spring boot 集成 log4j2，MDC如何设置

MDC改用ThreadContext，原文：org.apache.log4j.MDC and org.apache.log4j.NDC have been replaced by the Thread
Context.

import org.apache.commons.lang.StringUtils;
import org.apache.logging.log4j.ThreadContext;
import org.springframework.boot.SpringApplication;
import org.springframework.boot.context.event.*;
import org.springframework.context.ApplicationContext;
import org.springframework.context.ApplicationEvent;
import org.springframework.context.event.ContextClosedEvent;
import org.springframework.context.event.GenericApplicationListener;
import org.springframework.core.Ordered;
import org.springframework.core.ResolvableType;
import org.springframework.core.env.ConfigurableEnvironment;
import org.springframework.core.env.MutablePropertySources;
import org.springframework.core.env.PropertySource;

/**
 * @author wsf 2019/7/9
 */
public class ApplicationStartedEventListener implements GenericApplicationListener {
    private static final int DEFAULT_ORDER = Ordered.HIGHEST_PRECEDENCE + 10;

    private static Class<?>[] EVENT_TYPES = {ApplicationStartingEvent.class,
            ApplicationEnvironmentPreparedEvent.class, ApplicationPreparedEvent.class,
            ContextClosedEvent.class, ApplicationFailedEvent.class};

    private static Class<?>[] SOURCE_TYPES = {SpringApplication.class,
            ApplicationContext.class};
 
    @Override
    public void onApplicationEvent(ApplicationEvent event) {
        if (event instanceof ApplicationEnvironmentPreparedEvent) {
            ConfigurableEnvironment envi = ((ApplicationEnvironmentPreparedEvent) event).getEnvironment();
            MutablePropertySources mps = envi.getPropertySources();

            PropertySource<?> ps = mps.get("applicationConfig: [classpath:/application.yml]");

            if(ps != null && ps.containsProperty("spring.application.name")) {
                String appName = (String) ps.getProperty("spring.application.name");
                if (StringUtils.isNotBlank(appName)) {
                    ThreadContext.put("appName", appName);
                }
            }
            String profile = envi.getActiveProfiles()[0];
            if (StringUtils.isNotBlank(profile)) {
                ThreadContext.put("profile", profile);
            }
        }
    }

    @Override
    public int getOrder() {
        // 设置加载优先级，在日志之前加载
        return DEFAULT_ORDER;
    }

    @Override
    public boolean supportsEventType(ResolvableType resolvableType) {
        return isAssignableFrom(resolvableType.getRawClass(), EVENT_TYPES);
    }

    @Override
    public boolean supportsSourceType(Class<?> sourceType) {
        return isAssignableFrom(sourceType, SOURCE_TYPES);
    }

    private boolean isAssignableFrom(Class<?> type, Class<?>... supportedTypes) {
        if (type != null) {
            for (Class<?> supportedType : supportedTypes) {
                if (supportedType.isAssignableFrom(type)) {
                    return true;
                }
            }
        }
        return false;
    }
}