FullyQualifiedJavaType defaultType) {
        FullyQualifiedJavaType answer;
        if (column.getScale() <= 0 && column.getLength() <= 18 && !this.forceBigDecimals) {
            if (column.getLength() > 9) {
                answer = new FullyQualifiedJavaType(Long.class.getName());
            } else if (column.getLength() > 4) {
                answer = new FullyQualifiedJavaType(Integer.class.getName());
            } else {
                answer = new FullyQualifiedJavaType(Short.class.getName());
            }
        } else {
            answer = defaultType;
        }

        return answer;
    }

    public String calculateJdbcTypeName(IntrospectedColumn introspectedColumn) {
        String answer = null;
        JavaTypeResolverDefaultImpl.JdbcTypeInformation jdbcTypeInformation = (JavaTypeResolverDefaultImpl.JdbcTypeInformation)this.typeMap.get(introspectedColumn.getJdbcType());
        if (jdbcTypeInformation != null) {
            answer = jdbcTypeInformation.getJdbcTypeName();
        }

        return answer;
    }

    public void setWarnings(List<String> warnings) {
        this.warnings = warnings;
    }

    public void setContext(Context context) {
        this.context = context;
    }

    public static class JdbcTypeInformation {
        private String jdbcTypeName;
        private FullyQualifiedJavaType fullyQualifiedJavaType;

        public JdbcTypeInformation(String jdbcTypeName, FullyQualifiedJavaType fullyQualifiedJavaType) {
            this.jdbcTypeName = jdbcTypeName;
            this.fullyQualifiedJavaType = fullyQualifiedJavaType;
        }

        public String getJdbcTypeName() {
            return this.jdbcTypeName;
        }

        public FullyQualifiedJavaType getFullyQualifiedJavaType() {
            return this.fullyQualifiedJavaType;
        }
    }
}

此时需要在配置文件中通过javaTypeResolver 标签指定
在这里插入图片描述
pom文件指定 JavaTypeResolverDefaultImpl 所在的模块的依赖
在这里插入图片描述
重新生成代码
在这里插入图片描述

MyCommentGenerator

package com;

import org.mybatis.generator.api.IntrospectedColumn;
import org.mybatis.generator.api.IntrospectedTable;
import org.mybatis.generator.api.dom.java.CompilationUnit;
import org.mybatis.generator.api.dom.java.Field;
import org.mybatis.generator.api.dom.java.JavaElement;
import org.mybatis.generator.api.dom.xml.XmlElement;
import org.mybatis.generator.config.MergeConstants;
import org.mybatis.generator.internal.DefaultCommentGenerator;

/**
 * mybatis generator 自定义comment生成器.
 * 基于MBG 1.3.2. 
 *
 */
public class MyCommentGenerator extends DefaultCommentGenerator {

    public MyCommentGenerator() {
        super();
    }

    public void addJavaFileComment(CompilationUnit compilationUnit) {
        // add no file level comments by default
        return;
    }

    /**
     * Adds a suitable comment to warn users that the element was generated, and
     * when it was generated.
     */
    public void addComment(XmlElement xmlElement) {
        return;
    }

    public void addRootComment(XmlElement rootElement) {
        // add no document level comments by default
        return;
    }


    /**
     * This method adds the custom javadoc tag for. You may do nothing if you do
     * not wish to include the Javadoc tag - however, if you do not include the
     * Javadoc tag then the Java merge capability of the eclipse plugin will
     * break.
     *
     * @param javaElement the java element
     */
    protected void addJavadocTag(JavaElement javaElement, boolean markAsDoNotDelete) {
        javaElement.addJavaDocLine(" *");
        StringBuilder sb = new StringBuilder();
        sb.append(" * ");
        sb.append(MergeConstants.NEW_ELEMENT_TAG);
        if (markAsDoNotDelete) {
            sb.append(" do_not_delete_during_merge");
        }
        String s = getDateString();
        if (s != null) {
            sb.append(' ');
            sb.append(s);
        }
        javaElement.addJavaDocLine(sb.toString());
    }



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

        StringBuilder sb = new StringBuilder();

        field.addJavaDocLine("/**");
        sb.append(" * ");
        sb.append(introspectedColumn.getRemarks());
        field.addJavaDocLine(sb.toString());

        //      addJavadocTag(field, false);

        field.addJavaDocLine(" */");
    }

    public void addFieldComment(Field field, IntrospectedTable introspectedTable) {

        StringBuilder sb = new StringBuilder();

        field.addJavaDocLine("/**");
        sb.append(" * ");
        sb.append(introspectedTable.getFullyQualifiedTable());
        field.addJavaDocLine(sb.toString());
        field.addJavaDocLine(" */");
    }

}
冯佳兴
关注
评论
添加红包

请填写红包祝福语或标题

个

红包个数最小为10个

元

红包金额最低5元

当前余额3.43元 前往充值 >
需支付：10.00元
成就一亿技术人!
领取后你会自动成为博主和红包主的粉丝 规则
hope_wisdom
发出的红包
实付元
使用余额支付
点击重新获取
扫码支付
钱包余额 0

抵扣说明：

1.余额是钱包充值的虚拟货币，按照1:1的比例进行支付金额的抵扣。
2.余额无法直接购买下载，可以购买VIP、付费专栏及课程。

余额充值