(一)

http://www.cnblogs.com/jietang/p/5615681.html

提供了一个Netty+Protobuf的RPC解决方案,并提供了demo:

https://github.com/tang-jie/NettyRPC


clone该demo,maven编译,有一个ojdbc6无法下载,查找资料



由于需要oracle官方授权,所以maven上无法下载ojdbc,需要自己下载,然后通过命令加载到本地maven库中,详细步骤如下


1、到官方下载,地址:http://www.oracle.com/technetwork/indexes/downloads/index.html,找到“drivers”-“jdbc Drivers”,打开,点击同意协议,就可以选择版本下载了

2、假设下载的是11.2.0.1.0,放在本地

3、打开命令行窗口,执行以下命令加载到本地

[plain]  view plain  copy
  1. mvn install:install-file -DgroupId=com.oracle -DartifactId=ojdbc6 -Dversion=11.2.0.1.0 -Dpackaging=jar -Dfile=ojdbc6.jar  

重新编译  ok  ,target目录下生成

NettyRPC-1.0-SNAPSHOT.jar


运行该服务


java -jar <jar-file-name>.jar


            _   _                         

           | | | |                        

 _ __   ___| |_| |_ _   _ _ __ _ __   ___ 

| '_ \ / _ \ __| __| | | | '__| '_ \ / __|

| | | |  __/ |_| |_| |_| | |  | |_) | (__ 

|_| |_|\___|\__|\__|\__, |_|  | .__/ \___|

                     __/ |    | |         

                    |___/     |_|         


[NettyRPC 2.0,Build 2016/10/7,Author:tangjie http://www.cnblogs.com/jietang/]

[author tangjie] Netty RPC Server start success!

ip:127.0.0.1

port:18887

protocol:You can open your web browser see NettyRPC server api interface: http://127.0.0.1:18886/NettyRPC.html

RpcSerializeProtocol[serializeProtocol=protostuff,name=PROTOSTUFFSERIALIZE,ordinal=3]



然后运行客户端:

com.newlandframework.test.RpcParallelTest
 
 
客户端显示:
......
calc multi result:[992016]
乘法计算RPC调用总共耗时: [974] 毫秒
[author tangjie] Netty RPC Server 消息协议序列化第[0]轮并发验证结束!
 
 
服务端显示:
 
 

.......

RPC Server Send message-id respone:6abe54e6-d9ef-44d7-ab4e-28a86f817dd3

RPC Server Send message-id respone:6d3a3e1c-198a-4c95-9df4-6af32f571dec

RPC Server Send message-id respone:aa46cf22-7a0c-4c47-afc1-0a68e682bd75

RPC Server Send message-id respone:7f04cc95-4c3a-483f-9322-005ae9c3082e

RPC Server Send message-id respone:cdca0293-404b-4dbf-a11d-2be9a15ca7ee

RPC Server Send message-id respone:bc9144b8-3d50-438d-92df-8ef8ec6d4255

done







(二)10.16 调试其jdbc部分(NettyRpcJdbcServerTest


首先需要数据库支持,更换掉oracle的ojdbc6,换为mysql引擎:

        <dependency>
            <groupId>mysql</groupId>
            <artifactId>mysql-connector-java</artifactId>
            <version>5.1.6</version>
        </dependency>


我们首先要编译运行/test/jdbc/NettyRpcJdbcServerTest.java:

public class NettyRpcJdbcServerTest {
    // FIXME: 2017/9/25 确保先启动NettyRPC服务端应用:NettyRpcJdbcServerTest,再运行NettyRpcJdbcClientTest、NettyRpcJdbcClientErrorTest!
    public static void main(String[] args) {
        new ClassPathXmlApplicationContext("classpath:rpc-invoke-config-jdbc-server.xml");
    }
}


找到rpc-invoke-config-jdbc-server.xml: 更换其中的datasource bean:

原:

    <bean id="dataSource" class="com.alibaba.druid.pool.DruidDataSource" init-method="init" destroy-method="close">
        <property name="driverClassName" value="oracle.jdbc.driver.OracleDriver"/>
        <property name="url" value="jdbc:oracle:thin:@10.1.0.211:1521:kf"/>
        <property name="username" value="ccs_nd"/>
        <property name="password" value="ccs_nd"/>
    </bean>

改为mysql的:

    <bean id="dataSource" class="com.alibaba.druid.pool.DruidDataSource" init-method="init" destroy-method="close">
        <property name="driverClassName" value="com.mysql.jdbc.Driver"/>
        <property name="url" value="jdbc:mysql://xxx.1xx.xx2.xx4:3306/test?useUnicode=yes&characterEncoding=UTF-8"/>
        <property name="username" value="xxx"/>
        <property name="password" value="xxx"/>
    </bean>

在mysql中建立Person表

CREATE TABLE `person` (
  `id` int(11) NOT NULL AUTO_INCREMENT,
  `name` varchar(32) CHARACTER SET utf8mb4 COLLATE utf8mb4_unicode_ci NOT NULL DEFAULT '',
  `age` int(11) NOT NULL,
  `birthday` datetime DEFAULT NULL,
  PRIMARY KEY (`id`)
) ENGINE=MyISAM AUTO_INCREMENT=2 DEFAULT CHARSET=utf8 COLLATE=utf8_bin COMMENT='test';


编译运行

Server,运行NettyRpcJdbcClientTest
客户端显示:

call pojo rpc result:0
---------------------------------------------
Person <<id:1 name:小好 age:2 birthday:Tue Aug 11 16:47:00 CST 2015>>
Person <<id:2 name:小好 age:2 birthday:Tue Aug 11 16:47:00 CST 2015>>


Process finished with exit code 0


done,


期间,要更换 oracle的to_date 为mysql的str_to_date函数










(三)10.20

加入log4j


参考:http://harborchung.iteye.com/blog/2271509

在主函数中添加

PropertyConfigurator.configure("classes/log4j.properties");










(四)11.13  加入 自动装配jdbctemplate,aop统一处理异常处理,事务支持


首先来看自动装配jdbctemplate,此前是这样的:

JdbcTemplate template = new JdbcTemplate(this.dataSource);

    <bean id="MyPojoJdbc" class="com.newlandframework.rpc.services.impl.MyPojoImpl">
        <property name="dataSource" ref="dataSource"></property>  
    </bean>


public class MyPojoImpl implements MyPojo {
    private DataSource dataSource;

    public void setDataSource(DataSource dataSource) {
        this.dataSource = dataSource;
    }

利用setter注入MyPojoImpl的依赖项dataSource,然后直接实例化JdbcTemplae,这样就使jdbctemplate在spring托管之外


现改为:

public class MyPojoImpl implements MyPojo {
//    private DataSource dataSource;

    @Autowired
    private JdbcTemplate jdbcTemplate;

    private static Logger LOG = Logger.getLogger(MyPojoImpl.class);

//    public void setDataSource(DataSource dataSource) {
//        this.dataSource = dataSource;
//    }

    <bean id="MyPojoJdbc" class="com.newlandframework.rpc.services.impl.MyPojoImpl">
     <!--   <property name="dataSource" ref="dataSource"></property>  -->
    </bean>


运行,报错:jdbcTemplate为null,装配失败

参考:http://www.iteye.com/problems/92069


<context:annotation-config /> 
这句话才是激活Bean的属性上的自动注入相关的注释处理:Autowired之类 

<context:component-scan base-package =“sunships.dhcc”/> 
这个只是 搜索类,并按照类声明的注解作为合适的bean加入ApplicationContext 



在spring环境中加入:

<context:annotation-config />

运行ok,这个注解是告诉spring加载预定义的一些bean,Autowired在其中




然后处理aop统一异常处理:


添加:

@Aspect
public class AuthInterceptor {

    private static Logger LOG = Logger.getLogger(AuthInterceptor.class);

    @Pointcut("execution(* com.newlandframework.rpc.services.impl.*.*(..))")
    private void aroundMethod(){}//定义一个切入点

    @Around("aroundMethod()")
    public Object doBasicProfiling(ProceedingJoinPoint pjp) throws Throwable {

        Object object = null;

        try {
            System.out.println("aop start");
            object = pjp.proceed();//执行该方法
        } catch (Exception e) {
            System.out.println("aop exception");
            e.printStackTrace();
            LOG.error("global error:", e);
        }
        System.out.println("aop end");
        //    System.out.println("退出方法");
        return object;
    }

}

注入:

<aop:aspectj-autoproxy />
<bean id="myAOP" class="com.newlandframework.rpc.services.AuthInterceptor"></bean>


idea中aop标签报错,参考:http://blog.csdn.net/qq_37062668/article/details/74298491

添加

xmlns:aop="http://www.springframework.org/schema/aop"
mvn编译通过,运行,报错:

通配符的匹配很全面, 但无法找到元素 'aop:aspectj-autoproxy' 的声明。

xsi:schemaLocation中添加:


http://www.springframework.org/schema/aop http://www.springframework.org/schema/aop/spring-aop-4.3.xsd

编译运行:

aop start

jdbc Tao query!

[INFO] {RpcThreadPool-thread-1} com.newlandframework.rpc.services.impl.MyPojoImpl.queryList(66) | MyPojo.queryList done.

aop end

RPC Server Send message-id respone:4964cc58-3fd8-4385-83b8-3ee552165259


通过。


期间在pointcut上的报错

 

错误: warning no match for this type name: com.zrm.service [Xlint:invalidAbsoluteTypeName]

处理参考了http://blog.csdn.net/yangxiaovip/article/details/31797475

@Pointcut("execution(* com.newlandframework.rpc.services.impl.*(..))")
改为:

@Pointcut("execution(* com.newlandframework.rpc.services.impl.*.*(..))")




最后,调试异常事务回滚

@Aspect
public class AuthInterceptor {

    private static Logger LOG = Logger.getLogger(AuthInterceptor.class);

    @Pointcut("execution(* com.newlandframework.rpc.services.impl.*.*(..))")
    private void aroundMethod(){}//定义一个切入点

    @Around("aroundMethod()")
    public Object doBasicProfiling(ProceedingJoinPoint pjp) throws Throwable {

        Object object = null;

        try {
            System.out.println("aop start");
            object = pjp.proceed();//执行该方法
        } catch (Exception e) {
            System.out.println("aop exception");
            e.printStackTrace();
            LOG.error("global error:", e);
            TransactionAspectSupport.currentTransactionStatus().setRollbackOnly();
        }
        System.out.println("aop end");
        //    System.out.println("退出方法");
        return object;
    }

}

主要是加入

TransactionAspectSupport.currentTransactionStatus().setRollbackOnly();

事务处理器注入

    <bean id="sqlTxManager"
          class="org.springframework.jdbc.datasource.DataSourceTransactionManager">
        <property name="dataSource" ref="dataSource"/>
    </bean>

    <tx:annotation-driven transaction-manager="sqlTxManager"/>

特意建立函数:

    @Transactional
    @Override
    public List<Tao> queryListError() {

        System.out.println("jdbc Tao query!");

        String insertSql = "insert into tao (col2) values ('call exception')";
        jdbcTemplate.execute(insertSql);

        String sql = "select * from tao2";
     //   JdbcTemplate template = new JdbcTemplate(this.dataSource);
        
        List<Map<String, Object>> rows = jdbcTemplate.queryForList(sql);

        return null;
    }

先插入,后执行错误sql语句,加上Transactional注解

aop start
jdbc Tao query!
aop exception
org.springframework.jdbc.BadSqlGrammarException: StatementCallback; bad SQL grammar [select * from tao2]; nested exception is com.mysql.jdbc.exceptions.jdbc4.MySQLSyntaxErrorException: Table 'amac_data_test.tao2' doesn't exist
	at org.springframework.jdbc.support.SQLErrorCodeSQLExceptionTranslator.doTranslate(SQLErrorCodeSQLExceptionTranslator.java:231)
	at org.springframework.jdbc.support.AbstractFallbackSQLExceptionTranslator.translate(AbstractFallbackSQLExceptionTranslator.java:73)
	at org.springframework.jdbc.core.JdbcTemplate.execute(JdbcTemplate.java:413)
	at org.springframework.jdbc.core.JdbcTemplate.query(JdbcTemplate.java:468)
	at org.springframework.jdbc.core.JdbcTemplate.query(JdbcTemplate.java:478)
	at org.springframework.jdbc.core.JdbcTemplate.queryForList(JdbcTemplate.java:518)
	at com.newlandframework.rpc.services.impl.MyPojoImpl.queryListError(MyPojoImpl.java:83)

且回滚成功,并未插入数据

此过程中

@Transactional
注解和,

TransactionAspectSupport.currentTransactionStatus().setRollbackOnly();

缺一不可,done










(五)12.21   netty客户端与web项目的结合


1.最初,每个请求都遵循

    @RequestMapping(value = "testNetty", method = RequestMethod.POST)
    @ResponseBody
    @ApiImplicitParams({})
    @ApiOperation(value="testNetty")
    public Object testNetty() {

        ClassPathXmlApplicationContext context = new ClassPathXmlApplicationContext("classpath:netty.xml");

        MyPojo manage = (MyPojo) context.getBean("MyPojoJdbc");
        List<Tao> list = null;

        try {

            list = manage.queryList();
            for (int i = 0; i < list.size(); i++) {
                System.out.println(list.get(i));
            }
        } catch (Exception e) {
            e.printStackTrace();
        } finally {
            context.destroy();
        }

        return list;
    }

每次请求完都释放netty的context,

context.destroy()导致

ClientStopEventListener
被激发,如下:
 
 
public class ClientStopEventListener {
    public int lastMessage = 0;

    @Subscribe
    public void listen(ClientStopEvent event) {
        lastMessage = event.getMessage();
        // sunyuming
        MessageSendExecutor.getInstance().stop();
    }

    public int getLastMessage() {
        return lastMessage;
    }
}

    public void stop() {
        loader.unLoad();
    }
    public void unLoad() {
        messageSendHandler.close();
        threadPoolExecutor.shutdown();
        eventLoopGroup.shutdownGracefully();
    }

其中,
private static ListeningExecutorService threadPoolExecutor = MoreExecutors.listeningDecorator((ThreadPoolExecutor) RpcThreadPool.getExecutor(threadNums, queueNums));

静态线程池反复操作释放后挂了
 
 
故有了2
 
 
 
 
2.
 
 
 
 
public class ClientStopEventListener {
    public int lastMessage = 0;

    @Subscribe
    public void listen(ClientStopEvent event) {
        lastMessage = event.getMessage();
        // sunyuming
     //   MessageSendExecutor.getInstance().stop();
    }

    public int getLastMessage() {
        return lastMessage;
    }
}
 
 
@WebListener
public class MyServletContextListener implements ServletContextListener {
    @Override
    public void contextDestroyed(ServletContextEvent arg0) {

        MessageSendExecutor.getInstance().stop();
    }


}

监听spring web context的销毁,在其中激发各种线程资源的回收,取消对netty context销毁的监控中stop函数,这样,线程资源只会回收一次,不会报错,也跑起来了
但每次请求都创建netty context太耗费资源,显然不行,于是有了3
 
 
 
 
 
 
 
 
3.
 
 
public static final ClassPathXmlApplicationContext NETTY_CONTEXT = new ClassPathXmlApplicationContext("classpath:netty.xml");
 
 
这样就只创建一次,销毁时 
 
@WebListener
public class MyServletContextListener implements ServletContextListener {
    @Override
    public void contextDestroyed(ServletContextEvent arg0) {


        System.out.println("netty销毁");
        // sunyuming
        OrgNewController.NETTY_CONTEXT.destroy();
        MessageSendExecutor.getInstance().stop();
    }

}


ok,正常允许,但其实已经埋下了隐患:

正常的销毁顺序应该为

spring context destroy 中触发 netty context destroy   再触发  MassageSendExecutor.getInstance().stop()

此时的代码为:

spring context destory 中直接同时触发MassageSendExecutor.getInstance().stop(),再触发 netty context destroy ,其中MassageSendExecutor.getInstance().stop()由原本在netty context destroy中,移动到 spring web context destroy中直接处理了

然后就发生隐患了





4.有2个web项目要用到netty client,在操作第二个时,代码复制过去后,出现tomcat shutdown之后没有关闭进程,根据以往的经验:http://blog.csdn.net/silyvin/article/details/72678375

直接吧问题定位到线程池未shutdown导致内存泄露


回想此时的代码:

web2这个项目没有监听spring context destroy

复制过去的netty代码中缺少MassageSendExecutor.getInstance().stop(),(因为被移动到web1的spring context destroy中去了),所以线程没有释放,导致泄露

解决方案:




5.于是回归规范,将自行在netty client 中监听netty context销毁的代码中恢复MassageSendExecutor.getInstance().stop()


public class ClientStopEventListener {
    public int lastMessage = 0;

    @Subscribe
    public void listen(ClientStopEvent event) {
        lastMessage = event.getMessage();
        // sunyuming
        MessageSendExecutor.getInstance().stop();
    }

    public int getLastMessage() {
        return lastMessage;
    }
}


在web1中,去除对MassageSendExecutor.getInstance().stop()的显式直接操作:

    @Override
    public void contextDestroyed(ServletContextEvent arg0) {

        System.out.println("netty销毁");
        // sunyuming
        OrgNewController.NETTY_CONTEXT.destroy();
    //    MessageSendExecutor.getInstance().stop();
    }


这样就经由正确的路线去释放资源   spring web context destroy --》 netty context destroy --》MassageSendExecutor.getInstance().stop()
在web2中也添加对spring web context destroy 的监听
解决


转载于:https://www.cnblogs.com/silyvin/p/9106758.html

Logo

开放原子开发者工作坊旨在鼓励更多人参与开源活动,与志同道合的开发者们相互交流开发经验、分享开发心得、获取前沿技术趋势。工作坊有多种形式的开发者活动,如meetup、训练营等,主打技术交流,干货满满,真诚地邀请各位开发者共同参与!

更多推荐