mybatis自定义代码生成器（Generator）——自动生成model&dao代码

花了两天的时间研究了下mybatis的generator大体了解了其生成原理以及实现过程。感觉generator做的非常不错，给开发者也留足了空间。看完之后在generator的基础上实现了自定义的生成器。代码start.....

建立了一个maven工程（common）项目结构：

----------------------------------------------------------------pom.xml-----------------------------------------------------------

<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/maven-v4_0_0.xsd"><modelVersion>4.0.0</modelVersion><groupId>com.yangchao</groupId><artifactId>project-common</artifactId><version>0.0.1-SNAPSHOT</version><name>project-common Maven Webapp</name><url>http://maven.apache.org</url><dependencies><dependency><groupId>junit</groupId><artifactId>junit</artifactId><version>3.8.1</version><scope>test</scope></dependency><dependency><groupId>javax</groupId><artifactId>javaee-api</artifactId><version>7.0</version></dependency><!-- https://mvnrepository.com/artifact/org.compass-project/compass --><dependency><groupId>org.compass-project</groupId><artifactId>compass</artifactId><version>2.0.2</version></dependency><!-- https://mvnrepository.com/artifact/org.mybatis.generator/mybatis-generator-core --><dependency><groupId>org.mybatis.generator</groupId><artifactId>mybatis-generator-core</artifactId><version>1.3.2</version></dependency></dependencies></project>

-------------------------------------------------------------------jdbc.properties--------------------------------------------------------------------

jdbc.driver=com.mysql.jdbc.Driverjdbc.url=jdbc:mysql://localhost:3306/demo1jdbc.username=rootjdbc.password=rootinitialSize=0maxActive=20maxIdle=20minIdle=1maxWait=60000

--------------------------------------------------------------------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><!--加载属性文件 --><properties resource="jdbc.properties" /><context id="context1" targetRuntime="MyBatis3"><!-- 实现自定义的代码生成器plugin --><plugin type="mybatis.PaginationPlugin" /><commentGenerator><property name="suppressDate" value="true" /><!-- 是否去除自动生成的注释 true：是 ： false:否 --><property name="suppressAllComments" value="true" /></commentGenerator><!-- 数据库连接URL，用户名，密码 --><jdbcConnection driverClass="${jdbc.driver}" connectionURL="${jdbc.url}" userId="${jdbc.username}"password="${jdbc.password}" /><!--生成模型的包名和位置 --><javaModelGenerator targetPackage="common.model" targetProject="project-common/src/main/java/" /><!--映射文件的包名和位置 --><sqlMapGenerator targetPackage="common.model" targetProject="project-common/src/main/java/" /><!--DAO的包名和位置 --><javaClientGenerator targetPackage="common.dao" targetProject="project-common/src/main/java" type="XMLMAPPER" /><!--要生成哪些表 --><table tableName="%" enableSelectByExample="false" enableDeleteByExample="false"enableCountByExample="false" enableUpdateByExample="false"selectByExampleQueryId="false"><property name="rootClass" value="common.BaseEntity" /></table></context></generatorConfiguration>

-------------------------------------------------------PaginationPlugin.java------------------------------------------------------

/** * @项目名称：project-common * @类名称：PaginationPlugin * @类描述：自定义代码生成器 * @创建人：YangChao * @作者单位：北京宝库在线网络技术有限公司 * @联系方式：[e-mail] * @创建时间：2016年9月5日 下午3:14:38 * @version 1.0.0 */public class PaginationPlugin extends PluginAdapter {/** * 生成dao */@Overridepublic boolean clientGenerated(Interface interfaze, TopLevelClass topLevelClass, IntrospectedTable introspectedTable) {FullyQualifiedJavaType fqjt = new FullyQualifiedJavaType("BaseDao<" + introspectedTable.getBaseRecordType()+ ">");FullyQualifiedJavaType imp = new FullyQualifiedJavaType("common.BaseDao");interfaze.addSuperInterface(fqjt);// 添加 extends BaseDao<User>interfaze.addImportedType(imp);// 添加import common.BaseDao;interfaze.getMethods().clear();return true;}/** * 生成实体中每个属性 */@Overridepublic boolean modelGetterMethodGenerated(Method method, TopLevelClass topLevelClass,IntrospectedColumn introspectedColumn, IntrospectedTable introspectedTable, ModelClassType modelClassType) {return true;}/** * 生成实体 */@Overridepublic boolean modelBaseRecordClassGenerated(TopLevelClass topLevelClass, IntrospectedTable introspectedTable) {addSerialVersionUID(topLevelClass, introspectedTable);return super.modelBaseRecordClassGenerated(topLevelClass, introspectedTable);}/** * 生成mapping */@Overridepublic boolean sqlMapGenerated(GeneratedXmlFile sqlMap, IntrospectedTable introspectedTable) {return super.sqlMapGenerated(sqlMap, introspectedTable);}/** * 生成mapping 添加自定义sql */@Overridepublic boolean sqlMapDocumentGenerated(Document document, IntrospectedTable introspectedTable) {String tableName = introspectedTable.getAliasedFullyQualifiedTableNameAtRuntime();// 数据库表名List<IntrospectedColumn> columns = introspectedTable.getAllColumns();XmlElement parentElement = document.getRootElement();// 添加sql——whereXmlElement sql = new XmlElement("sql");sql.addAttribute(new Attribute("id", "sql_where"));XmlElement where = new XmlElement("where");StringBuilder sb = new StringBuilder();for (IntrospectedColumn introspectedColumn : introspectedTable.getNonPrimaryKeyColumns()) {            XmlElement isNotNullElement = new XmlElement("if"); //$NON-NLS-1$            sb.setLength(0);            sb.append(introspectedColumn.getJavaProperty());            sb.append(" != null"); //$NON-NLS-1$            isNotNullElement.addAttribute(new Attribute("test", sb.toString())); //$NON-NLS-1$            where.addElement(isNotNullElement);            sb.setLength(0);            sb.append(" and ");            sb.append(MyBatis3FormattingUtilities.getEscapedColumnName(introspectedColumn));            sb.append(" = "); //$NON-NLS-1$            sb.append(MyBatis3FormattingUtilities.getParameterClause(introspectedColumn));            isNotNullElement.addElement(new TextElement(sb.toString()));        }sql.addElement(where);parentElement.addElement(sql);//添加getListXmlElement select = new XmlElement("select");select.addAttribute(new Attribute("id", "getList"));select.addAttribute(new Attribute("resultMap", "BaseResultMap"));select.addAttribute(new Attribute("parameterType", introspectedTable.getBaseRecordType()));select.addElement(new TextElement(" select * from "+ introspectedTable.getFullyQualifiedTableNameAtRuntime()));XmlElement include = new XmlElement("include");include.addAttribute(new Attribute("refid", "sql_where"));select.addElement(include);parentElement.addElement(select);return super.sqlMapDocumentGenerated(document, introspectedTable);}@Overridepublic boolean sqlMapUpdateByPrimaryKeyWithoutBLOBsElementGenerated(XmlElement element,IntrospectedTable introspectedTable) {return false;}@Overridepublic boolean sqlMapInsertElementGenerated(XmlElement element, IntrospectedTable introspectedTable) {return false;}@Overridepublic boolean sqlMapSelectByExampleWithoutBLOBsElementGenerated(XmlElement element,IntrospectedTable introspectedTable) {// LIMIT5,10; // 检索记录行 6-15//XmlElement isNotNullElement = new XmlElement("if");//$NON-NLS-1$//isNotNullElement.addAttribute(new Attribute("test", "limitStart != null and limitStart >=0"));//$NON-NLS-1$ //$NON-NLS-2$// isNotNullElement.addElement(new// TextElement("limit ${limitStart} , ${limitEnd}"));// element.addElement(isNotNullElement);// LIMIT 5;//检索前 5个记录行return super.sqlMapSelectByExampleWithoutBLOBsElementGenerated(element, introspectedTable);}/** * mapping中添加方法 */// @Overridepublic boolean sqlMapDocumentGenerated2(Document document, IntrospectedTable introspectedTable) {String tableName = introspectedTable.getAliasedFullyQualifiedTableNameAtRuntime();// 数据库表名List<IntrospectedColumn> columns = introspectedTable.getAllColumns();// 添加sqlXmlElement sql = new XmlElement("select");XmlElement parentElement = document.getRootElement();XmlElement deleteLogicByIdsElement = new XmlElement("update");deleteLogicByIdsElement.addAttribute(new Attribute("id", "deleteLogicByIds"));deleteLogicByIdsElement.addElement(new TextElement("update "+ tableName+ " set deleteFlag = #{deleteFlag,jdbcType=INTEGER} where id in "+ " <foreach item=\"item\" index=\"index\" collection=\"ids\" open=\"(\" separator=\",\" close=\")\">#{item}</foreach> "));parentElement.addElement(deleteLogicByIdsElement);XmlElement queryPage = new XmlElement("select");queryPage.addAttribute(new Attribute("id", "queryPage"));queryPage.addAttribute(new Attribute("resultMap", "BaseResultMap"));queryPage.addElement(new TextElement("select "));XmlElement include = new XmlElement("include");include.addAttribute(new Attribute("refid", "Base_Column_List"));queryPage.addElement(include);queryPage.addElement(new TextElement(" from " + tableName + " ${sql}"));parentElement.addElement(queryPage);return super.sqlMapDocumentGenerated(document, introspectedTable);}private void addSerialVersionUID(TopLevelClass topLevelClass, IntrospectedTable introspectedTable) {CommentGenerator commentGenerator = context.getCommentGenerator();Field field = new Field();field.setVisibility(JavaVisibility.PRIVATE);field.setType(new FullyQualifiedJavaType("long"));field.setStatic(true);field.setFinal(true);field.setName("serialVersionUID");field.setInitializationString("1L");commentGenerator.addFieldComment(field, introspectedTable);topLevelClass.addField(field);}/* * Dao中添加方法 */private Method generateDeleteLogicByIds(Method method, IntrospectedTable introspectedTable) {Method m = new Method("deleteLogicByIds");m.setVisibility(method.getVisibility());m.setReturnType(FullyQualifiedJavaType.getIntInstance());m.addParameter(new Parameter(FullyQualifiedJavaType.getIntInstance(), "deleteFlag", "@Param(\"deleteFlag\")"));m.addParameter(new Parameter(new FullyQualifiedJavaType("Integer[]"), "ids", "@Param(\"ids\")"));context.getCommentGenerator().addGeneralMethodComment(m, introspectedTable);return m;}/* * 实体中添加属性 */private void addLimit(TopLevelClass topLevelClass, IntrospectedTable introspectedTable, String name) {CommentGenerator commentGenerator = context.getCommentGenerator();Field field = new Field();field.setVisibility(JavaVisibility.PROTECTED);field.setType(FullyQualifiedJavaType.getIntInstance());field.setName(name);field.setInitializationString("-1");commentGenerator.addFieldComment(field, introspectedTable);topLevelClass.addField(field);char c = name.charAt(0);String camel = Character.toUpperCase(c) + name.substring(1);Method method = new Method();method.setVisibility(JavaVisibility.PUBLIC);method.setName("set" + camel);method.addParameter(new Parameter(FullyQualifiedJavaType.getIntInstance(), name));method.addBodyLine("this." + name + "=" + name + ";");commentGenerator.addGeneralMethodComment(method, introspectedTable);topLevelClass.addMethod(method);method = new Method();method.setVisibility(JavaVisibility.PUBLIC);method.setReturnType(FullyQualifiedJavaType.getIntInstance());method.setName("get" + camel);method.addBodyLine("return " + name + ";");commentGenerator.addGeneralMethodComment(method, introspectedTable);topLevelClass.addMethod(method);}public boolean validate(List<String> arg0) {return true;}public static void generate() {String config = PaginationPlugin.class.getClassLoader().getResource("mybatisConfig.xml").getFile();String[] arg = { "-configfile", config, "-overwrite" };ShellRunner.main(arg);}public static void main(String[] args) {generate();}}

------------------------------------------------BaseDao.java--------------------------------------------

/** * @项目名称：project-common * @类名称：BaseDao * @类描述： * @创建人：YangChao * @作者单位：北京宝库在线网络技术有限公司 * @联系方式：[e-mail] * @创建时间：2016年9月5日 下午2:51:19 * @version 1.0.0 */public interface BaseDao<T> {public T selectByPrimaryKey(Integer id);public int deleteByPrimaryKey(Integer id);public int insertSelective(T t);public int updateByPrimaryKeySelective(T t);public List<T> getList(T t);// 获取数量public int getCountSelective(T t);/** *  * @Title: findPage * @Description: TODO() * @param page *            分页参数 * @param sql *            mybatis sql语句 * @param values *            命名参数,按名称绑定 * @return 分页查询结果, 附带结果列表及所有查询时的参数. * @author YangChao * @date 2016年9月7日 下午5:30:28 */public PageView<T> findPage(final PageView<T> page, final String sql, final Map<String, Object> values);}

-------------------------------------------------BaseEntity.java---------------------------------------------------

/** * @项目名称：project-common * @类名称：BaseEntity * @类描述：所有实体类的父类。可将公共的属性所有类序列化集中在此类中 * @创建人：YangChao * @作者单位：北京宝库在线网络技术有限公司 * @联系方式：[e-mail] * @创建时间：2016年9月5日 上午11:37:02 * @version 1.0.0 */public abstract class BaseEntity implements Serializable {private static final long serialVersionUID = 1L;private Integer id;public Integer getId() {return id;}public void setId(Integer id) {this.id = id;}}

---------------------------------------------------------------------------------最终生成dao&&model------------------------------------------------------------------------------------------------

--dao--

UserMapper.java:

package common.dao;import common.BaseDao;import common.model.User;public interface UserMapper extends BaseDao<User> {}

---model---

User.java

package common.model;import common.BaseEntity;public class User extends BaseEntity {    private Integer accountId;    private String loginname;    private String password;    private Integer status;    private static final long serialVersionUID = 1L;    public Integer getAccountId() {        return accountId;    }    public void setAccountId(Integer accountId) {        this.accountId = accountId;    }    public String getLoginname() {        return loginname;    }    public void setLoginname(String loginname) {        this.loginname = loginname;    }    public String getPassword() {        return password;    }    public void setPassword(String password) {        this.password = password;    }    public Integer getStatus() {        return status;    }    public void setStatus(Integer status) {        this.status = status;    }}

UserMapper.xml

<?xml version="1.0" encoding="UTF-8" ?><!DOCTYPE mapper PUBLIC "-//mybatis.org//DTD Mapper 3.0//EN" "http://mybatis.org/dtd/mybatis-3-mapper.dtd" ><mapper namespace="common.dao.UserMapper" >  <resultMap id="BaseResultMap" type="common.model.User" >    <id column="id" property="id" jdbcType="INTEGER" />    <result column="account_id" property="accountId" jdbcType="INTEGER" />    <result column="loginname" property="loginname" jdbcType="VARCHAR" />    <result column="password" property="password" jdbcType="VARCHAR" />    <result column="status" property="status" jdbcType="INTEGER" />  </resultMap>  <sql id="Base_Column_List" >    id, account_id, loginname, password, status  </sql>  <select id="selectByPrimaryKey" resultMap="BaseResultMap" parameterType="java.lang.Integer" >    select     <include refid="Base_Column_List" />    from user    where id = #{id,jdbcType=INTEGER}  </select>  <delete id="deleteByPrimaryKey" parameterType="java.lang.Integer" >    delete from user    where id = #{id,jdbcType=INTEGER}  </delete>  <insert id="insertSelective" parameterType="common.model.User" >    insert into user    <trim prefix="(" suffix=")" suffixOverrides="," >      <if test="id != null" >        id,      </if>      <if test="accountId != null" >        account_id,      </if>      <if test="loginname != null" >        loginname,      </if>      <if test="password != null" >        password,      </if>      <if test="status != null" >        status,      </if>    </trim>    <trim prefix="values (" suffix=")" suffixOverrides="," >      <if test="id != null" >        #{id,jdbcType=INTEGER},      </if>      <if test="accountId != null" >        #{accountId,jdbcType=INTEGER},      </if>      <if test="loginname != null" >        #{loginname,jdbcType=VARCHAR},      </if>      <if test="password != null" >        #{password,jdbcType=VARCHAR},      </if>      <if test="status != null" >        #{status,jdbcType=INTEGER},      </if>    </trim>  </insert>  <update id="updateByPrimaryKeySelective" parameterType="common.model.User" >    update user    <set >      <if test="accountId != null" >        account_id = #{accountId,jdbcType=INTEGER},      </if>      <if test="loginname != null" >        loginname = #{loginname,jdbcType=VARCHAR},      </if>      <if test="password != null" >        password = #{password,jdbcType=VARCHAR},      </if>      <if test="status != null" >        status = #{status,jdbcType=INTEGER},      </if>    </set>    where id = #{id,jdbcType=INTEGER}  </update>  <sql id="sql_where" >    <where >      <if test="accountId != null" >         and account_id = #{accountId,jdbcType=INTEGER}      </if>      <if test="loginname != null" >         and loginname = #{loginname,jdbcType=VARCHAR}      </if>      <if test="password != null" >         and password = #{password,jdbcType=VARCHAR}      </if>      <if test="status != null" >         and status = #{status,jdbcType=INTEGER}      </if>    </where>  </sql>  <select id="getList" resultMap="BaseResultMap" parameterType="common.model.User" >     select * from user    <include refid="sql_where" />  </select></mapper>

-----------------------------------代码end------------------------------------

心得：由于开始使用原始的generator生成代码存在，生成后的代码继承结构不存在，重复性代码过多。其实生成所有的代码都是可自定义的，在此我只是将dao中所有的crud方法提取出去放到BaseDao中，以方便之后在具体的dao中添加特殊的需求，让代码简单明了。