mybatis 項目設定檔執行個體詳解,mybatis設定檔
mybatis項目配置
首先這事一個簡單的mybatis項目設定檔:
<?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="development"> <environment id="development"> <transactionManager type="JDBC"/> <dataSource type="POOLED"> <property name="driver" value="${driver}"/> <property name="url" value="${url}"/> <property name="username" value="${username}"/> <property name="password" value="${password}"/> </dataSource> </environment> </environments> <mappers> <mapper resource="org/mybatis/example/BlogMapper.xml"/> </mappers></configuration>
environment
mybatis支援多個環境,可以任意配置
比如:
<environments default="development"> <environment id="development"> <transactionManager type="JDBC"/> <dataSource type="POOLED"> <property name="driver" value="${driver}"/> <property name="url" value="${url}"/> <property name="username" value="${username}"/> <property name="password" value="${password}"/> </dataSource> </environment> <environment id="test"> <transactionManager type="JDBC"/> <dataSource type="POOLED"> <property name="driver" value="${driver}"/> <property name="url" value="${url}"/> <property name="username" value="${username}"/> <property name="password" value="${password}"/> </dataSource> </environment> </environments>
就會有兩個環境,environments中的defalut標籤選擇哪一個,預設就是哪一個
transactionManager
mybatis支援兩種類型的交易管理員,jdbc和managed(託管)
jdbc:應用程式管理資料庫串連的生命週期
managed:由應用伺服器負責管理資料庫串連的生命週期(一般商務服務器才有此功能,如JBOSS WebLogic)
dataSource
type:用來配置資料來源,類型有:UNPOOLED、POOLED、JNDI
UNPOOLED:沒有串連池,每次資料庫操作,mybatis都會建立一個新的串連,用完後,關閉:適合小並發項目
POOLED:有串連池
JNDI:使用應用伺服器配置JNDI資料來源擷取資料庫連接
properties
配置屬性
比如:
<properties resource="org/mybatis/example/config.properties"> <property name="username" value="dev_user"/> <property name="password" value="F2Fa3!33TYyg"/></properties><dataSource type="POOLED"> <property name="driver" value="${driver}"/> <property name="url" value="${url}"/> <property name="username" value="${username}"/> <property name="password" value="${password}"/></dataSource>
typeAliases
給類的完整限定名取別名,方便使用
比如:
<typeAliases> <typeAlias alias="Author" type="domain.blog.Author"/> <typeAlias alias="Blog" type="domain.blog.Blog"/> <typeAlias alias="Comment" type="domain.blog.Comment"/> <typeAlias alias="Post" type="domain.blog.Post"/> <typeAlias alias="Section" type="domain.blog.Section"/> <typeAlias alias="Tag" type="domain.blog.Tag"/></typeAliases><!-- 最常用--><typeAliases> <package name="domain.blog"/></typeAliases>
mappers
引入對應檔
<!-- Using classpath relative resources --><mappers> <mapper resource="org/mybatis/builder/AuthorMapper.xml"/> <mapper resource="org/mybatis/builder/BlogMapper.xml"/> <mapper resource="org/mybatis/builder/PostMapper.xml"/></mappers><!-- Using url fully qualified paths --><mappers> <mapper url="file:///var/mappers/AuthorMapper.xml"/> <mapper url="file:///var/mappers/BlogMapper.xml"/> <mapper url="file:///var/mappers/PostMapper.xml"/></mappers><!-- Using mapper interface classes --><mappers> <mapper class="org.mybatis.builder.AuthorMapper"/> <mapper class="org.mybatis.builder.BlogMapper"/> <mapper class="org.mybatis.builder.PostMapper"/></mappers><!-- Register all interfaces in a package as mappers --><mappers> <package name="org.mybatis.builder"/></mappers>
settings
An example of the settings element fully configured is as follows:
<settings> <setting name="cacheEnabled" value="true"/> <setting name="lazyLoadingEnabled" value="true"/> <setting name="multipleResultSetsEnabled" value="true"/> <setting name="useColumnLabel" value="true"/> <setting name="useGeneratedKeys" value="false"/> <setting name="autoMappingBehavior" value="PARTIAL"/> <setting name="autoMappingUnknownColumnBehavior" value="WARNING"/> <setting name="defaultExecutorType" value="SIMPLE"/> <setting name="defaultStatementTimeout" value="25"/> <setting name="defaultFetchSize" value="100"/> <setting name="safeRowBoundsEnabled" value="false"/> <setting name="mapUnderscoreToCamelCase" value="false"/> <setting name="localCacheScope" value="SESSION"/> <setting name="jdbcTypeForNull" value="OTHER"/> <setting name="lazyLoadTriggerMethods" value="equals,clone,hashCode,toString"/></settings>
plugins
外掛程式 比如:
分頁外掛程式
<plugins> <plugin interceptor="com.github.pagehelper.PageHelper"> <property name="dialect" value="mysql"/> <property name="offsetAsPageNum" value="true"/> <property name="rowBoundsWithCount" value="true"/> <property name="pageSizeZero" value="true"/> </plugin></plugins>
感謝閱讀,希望能協助到大家,謝謝大家對本站的支援!