import org.elasticsearch.common.component.LifecycleListener; //导入依赖的package包/类
@Override
protected void doStart() {
    if (logger.isDebugEnabled()) {
        logger.debug("Starting ConfigSyncService");
    }

    if (fileUpdaterEnabled) {
        clusterService.addLifecycleListener(new LifecycleListener() {
            @Override
            public void afterStart() {
                client.admin().cluster().prepareHealth().setWaitForGreenStatus().execute(wrap(res -> {
                    if (res.isTimedOut()) {
                        logger.warn("Cluster service was timeouted.");
                    }
                    checkIfIndexExists(wrap(response -> {
                        final TimeValue time = startUpdater();
                        if (time.millis() >= 0) {
                            logger.info("ConfigFileUpdater is started at {} intervals.", time);
                        }
                    }, e -> {
                        logger.error("Failed to start ConfigFileUpdater.", e);
                    }));
                }, e -> {
                    logger.error("Failed to start ConfigFileUpdater.", e);
                }));
            }
        });
    }
}
 

import org.elasticsearch.common.component.LifecycleListener; //导入依赖的package包/类
@Override
public void addLifecycleListener(LifecycleListener listener) {
    transport.addLifecycleListener(listener);
}
 

import org.elasticsearch.common.component.LifecycleListener; //导入依赖的package包/类
@Override
public void removeLifecycleListener(LifecycleListener listener) {
    transport.removeLifecycleListener(listener);
}
 

import org.elasticsearch.common.component.LifecycleListener; //导入依赖的package包/类
@Override
public void addLifecycleListener(LifecycleListener listener) {
    throw new UnsupportedOperationException();
}
 

import org.elasticsearch.common.component.LifecycleListener; //导入依赖的package包/类
@Override
public void removeLifecycleListener(LifecycleListener listener) {
    throw new UnsupportedOperationException();
}
 

import org.elasticsearch.common.component.LifecycleListener; //导入依赖的package包/类
@Override
public void addLifecycleListener(LifecycleListener listener) {            
}
 

import org.elasticsearch.common.component.LifecycleListener; //导入依赖的package包/类
@Override
public void removeLifecycleListener(LifecycleListener listener) {            
}
 

import org.elasticsearch.common.component.LifecycleListener; //导入依赖的package包/类
@Override
public void addLifecycleListener(LifecycleListener listener) {

}
 

import org.elasticsearch.common.component.LifecycleListener; //导入依赖的package包/类
@Override
public void removeLifecycleListener(LifecycleListener listener) {

}