psiprobe.tools.logging.log4j.Log4JManagerAccessor.java Source code

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Here is the source code for psiprobe.tools.logging.log4j.Log4JManagerAccessor.java

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/**
 * Licensed under the GPL License. You may not use this file except in compliance with the License.
 * You may obtain a copy of the License at
 *
 *   http://www.gnu.org/licenses/old-licenses/gpl-2.0.html
 *
 * THIS PACKAGE IS PROVIDED "AS IS" AND WITHOUT ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING,
 * WITHOUT LIMITATION, THE IMPLIED WARRANTIES OF MERCHANTIBILITY AND FITNESS FOR A PARTICULAR
 * PURPOSE.
 */
package psiprobe.tools.logging.log4j;

import org.apache.commons.beanutils.MethodUtils;

import psiprobe.tools.logging.DefaultAccessor;

import java.lang.reflect.Method;
import java.util.ArrayList;
import java.util.Collections;
import java.util.Enumeration;
import java.util.List;

/**
 * The Class Log4JManagerAccessor.
 */
public class Log4JManagerAccessor extends DefaultAccessor {

    /**
     * Instantiates a new log4 j manager accessor.
     *
     * @param cl the cl
     * @throws ClassNotFoundException the class not found exception
     */
    public Log4JManagerAccessor(ClassLoader cl) throws ClassNotFoundException {
        Class clazz = cl.loadClass("org.apache.log4j.LogManager");
        Method exists = MethodUtils.getAccessibleMethod(clazz, "exists", new Class[] { String.class });
        if (exists == null) {
            throw new RuntimeException("The LogManager is part of the slf4j bridge.");
        }
        setTarget(clazz);
    }

    /**
     * Gets the root logger.
     *
     * @return the root logger
     */
    public Log4JLoggerAccessor getRootLogger() {
        try {
            Class clazz = (Class) getTarget();
            Method getRootLogger = MethodUtils.getAccessibleMethod(clazz, "getRootLogger", new Class[0]);

            Object logger = getRootLogger.invoke(null);
            if (logger == null) {
                throw new NullPointerException(getTarget().getClass().getName() + "#getRootLogger() returned null");
            }
            Log4JLoggerAccessor accessor = new Log4JLoggerAccessor();
            accessor.setTarget(logger);
            accessor.setApplication(getApplication());
            return accessor;
        } catch (Exception e) {
            logger.error("{}#getRootLogger() failed", getTarget().getClass().getName(), e);
        }
        return null;
    }

    /**
     * Gets the logger.
     *
     * @param name the name
     * @return the logger
     */
    public Log4JLoggerAccessor getLogger(String name) {
        try {
            Class clazz = (Class) getTarget();
            Method getLogger = MethodUtils.getAccessibleMethod(clazz, "getLogger", new Class[] { String.class });

            Object logger = getLogger.invoke(null, name);
            if (logger == null) {
                throw new NullPointerException(
                        getTarget().getClass().getName() + "#getLogger(\"" + name + "\") returned null");
            }
            Log4JLoggerAccessor accessor = new Log4JLoggerAccessor();
            accessor.setTarget(logger);
            accessor.setApplication(getApplication());
            return accessor;
        } catch (Exception e) {
            logger.error("{}#getLogger('{}') failed", getTarget().getClass().getName(), name, e);
        }
        return null;
    }

    /**
     * Gets the appenders.
     *
     * @return the appenders
     */
    public List<Log4JAppenderAccessor> getAppenders() {
        List<Log4JAppenderAccessor> appenders = new ArrayList<>();
        try {
            appenders.addAll(getRootLogger().getAppenders());

            Class clazz = (Class) getTarget();
            Method getCurrentLoggers = MethodUtils.getAccessibleMethod(clazz, "getCurrentLoggers", new Class[0]);

            for (Object currentLogger : Collections.list((Enumeration<Object>) getCurrentLoggers.invoke(null))) {
                Log4JLoggerAccessor accessor = new Log4JLoggerAccessor();
                accessor.setTarget(currentLogger);
                accessor.setApplication(getApplication());

                appenders.addAll(accessor.getAppenders());
            }
        } catch (Exception e) {
            logger.error("{}#getCurrentLoggers() failed", getTarget().getClass().getName(), e);
        }
        return appenders;
    }

}