miaoyachun

/**
 * 重载合并属性实现
 * 先加载file properties， 然后并入ZK配置中心读取的properties
 *
 * @return 合并后的属性集合
 * @throws IOException 异常
 */
@Override
protected Properties mergeProperties() throws IOException {
    Properties result = new Properties();
    // 加载父类的配置
    Properties mergeProperties = super.mergeProperties();
    result.putAll(mergeProperties);
    // 加载从zk中读取到的配置
    Map<String, String> configs = loadZkConfigs();
    result.putAll(configs);
    return result;
}

/**
 * 重载处理属性实现
 * 根据选项, 决定是否将合并后的props写入系统属性, Spring boot需要
 *
 * @param beanFactoryToProcess
 * @param props                合并后的属性
 * @throws BeansException
 */
@Override
protected void processProperties(ConfigurableListableBeanFactory beanFactoryToProcess, Properties props) throws BeansException {
    // 原有逻辑
     super.processProperties(beanFactoryToProcess, props);
    // 写入到系统属性
    if (writePropsToSystem) {
       // write all properties to system for spring boot
        Enumeration<?> propertyNames = props.propertyNames();
        while (propertyNames.hasMoreElements()) {
             String propertyName = (String) propertyNames.nextElement();
             String propertyValue = props.getProperty(propertyName);
             System.setProperty(propertyName, propertyValue);
        }
    }
}

@Override
public Object postProcessBeforeInitialization(Object bean, String beanName)
      throws BeansException {
   ConfigurationProperties annotation = AnnotationUtils
         .findAnnotation(bean.getClass(), ConfigurationProperties.class);
   if (annotation != null) {
      postProcessBeforeInitialization(bean, beanName, annotation);
 }
   annotation = this.beans.findFactoryAnnotation(beanName,
 ConfigurationProperties.class);
   if (annotation != null) {
      postProcessBeforeInitialization(bean, beanName, annotation);
 }
   return bean;
}

解决思路有两个:

• 思路1: 想办法对静态变量注入, 也就是绕过Spring只能运行非静态变量才能注入依赖的壁垒
• 思路2: 想办法@AfterClass改造为非静态

  • 实现Junit RunListener, 覆盖testRunFinished方法, 这里去实现类似@AfterClass的功能, 这个方法是非静态的
  • 不要用Junit, 改用TestNG, TestNG里的AfterClass是非静态的
  • 用Spring的TestExecutionListeners, 实现个Listener, 里面也有个类似非静态的AfterClass的实现, 覆盖实现就行

思路2的几个方法都可以实现, 但是单元测试Runner需要用

@RunWith(Theories.class)

而且改用TestNG工程浩大, 只能放弃掉这个思路

继续走思路1, 只能去绕过Spring的依赖注入的static壁垒了, 具体代码如下:

 @Autowired
 private Destination dfsOperationQueue;
 private static Destination dfsOperationQueueStatic; // static version
 @Autowired
 private MessageQueueAPI messageQueueAPI;
 private static MessageQueueAPI messageQueueAPIStatic; // static version


 @PostConstruct
 public void init() {
        dfsOperationQueueStatic = this.dfsOperationQueue;
        messageQueueAPIStatic = this.messageQueueAPI;
 }

 @AfterClass
 public static void afterClass() {
        MessageVO messageVO = messageQueueAPIStatic.removeDestination(dfsOperationQueueStatic);
        System.out.println(messageVO);
 }

其实就是用了@PostConstruct 来个偷梁换柱而已, 多声明个静态成员指向非静态对象, 两者其实是一个对象

知道activemq现在已经支持了rest api, 但是官方对这部分的介绍一笔带过 (http://activemq.apache.org/rest.html),

通过google居然也没搜到一些有用的, 比如像删除一个destination, 都是问的多,然后没下文. 于是花了一些心思研究了一下:

首先通过rest api获取当前版本所有已支持的协议

    http://172.30.43.206:8161/api/jolokia/list

然后根据json输出关于removeTopic, removeQueue的mbean实现通过rest api删除destination的方法, 注意到用GET请求而不是POST,不然会报错 (官网的例子里用的wget给的灵感, 开始用了POST老报错)

其他的请求,应该都是类似jolokia的exec get request的格式:

<base url>/exec/<mbean name>/<operation name>/<arg1>/<arg2>/.

server.compression.enabled=true 
server.compression.mime-types=application/json,application/xml,text/html,text/xml,text/plain
server.compression.min-response-size=4096

latency = client send request time + network trans time (->)+ server receive request time+ reponse time + server send reponse time+ network trans time (<-)+ client receive reponse time

latency = first byte out, last byte in time

In many cases, binaries can no longer dump core after calling setuid(). 
Under Linux it is possible to re-enable this with a system call.

e.g.

Manual of prctl

Ref: http://bugs.mysql.com/bug.php?id=21723
Some files about linux core dump: