logback的ShutdownHook關閉原理解析

更新時間：2023年11月09日 08:36:50 作者：codecraft

這篇文章主要為大家介紹了logback的ShutdownHook關閉原理源碼解讀，有需要的朋友可以借鑒參考下，希望能夠有所幫助，祝大家多多進步，早日升職加薪

序

本文主要研究一下logback的ShutdownHook

ShutdownHook

ch/qos/logback/core/hook/ShutdownHook.java

/**
 * Interface describing a logback shutdown hook implementation
 * 
 * @author Mike Reinhold
 */
public interface ShutdownHook extends Runnable, ContextAware {
}

ShutdownHook接口繼承了Runnable、ContextAware接口

ShutdownHookBase

ch/qos/logback/core/hook/ShutdownHookBase.java

/**
 * Base class for classes implementing a Logback ShutdownHook via extension
 *
 * @author Mike Reinhold
 */
public abstract class ShutdownHookBase extends ContextAwareBase implements ShutdownHook {
    public ShutdownHookBase() {
    }
    /**
     * Default method for stopping the Logback context
     */
    protected void stop() {
        addInfo("Logback context being closed via shutdown hook");
        Context hookContext = getContext();
        if (hookContext instanceof ContextBase) {
            ContextBase context = (ContextBase) hookContext;
            context.stop();
        }
    }
}

ShutdownHookBase繼承了ContextAwareBase，聲明實現(xiàn)ShutdownHook，它提供了一個stop方法，用于關閉ContextBase

DelayingShutdownHook

ch/qos/logback/core/hook/DelayingShutdownHook.java

/**
 * ShutdownHook implementation that stops the Logback context after a specified
 * delay.  The default delay is 0 ms (zero).
 *
 * @author Mike Reinhold
 */
public class DelayingShutdownHook extends ShutdownHookBase {
    /**
     * The default is no delay before shutdown.
     */
    public static final Duration DEFAULT_DELAY = Duration.buildByMilliseconds(0);
    /**
     * The delay in milliseconds before the ShutdownHook stops the logback context
     */
    private Duration delay = DEFAULT_DELAY;
    public DelayingShutdownHook() {
    }
    public Duration getDelay() {
        return delay;
    }
    /**
     * The duration to wait before shutting down the current logback context.
     *
     * @param delay
     */
    public void setDelay(Duration delay) {
        this.delay = delay;
    }
    public void run() {
        addInfo("Sleeping for "+delay);
        try {
            Thread.sleep(delay.getMilliseconds());
        } catch (InterruptedException e) {
        }
        super.stop();
    }
}

DelayingShutdownHook繼承了ShutdownHookBase，其run方法先sleep指定的delay，然后執(zhí)行stop方法

示例

<configuration debug="false">
    <shutdownHook class="ch.qos.logback.core.hook.DelayingShutdownHook">
        <delay>10</delay>
    </shutdownHook>
    <appender name="A" class="ch.qos.logback.core.read.ListAppender"/>
    <root level="DEBUG">
        <appender-ref ref="A" />
    </root>
</configuration>