1.Config

Config有4个实现类

1. InternamHSFConfig
2. EdasConfig
3. ApplicationHSFConfig
4. SystemConfig

1.1 Config接口

AbstractConfig是Config的默认抽象实现

1.2 其中继承自AbstractPropertiesConfig的都是读取properties文件,

如InternalHSFConfig,重写getResourceName方法,即读取internal_hsf_config.properties文件

public class InternalHSFConfig extends AbstractFrameworkPropertiesConfig {
    public InternalHSFConfig() {
    }

    protected String getResourceName() {
        return "internal_hsf_config.properties";
    }
}

1.3 SystemConfig

读取系统属性

public class SystemConfig extends AbstractConfig {
    public SystemConfig() {
    }

    protected String findProperty(String key) {
        return System.getProperty(key);
    }

    protected Set<String> findKeys() {
        return new HashSet(System.getProperties().stringPropertyNames());
    }
}

2.ConfigService

ConfigService接口非常简单，只返回一个Config实例

public interface ConfigService {
    Config getConfig();
}

其内部实现了Config初始化逻辑,源码如下:

public class ConfigServiceImpl implements ConfigService, ApplicationModelAware, FrameworkModelAware {
    private Config config;

    public ConfigServiceImpl() {
    }

    public Config getConfig() {
        return this.config;
    }

    public void setApplicationModel(ApplicationModel applicationModel) {
        this.loadConfig(applicationModel.getServiceContainer());
    }

    public void setFrameworkModel(FrameworkModel frameworkModel) {
        this.loadConfig(HSFServiceContainer.SHARED_CONTAINER);
    }

    private void loadConfig(AppServiceContainer appServiceContainer) {
        List<Config> configList = appServiceContainer.getInstances(Config.class);
        Collections.reverse(configList);
            for(int i = 0; i < size - 1; ++i) {
                AbstractConfig config = (AbstractConfig)configList.get(i);
                config.setParent((AbstractConfig)configList.get(i + 1));
                config.init();
            }
            this.config = (Config)configList.get(0);
    }
}

分析一下上面代码

1.List<Config> configList = appServiceContainer.getInstances(Config.class);

首先看一下配置文件com.taobao.hsf.configuration.Config,有3个Config,EdasConfig则在另一个项目里面

com.taobao.hsf.configuration.impl.SystemConfig
com.taobao.hsf.configuration.impl.InternalHSFConfig
com.taobao.hsf.configuration.impl.ApplicationHSFConfig

获取Config列表,这有点spring boot的感觉,与其使用方法基本一致

2.AbstractConfig有一个parent属性,指向下一个Config,每次获取属性时，则先向父Config获取配置，最后一个Config没有调用init方法,即SystemConfig

    public <T> T getProperty(Class<T> cls, String key) {
        if (cls == null) {
            throw new IllegalArgumentException("property class is null");
        } else {
            T result = null;
            if (this.parent != null) {
                result = this.parent.getProperty(cls, key);
            }

            if (result == null) {
                String value = this.findProperty(key);
                if (value != null) {
                    result = this.convertValue(cls, value);
                }
            }
            return result;
        }
    }

所以ConfigService只需要返回一个Config,实际其内部是一个链表获取操作,如下堆栈

3.Env

Env是对Config中key,value的Bean化包装,更加通俗易懂些

public class EnvImpl implements Env {
    private Config config = ((ConfigService)HSFServiceContainer.getInstance(ConfigService.class)).getConfig();
 
    public EnvImpl() {
        this.bindHost = this.config.getString("HsfBindHost", this.config.getString("hsf.server.ip", this.getHostIp()));
        this.bindPort = this.config.getInt("hsf.server.port");
        this.bindHttpPort = this.config.getInt("hsf.http.port");
        //...
    }