1- 修改my.cnf server-id=1 #服务器id (主从必须不一样) log-bin=master-bin #打开日志(主机需要打开) log-bin-index=master-bin.index 重启mysql mysql -uroot -p - show master status; 登陆Master主机，创建mysql 的slave用户 IDENTIFIED create user repl; GRANT REPLICATION SLAVE ON *.* TO 'repl'@'192.168.88.129' IDENTIFIED BY 'mysql'; docker 环境应该改为否则从库连接不上主库 GRANT REPLICATION SLAVE ON *.* TO 'repl'@'%' IDENTIFIED BY 'mysql'; flush privileges; 1- 修改my.cnf server_id=2 relay-log-index=slave-relay-bin.index relay-log=slave-relay-bin 重启mysql mysql -uroot -p - change master to master_host='192.168.88.129',master_port=3306,master_user='repl',master_password='mysql',master_log_file='master-bin.000001',master_log_pos=0; start slave; show slave status \G; stop slave; 主从库: GRANT select,insert,update,delete ON *.* TO 'work'@'%' IDENTIFIED BY '230230' WITH GRANT OPTION; flush privileges; GRANT select,insert,update,delete ON *.* TO 'work'@'%' IDENTIFIED BY '230230' WITH GRANT OPTION; flush privileges;
基于xml构建Spring项目
- jdbc.properties jdbc.driver=com.mysql.jdbc.Driver jdbc.master.url=jdbc:mysql://192.168.88.129:3309/o2o?useUnicode=true&characterEncoding=utf8 jdbc.username=work jdbc.password=230230 jdbc.slave.url=jdbc:mysql://192.168.88.129:3306/o2o?useUnicode=true&characterEncoding=utf8
- spring-dao.xml<context:property-placeholder location="classpath:jdbc.properties"/>
<!-- 2.数据库连接池 -->
<bean id="abstractDataSource" class="com.mchange.v2.c3p0.ComboPooledDataSource" abstract="true" destroy-method="close">
<!-- c3p0连接池的私有属性 -->
<property name="maxPoolSize" value="30" />
<property name="minPoolSize" value="10" />
<!-- 关闭连接后不自动commit -->
<property name="autoCommitOnClose" value="false" />
<!-- 获取连接超时时间 -->
<property name="checkoutTimeout" value="10000" />
<!-- 当获取连接失败重试次数 -->
<property name="acquireRetryAttempts" value="2" />
</bean>
<!-- 配置主从 start -->
<bean id="master" parent="abstractDataSource">
<!-- 配置连接池属性 -->
<property name="driverClass" value="${jdbc.driver}" />
<property name="jdbcUrl" value="${jdbc.master.url}" />
<property name="user" value="${jdbc.username}" />
<property name="password" value="${jdbc.password}" />
</bean>
<bean id="slave" parent="abstractDataSource">
<!-- 配置连接池属性 -->
<property name="driverClass" value="${jdbc.driver}" />
<property name="jdbcUrl" value="${jdbc.slave.url}" />
<property name="user" value="${jdbc.username}" />
<property name="password" value="${jdbc.password}" />
</bean>
<!-- 配置动态数据源-->
<bean id="dynamicDataSource" class="com.fayayo.o2o.dao.split.DynamicDataSource">
<property name="targetDataSources">
<map>
<entry value-ref="master" key="master"></entry>
<entry value-ref="slave" key="slave"></entry>
</map>
</property>
</bean>
<!-- 懒加载数据源-->
<bean id="dataSource" class="org.springframework.jdbc.datasource.LazyConnectionDataSourceProxy">
<property name="targetDataSource">
<ref bean="dynamicDataSource"/>
</property>
</bean>
<!-- 配置主从 end -->
<!-- 3.配置SqlSessionFactory对象 -->
<bean id="sqlSessionFactory" class="org.mybatis.spring.SqlSessionFactoryBean">
<!-- 注入数据库连接池 -->
<property name="dataSource" ref="dataSource" />
<!-- 配置MyBaties全局配置文件:mybatis-config.xml -->
<property name="configLocation" value="classpath:mybatis-config.xml" />
<!-- 扫描entity包 使用别名 -->
<property name="typeAliasesPackage" value="com.fayayo.o2o.entity" />
<!-- 扫描sql配置文件:mapper需要的xml文件 -->
<property name="mapperLocations" value="classpath:mapper/*.xml" />
</bean>
<!-- 4.配置扫描Dao接口包，动态实现Dao接口，注入到spring容器中 -->
<bean class="org.mybatis.spring.mapper.MapperScannerConfigurer">
<!-- 注入sqlSessionFactory -->
<property name="sqlSessionFactoryBeanName" value="sqlSessionFactory" />
<!-- 给出需要扫描Dao接口包 -->
<property name="basePackage" value="com.fayayo.o2o.dao" />
</bean>- spring-service.xml<!-- 扫描service包下所有使用注解的类型 -->
<context:component-scan base-package="com.fayayo.o2o.service" />
<!-- 配置事务管理器 -->
<bean id="transactionManager"
class="org.springframework.jdbc.datasource.DataSourceTransactionManager">
<!-- 注入数据库连接池 -->
<property name="dataSource" ref="dataSource" />
</bean>
<!-- 配置基于注解的声明式事务 -->
<tx:annotation-driven transaction-manager="transactionManager" />- spring-web.xml<mvc:annotation-driven />
<!-- 2.静态资源默认servlet配置 (1)加入对静态资源的处理：js,gif,png (2)允许使用"/"做整体映射 -->
<mvc:resources mapping="/resources/**" location="/resources/" />
<mvc:default-servlet-handler />
<!-- 3.定义视图解析器 -->
<bean id="viewResolver"
class="org.springframework.web.servlet.view.InternalResourceViewResolver">
<property name="prefix" value="/WEB-INF/html/"></property>
<property name="suffix" value=".html"></property>
</bean>
<!-- 在spring-mvc.xml文件中加入这段配置后，spring返回给页面的都是utf-8编码了 -->
<bean
class="org.springframework.web.servlet.mvc.annotation.AnnotationMethodHandlerAdapter">
<property name="messageConverters">
<list>
<bean
class="org.springframework.http.converter.StringHttpMessageConverter">
<property name="supportedMediaTypes">
<list>
<value>text/html;charset=UTF-8</value>
</list>
</property>
</bean>
</list>
</property>
</bean>
<!-- 4.扫描web相关的bean -->
<context:component-scan base-package="com.fayayo.o2o.web" />
<!-- 5.权限拦截器 -->
<mvc:interceptors>
<mvc:interceptor>
<!--<mvc:mapping path="/**" />-->
<mvc:mapping path="/area/**" />
<bean id="httpInterceptor" class="com.fayayo.o2o.interceptor.HttpInterceptor"/>
</mvc:interceptor>
</mvc:interceptors>
- mybatis-config.xml
<!-- 配置全局属性 -->
<settings>
<!-- 使用jdbc的getGeneratedKeys获取数据库自增主键值 -->
<setting name="useGeneratedKeys" value="true" />
<!-- 使用列别名替换列名 默认:true -->
<setting name="useColumnLabel" value="true" />
<!-- 开启驼峰命名转换:Table{create_time} -> Entity{createTime} -->
<setting name="mapUnderscoreToCamelCase" value="true" />
<!-- 打印查询语句 -->
<setting name="logImpl" value="STDOUT_LOGGING" />
</settings>
<plugins>
<plugin interceptor="com.fayayo.o2o.dao.split.DynamicDataSourceInterceptor"></plugin>
</plugins> 实现动态数据源
public class DynamicDataSource extends AbstractRoutingDataSource {
@Override
protected Object determineCurrentLookupKey() {
return DynamicDataSourceHolder.getDbType();
}
}public class DynamicDataSourceHolder {
private static ThreadLocal<String>contextHolder=new ThreadLocal<>();
public static final String DB_MASTER="master";
public static final String DB_SLAVE="slave";
public static String getDbType(){
String dbType=contextHolder.get();
if(dbType==null){
dbType=DB_MASTER;
}
return dbType;
}
public static void setDbType(String dbType){
System.out.println("================>所使用的数据源是:"+dbType);
contextHolder.set(dbType);
}
public static void clearDbType(){
System.out.println("================>回收Holder");
contextHolder.remove();
}
}
/**
* @author xxx on 2018/10/20.
* @version v1.0
* @desc 基于Mybatis的拦截器 拦截sql信息
*/
@Intercepts({@Signature(type = Executor.class, method = "update", args = {MappedStatement.class, Object.class}),
@Signature(type = Executor.class, method = "query", args = {MappedStatement.class, Object.class, RowBounds.class, ResultHandler.class})})
public class DynamicDataSourceInterceptor implements Interceptor {
private static final String REGEX = ".*insert\\u0020.*|.*delete\\u0020.*|.*update\\u0020.*";
@Override
public Object intercept(Invocation invocation) throws Throwable {
System.out.println("判断主从数据库的拦截器......");
//判断当前是否是事务
boolean synchronizationActive = TransactionSynchronizationManager.isActualTransactionActive();
Object[] objects = invocation.getArgs();//获取sql的变量参数
MappedStatement ms = (MappedStatement) objects[0];
String lookupKey = DynamicDataSourceHolder.DB_MASTER;//决定dataSource
if (synchronizationActive != true) {
//读方法
if (ms.getSqlCommandType().equals(SqlCommandType.SELECT)) {
//selectKey为自增id查询主键(SELECT LAST_INSERT_ID())方法，使用主库
if (ms.getId().contains(SelectKeyGenerator.SELECT_KEY_SUFFIX)) {
lookupKey = DynamicDataSourceHolder.DB_MASTER;
} else {
BoundSql boundSql = ms.getSqlSource().getBoundSql(objects[1]);
String sql = boundSql.getSql().toLowerCase(Locale.CHINA).replace("[\\t\\n\\r]", " ");
if (sql.matches(REGEX)) {
lookupKey = DynamicDataSourceHolder.DB_MASTER;//增删改使用主库
} else {
lookupKey = DynamicDataSourceHolder.DB_SLAVE;//读使用从库
}
}
}
} else {//事务管理使用主库
lookupKey = DynamicDataSourceHolder.DB_MASTER;
}
System.out.println("设置方法详细信息:" + ms.getId() + "," + lookupKey + "," + ms.getSqlCommandType().name());
DynamicDataSourceHolder.setDbType(lookupKey);//设置最终的数据源
return invocation.proceed();
}
@Override
public Object plugin(Object o) {
if (o instanceof Executor) {//增删改查的操作 拦截
return Plugin.wrap(o, this);
} else {
return o;
}
}
@Override
public void setProperties(Properties properties) {
}
}
- 项目拦截器
@Slf4j
public class HttpInterceptor extends HandlerInterceptorAdapter {
@Override
public boolean preHandle(HttpServletRequest request, HttpServletResponse response, Object handler) throws Exception {
return true;
}
@Override
public void postHandle(HttpServletRequest request, HttpServletResponse response, Object handler, ModelAndView modelAndView) throws Exception {
// 正常返回时, 显式回收threadLocal里的信息
removeThreadLocalInfo();
}
@Override
public void afterCompletion(
HttpServletRequest request, HttpServletResponse response, Object handler, Exception ex)
throws Exception {
// 出异常时, 显式回收threadLocal里的信息
removeThreadLocalInfo();
}
private void removeThreadLocalInfo() {
DynamicDataSourceHolder.clearDbType();
}
}实现上面的类之后，搭配spring-*.xml中的数据源配置
就可以实现主从分离了。要先创建好自己的mapper，进行数据库的增删改查。
需要源码可以留言。
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