Dubbo系列之Container初始化(二)

使用dubbo的人都会发现,它本身并没有内置什么启动容器,因为它启动的时候是通过特定的container实现,dubbo中有个模块就是管理各个容器的:

核心接口是 两个方法一个是启动,一个是停止

@SPI("spring")
public interface Container {

    /**
     * start.
     */
    void start();

    /**
     * stop.
     */
    void stop();

}

dubbo提供了三种容器管理的实现,分别是log4j,logback,spring

第一种是log4j的容器:Log4jContainer

package com.alibaba.dubbo.container.log4j;

import com.alibaba.dubbo.common.utils.ConfigUtils;
import com.alibaba.dubbo.container.Container;

import org.apache.log4j.Appender;
import org.apache.log4j.FileAppender;
import org.apache.log4j.LogManager;
import org.apache.log4j.PropertyConfigurator;

import java.util.Enumeration;
import java.util.Properties;

/**
 * Log4jContainer. (SPI, Singleton, ThreadSafe)
 */
public class Log4jContainer implements Container {

    public static final String LOG4J_FILE = "dubbo.log4j.file";

    public static final String LOG4J_LEVEL = "dubbo.log4j.level";

    public static final String LOG4J_SUBDIRECTORY = "dubbo.log4j.subdirectory";

    public static final String DEFAULT_LOG4J_LEVEL = "ERROR";

    @SuppressWarnings("unchecked")
    public void start() {
        String file = ConfigUtils.getProperty(LOG4J_FILE);
        if (file != null && file.length() > 0) {
            String level = ConfigUtils.getProperty(LOG4J_LEVEL);
            if (level == null || level.length() == 0) {
                level = DEFAULT_LOG4J_LEVEL;
            }
            Properties properties = new Properties();
            properties.setProperty("log4j.rootLogger", level + ",application");
            properties.setProperty("log4j.appender.application", "org.apache.log4j.DailyRollingFileAppender");
            properties.setProperty("log4j.appender.application.File", file);
            properties.setProperty("log4j.appender.application.Append", "true");
            properties.setProperty("log4j.appender.application.DatePattern", "'.'yyyy-MM-dd");
            properties.setProperty("log4j.appender.application.layout", "org.apache.log4j.PatternLayout");
            properties.setProperty("log4j.appender.application.layout.ConversionPattern", "%d [%t] %-5p %C{6} (%F:%L) - %m%n");
            PropertyConfigurator.configure(properties);
        }
        String subdirectory = ConfigUtils.getProperty(LOG4J_SUBDIRECTORY);
        if (subdirectory != null && subdirectory.length() > 0) {
            Enumeration<org.apache.log4j.Logger> ls = LogManager.getCurrentLoggers();
            while (ls.hasMoreElements()) {
                org.apache.log4j.Logger l = ls.nextElement();
                if (l != null) {
                    Enumeration<Appender> as = l.getAllAppenders();
                    while (as.hasMoreElements()) {
                        Appender a = as.nextElement();
                        if (a instanceof FileAppender) {
                            FileAppender fa = (FileAppender) a;
                            String f = fa.getFile();
                            if (f != null && f.length() > 0) {
                                int i = f.replace('\\', '/').lastIndexOf('/');
                                String path;
                                if (i == -1) {
                                    path = subdirectory;
                                } else {
                                    path = f.substring(0, i);
                                    if (!path.endsWith(subdirectory)) {
                                        path = path + "/" + subdirectory;
                                    }
                                    f = f.substring(i + 1);
                                }
                                fa.setFile(path + "/" + f);
                                fa.activateOptions();
                            }
                        }
                    }
                }
            }
        }
    }

    public void stop() {
    }

}

第二种是基于logback:LogbackContainer

package com.alibaba.dubbo.container.logback;

import com.alibaba.dubbo.common.utils.ConfigUtils;
import com.alibaba.dubbo.common.utils.StringUtils;
import com.alibaba.dubbo.container.Container;

import ch.qos.logback.classic.Level;
import ch.qos.logback.classic.Logger;
import ch.qos.logback.classic.LoggerContext;
import ch.qos.logback.classic.encoder.PatternLayoutEncoder;
import ch.qos.logback.classic.spi.ILoggingEvent;
import ch.qos.logback.core.rolling.RollingFileAppender;
import ch.qos.logback.core.rolling.TimeBasedRollingPolicy;
import org.slf4j.LoggerFactory;

/**
 * LogbackContainer. (SPI, Singleton, ThreadSafe)
 */
public class LogbackContainer implements Container {

    public static final String LOGBACK_FILE = "dubbo.logback.file";

    public static final String LOGBACK_LEVEL = "dubbo.logback.level";

    public static final String LOGBACK_MAX_HISTORY = "dubbo.logback.maxhistory";

    public static final String DEFAULT_LOGBACK_LEVEL = "ERROR";

    public void start() {
        String file = ConfigUtils.getProperty(LOGBACK_FILE);
        if (file != null && file.length() > 0) {
            String level = ConfigUtils.getProperty(LOGBACK_LEVEL);
            if (level == null || level.length() == 0) {
                level = DEFAULT_LOGBACK_LEVEL;
            }
            // maxHistory=0 Infinite history
            int maxHistory = StringUtils.parseInteger(ConfigUtils.getProperty(LOGBACK_MAX_HISTORY));

            doInitializer(file, level, maxHistory);
        }
    }

    public void stop() {
    }

    /**
     * Initializer logback
     *
     * @param file
     * @param level
     * @param maxHistory
     */
    private void doInitializer(String file, String level, int maxHistory) {
        LoggerContext loggerContext = (LoggerContext) LoggerFactory.getILoggerFactory();
        Logger rootLogger = loggerContext.getLogger(Logger.ROOT_LOGGER_NAME);
        rootLogger.detachAndStopAllAppenders();

        // appender
        RollingFileAppender<ILoggingEvent> fileAppender = new RollingFileAppender<ILoggingEvent>();
        fileAppender.setContext(loggerContext);
        fileAppender.setName("application");
        fileAppender.setFile(file);
        fileAppender.setAppend(true);

        // policy
        TimeBasedRollingPolicy<ILoggingEvent> policy = new TimeBasedRollingPolicy<ILoggingEvent>();
        policy.setContext(loggerContext);
        policy.setMaxHistory(maxHistory);
        policy.setFileNamePattern(file + ".%d{yyyy-MM-dd}");
        policy.setParent(fileAppender);
        policy.start();
        fileAppender.setRollingPolicy(policy);

        // encoder
        PatternLayoutEncoder encoder = new PatternLayoutEncoder();
        encoder.setContext(loggerContext);
        encoder.setPattern("%date [%thread] %-5level %logger (%file:%line\\) - %msg%n");
        encoder.start();
        fileAppender.setEncoder(encoder);

        fileAppender.start();

        rootLogger.addAppender(fileAppender);
        rootLogger.setLevel(Level.toLevel(level));
        rootLogger.setAdditive(false);
    }

}

第三种是基于spring，这个很重要的:SpringContainer

package com.alibaba.dubbo.container.spring;

import com.alibaba.dubbo.common.logger.Logger;
import com.alibaba.dubbo.common.logger.LoggerFactory;
import com.alibaba.dubbo.common.utils.ConfigUtils;
import com.alibaba.dubbo.container.Container;

import org.springframework.context.support.ClassPathXmlApplicationContext;

/**
 * SpringContainer. (SPI, Singleton, ThreadSafe)
 */
public class SpringContainer implements Container {

    public static final String SPRING_CONFIG = "dubbo.spring.config";
    public static final String DEFAULT_SPRING_CONFIG = "classpath*:META-INF/spring/*.xml";
    private static final Logger logger = LoggerFactory.getLogger(SpringContainer.class);
    static ClassPathXmlApplicationContext context;

    public static ClassPathXmlApplicationContext getContext() {
        return context;
    }

    public void start() {
        String configPath = ConfigUtils.getProperty(SPRING_CONFIG);
        if (configPath == null || configPath.length() == 0) {
            configPath = DEFAULT_SPRING_CONFIG;
        }
        //加载所有spring下面的配置文件,这里也包含了dubbo相关的配置文件
        context = new ClassPathXmlApplicationContext(configPath.split("[,\\s]+"));
        context.start();
    }

    public void stop() {
        try {
            if (context != null) {
                context.stop();
                context.close();
                context = null;
            }
        } catch (Throwable e) {
            logger.error(e.getMessage(), e);
        }
    }

}

然后紧急着还有一个主方法来加在这些容器:Main

package com.alibaba.dubbo.container;

import com.alibaba.dubbo.common.Constants;
import com.alibaba.dubbo.common.extension.ExtensionLoader;
import com.alibaba.dubbo.common.logger.Logger;
import com.alibaba.dubbo.common.logger.LoggerFactory;
import com.alibaba.dubbo.common.utils.ConfigUtils;

import java.text.SimpleDateFormat;
import java.util.ArrayList;
import java.util.Arrays;
import java.util.Date;
import java.util.List;
import java.util.concurrent.locks.Condition;
import java.util.concurrent.locks.ReentrantLock;

/**
 * Main. (API, Static, ThreadSafe)
 */
public class Main {

    public static final String CONTAINER_KEY = "dubbo.container";

    public static final String SHUTDOWN_HOOK_KEY = "dubbo.shutdown.hook";

    private static final Logger logger = LoggerFactory.getLogger(Main.class);

    private static final ExtensionLoader<Container> loader = ExtensionLoader.getExtensionLoader(Container.class);

    private static final ReentrantLock LOCK = new ReentrantLock();

    private static final Condition STOP = LOCK.newCondition();

    public static void main(String[] args) {
        try {
            if (args == null || args.length == 0) {
                String config = ConfigUtils.getProperty(CONTAINER_KEY, loader.getDefaultExtensionName());
                args = Constants.COMMA_SPLIT_PATTERN.split(config);
            }

            final List<Container> containers = new ArrayList<Container>();
            for (int i = 0; i < args.length; i++) {
                //获取所有容器的实例 
                containers.add(loader.getExtension(args[i]));
            }
            logger.info("Use container type(" + Arrays.toString(args) + ") to run dubbo serivce.");

            if ("true".equals(System.getProperty(SHUTDOWN_HOOK_KEY))) {
                Runtime.getRuntime().addShutdownHook(new Thread() {
                    public void run() {
                        for (Container container : containers) {
                            try {
                                container.stop();
                                logger.info("Dubbo " + container.getClass().getSimpleName() + " stopped!");
                            } catch (Throwable t) {
                                logger.error(t.getMessage(), t);
                            }
                            try {
                                LOCK.lock();
                                STOP.signal();
                            } finally {
                                LOCK.unlock();
                            }
                        }
                    }
                });
            }

            for (Container container : containers) {
                //启动所有容器
                container.start();
                logger.info("Dubbo " + container.getClass().getSimpleName() + " started!");
            }
            System.out.println(new SimpleDateFormat("[yyyy-MM-dd HH:mm:ss]").format(new Date()) + " Dubbo service server started!");
        } catch (RuntimeException e) {
            e.printStackTrace();
            logger.error(e.getMessage(), e);
            System.exit(1);
        }
        try {
            LOCK.lock();
            STOP.await();
        } catch (InterruptedException e) {
            logger.warn("Dubbo service server stopped, interrupted by other thread!", e);
        } finally {
            LOCK.unlock();
        }
    }

}