springCloud 中的 archaius 的一些用法

先上一个例子代码

public static void main( String[] args ) throws IOException {

	DynamicStringProperty stringProperty = DynamicPropertyFactory.getInstance().getStringProperty( "hello", "" );

	System.out.println( stringProperty.get() );

	ConfigurationManager.getConfigInstance().setProperty( "name", "Jay" );
		
	ConfigurationManager.getConfigInstance().setProperty( "name", "Join" );

	System.out.println( ConfigurationManager.getConfigInstance().getString( "name" ) );

	ConfigurationManager.loadCascadedPropertiesFromResources( "application" );
		// eureka-client
	DynamicPropertyFactory propertyFactory = Archaius1Utils.initConfig( CommonConstants.CONFIG_FILE_NAME );
		
	System.out.println( propertyFactory.getStringProperty( "a", "" ).get() );

}

 src/main/resources 需要有 application.properties， config.properties,  eureka-client.properties 这几个properties 文件。如图：

 

 

ConfigurationManager.getConfigInstance();  默认是加载 src/main/resources 下的  config.properties 文件。

下面 看看源代码是怎么做的

 

public static AbstractConfiguration getConfigInstance() {


	if ( instance == null ) {

		synchronized ( ConfigurationManager.class ) {

			if ( instance == null ) {

				// archaius.dynamicProperty.disableDefaultConfig
				instance = getConfigInstance( Boolean.getBoolean( DynamicPropertyFactory.DISABLE_DEFAULT_CONFIG ) );

			}

		}

	}

	return instance;

}

 单例模式 获取 AbstractConfiguration

// false
private static AbstractConfiguration getConfigInstance( boolean defaultConfigDisabled ) {

	if ( instance == null && !defaultConfigDisabled ) {

		instance = createDefaultConfigInstance();

		registerConfigBean();

	}

	return instance;

}

 直接 看 createDefaultConfigInstance 方法

private static AbstractConfiguration createDefaultConfigInstance() {
        // 组合配置
	ConcurrentCompositeConfiguration config = new ConcurrentCompositeConfiguration();

	try {

		DynamicURLConfiguration defaultURLConfig = new DynamicURLConfiguration();

		// archaius.dynamicPropertyFactory.URL_CONFIG
		config.addConfiguration( defaultURLConfig, URL_CONFIG_NAME );

	} catch ( Throwable e ) {

		logger.warn( "Failed to create default dynamic configuration", e );

	}

	// archaius.dynamicProperty.disableSystemConfig
	if ( !Boolean.getBoolean( DISABLE_DEFAULT_SYS_CONFIG ) ) {

		SystemConfiguration sysConfig = new SystemConfiguration();

		config.addConfiguration( sysConfig, SYS_CONFIG_NAME );

	}

	// archaius.dynamicProperty.disableEnvironmentConfig
	if ( !Boolean.getBoolean( DISABLE_DEFAULT_ENV_CONFIG ) ) {

		EnvironmentConfiguration envConfig = new EnvironmentConfiguration();

		config.addConfiguration( envConfig, ENV_CONFIG_NAME );

	}

	ConcurrentCompositeConfiguration appOverrideConfig = new ConcurrentCompositeConfiguration();

	// APPLICATION_PROPERTIES
	config.addConfiguration( appOverrideConfig, APPLICATION_PROPERTIES );

	config.setContainerConfigurationIndex( config.getIndexOfConfiguration( appOverrideConfig ) );

	return config;

}

 ConcurrentCompositeConfiguration config = new ConcurrentCompositeConfiguration(); 

这个类是一个配置的集合，可以加载多个配置文件，每个配置文件都加在到自己单独的AbstractConfiguration 中。

 

private Map<String, AbstractConfiguration> namedConfigurations = new ConcurrentHashMap<String, AbstractConfiguration>();

private List<AbstractConfiguration> configList = new CopyOnWriteArrayList<AbstractConfiguration>();

 configList 就是配置的集合， 如果要查找 其中的一个属性配置，就要循环 configList 中的每一个 AbstractConfiguration  一直到找到为止。

 

ConcurrentCompositeConfiguration  这个类默认添加一个 ConcurrentMapConfiguration ，使用的观察者模式， 代码如下

 

public final void clear() {

	fireEvent( EVENT_CLEAR, null, null, true );

	configList.clear();

	namedConfigurations.clear();

	// recreate the in memory configuration
	containerConfiguration = new ConcurrentMapConfiguration();

	containerConfiguration.setThrowExceptionOnMissing( isThrowExceptionOnMissing() );

	containerConfiguration.setListDelimiter( getListDelimiter() );

	containerConfiguration.setDelimiterParsingDisabled( isDelimiterParsingDisabled() );
				
	containerConfiguration.addConfigurationListener( eventPropagater );

	configList.add( containerConfiguration );

	overrideProperties = new ConcurrentMapConfiguration();

	overrideProperties.setThrowExceptionOnMissing( isThrowExceptionOnMissing() );
				
	overrideProperties.setListDelimiter( getListDelimiter() );

	overrideProperties.setDelimiterParsingDisabled( isDelimiterParsingDisabled() );

	overrideProperties.addConfigurationListener( eventPropagater );

	fireEvent( EVENT_CLEAR, null, null, false );

	containerConfigurationChanged = false;

	invalidate();

}

 接下来看着2行代码

DynamicURLConfiguration defaultURLConfig = new DynamicURLConfiguration();

// archaius.dynamicPropertyFactory.URL_CONFIG

config.addConfiguration( defaultURLConfig, URL_CONFIG_NAME );

 

DynamicURLConfiguration 中的默认加载 config.properties 文件， 并且加入到  ConcurrentCompositeConfiguration 类中。

public DynamicURLConfiguration() {

	URLConfigurationSource source = new URLConfigurationSource();

	if ( source.getConfigUrls() != null && source.getConfigUrls().size() > 0 ) {

		startPolling( source, new FixedDelayPollingScheduler() );

	}

}

 

public URLConfigurationSource() {

	List<URL> urlList = new ArrayList<URL>();

	URL configFromClasspath = getConfigFileFromClasspath();

	if ( configFromClasspath != null ) {

		urlList.add( configFromClasspath );

	}

	String[] fileNames = getDefaultFileSources();

	if ( fileNames.length != 0 ) {

		urlList.addAll( Arrays.asList( createUrls( fileNames ) ) );

	}

	if ( urlList.size() == 0 ) {

		configUrls = new URL[ 0 ];

	} else {

		configUrls = urlList.toArray( new URL[ urlList.size() ] );


	}

}

 URL configFromClasspath = getConfigFileFromClasspath(); 看着一行

private URL getConfigFileFromClasspath() {

	URL url = null;

	// attempt to load from the context classpath
	ClassLoader loader = Thread.currentThread().getContextClassLoader();

	if ( loader != null ) {

		// config.properties
		url = loader.getResource( DEFAULT_CONFIG_FILE_FROM_CLASSPATH );

	}

	if ( url == null ) {

		// attempt to load from the system classpath
		url = ClassLoader.getSystemResource( DEFAULT_CONFIG_FILE_FROM_CLASSPATH );

	}

	if ( url == null ) {

		// attempt to load from the system classpath
		url = URLConfigurationSource.class.getResource( DEFAULT_CONFIG_FILE_FROM_CLASSPATH );

	}

	return url;

}

 public static final String DEFAULT_CONFIG_FILE_FROM_CLASSPATH = System.getProperty( "archaius.configurationSource.defaultFileName" ) == null ? DEFAULT_CONFIG_FILE_NAME : System.getProperty( "archaius.configurationSource.defaultFileName" );

 

也就是 config.properties 这个文件

也可以 -Darchaius.configurationSource.additionalUrls 加载指定的文件。 代码如下

private static final String[] getDefaultFileSources() {

	// archaius.configurationSource.additionalUrls
	String name = System.getProperty( CONFIG_URL );

	String[] fileNames;

	if ( name != null ) {

		fileNames = name.split( "," );

	} else {

		fileNames = new String[ 0 ];

	}

	return fileNames;

}

 DynamicURLConfiguration 还支持动态修改， 定时刷新

public DynamicURLConfiguration() {

	URLConfigurationSource source = new URLConfigurationSource();

	if ( source.getConfigUrls() != null && source.getConfigUrls().size() > 0 ) {

		startPolling( source, new FixedDelayPollingScheduler() );

	}

}

 

public FixedDelayPollingScheduler() {

	// archaius.fixedDelayPollingScheduler.initialDelayMills
	String initialDelayProperty = System.getProperty( INITIAL_DELAY_PROPERTY );

	if ( initialDelayProperty != null && initialDelayProperty.length() > 0 ) {

		initialDelayMillis = Integer.parseInt( initialDelayProperty );

	}
		
	// archaius.fixedDelayPollingScheduler.delayMills
	String delayProperty = System.getProperty( DELAY_PROPERTY );

	if ( delayProperty != null && delayProperty.length() > 0 ) {

		delayMillis = Integer.parseInt( delayProperty );

	}

}

 可以通过 -Darchaius.fixedDelayPollingScheduler.initialDelayMills 设置初始化延时，

-Darchaius.fixedDelayPollingScheduler.delayMills设置多久重新加载一次

 ConcurrentCompositeConfiguration 也可以禁止加载系统配置和环境配置

-Darchaius.dynamicProperty.disableSystemConfig 不加载系统配置

-Darchaius.dynamicProperty.disableEnvironmentConfig 不加载环境配置

-Darchaius.dynamicPropertyFactory.registerConfigWithJMX 设置启用JMX