org.apache.log4j.jmx.LayoutDynamicMBean Maven / Gradle / Ivy

Go to download
Show more of this group Show more artifacts with this name
Show all versions of reload4j Show documentation
Reload4j revives EOLed log4j 1.x
There is a newer version: 1.2.25
/*
 * Licensed to the Apache Software Foundation (ASF) under one or more
 * contributor license agreements.  See the NOTICE file distributed with
 * this work for additional information regarding copyright ownership.
 * The ASF licenses this file to You under the Apache License, Version 2.0
 * (the "License"); you may not use this file except in compliance with
 * the License.  You may obtain a copy of the License at
 * 
 *      http://www.apache.org/licenses/LICENSE-2.0
 * 
 * Unless required by applicable law or agreed to in writing, software
 * distributed under the License is distributed on an "AS IS" BASIS,
 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
 * See the License for the specific language governing permissions and
 * limitations under the License.
 */

package org.apache.log4j.jmx;

import java.lang.reflect.Constructor;
import org.apache.log4j.Logger;
import org.apache.log4j.Level;
import org.apache.log4j.Layout;
import org.apache.log4j.helpers.OptionConverter;
import org.apache.log4j.spi.OptionHandler;

import java.util.Vector;
import java.util.Hashtable;
import java.lang.reflect.Method;
import java.lang.reflect.InvocationTargetException;
import javax.management.MBeanAttributeInfo;
import javax.management.MBeanConstructorInfo;
import javax.management.MBeanNotificationInfo;
import javax.management.MBeanInfo;
import javax.management.Attribute;

import javax.management.MBeanException;
import javax.management.AttributeNotFoundException;
import javax.management.RuntimeOperationsException;
import javax.management.ReflectionException;
import javax.management.InvalidAttributeValueException;
import javax.management.MBeanOperationInfo;
import javax.management.MBeanParameterInfo;

import java.beans.Introspector;
import java.beans.BeanInfo;
import java.beans.PropertyDescriptor;
import java.beans.IntrospectionException;
import java.io.InterruptedIOException;

public class LayoutDynamicMBean extends AbstractDynamicMBean {

    private MBeanConstructorInfo[] dConstructors = new MBeanConstructorInfo[1];
    private Vector dAttributes = new Vector();
    private String dClassName = this.getClass().getName();

    private Hashtable dynamicProps = new Hashtable(5);
    private MBeanOperationInfo[] dOperations = new MBeanOperationInfo[1];
    private String dDescription = "This MBean acts as a management facade for log4j layouts.";

    // This category instance is for logging.
    private static Logger cat = Logger.getLogger(LayoutDynamicMBean.class);

    // We wrap this layout instance.
    private Layout layout;

    public LayoutDynamicMBean(Layout layout) throws IntrospectionException {
	this.layout = layout;
	buildDynamicMBeanInfo();
    }

    private void buildDynamicMBeanInfo() throws IntrospectionException {
	Constructor[] constructors = this.getClass().getConstructors();
	dConstructors[0] = new MBeanConstructorInfo("LayoutDynamicMBean(): Constructs a LayoutDynamicMBean instance",
		constructors[0]);

	BeanInfo bi = Introspector.getBeanInfo(layout.getClass());
	PropertyDescriptor[] pd = bi.getPropertyDescriptors();

	int size = pd.length;

	for (int i = 0; i < size; i++) {
	    String name = pd[i].getName();
	    Method readMethod = pd[i].getReadMethod();
	    Method writeMethod = pd[i].getWriteMethod();
	    if (readMethod != null) {
		Class returnClass = readMethod.getReturnType();
		if (isSupportedType(returnClass)) {
		    String returnClassName;
		    if (returnClass.isAssignableFrom(Level.class)) {
			returnClassName = "java.lang.String";
		    } else {
			returnClassName = returnClass.getName();
		    }

		    dAttributes.add(
			    new MBeanAttributeInfo(name, returnClassName, "Dynamic", true, writeMethod != null, false));
		    dynamicProps.put(name, new MethodUnion(readMethod, writeMethod));
		}
	    }
	}

	MBeanParameterInfo[] params = new MBeanParameterInfo[0];

	dOperations[0] = new MBeanOperationInfo("activateOptions", "activateOptions(): add an layout", params, "void",
		MBeanOperationInfo.ACTION);
    }

    private boolean isSupportedType(Class clazz) {
	if (clazz.isPrimitive()) {
	    return true;
	}

	if (clazz == String.class) {
	    return true;
	}
	if (clazz.isAssignableFrom(Level.class)) {
	    return true;
	}

	return false;
    }

    public MBeanInfo getMBeanInfo() {
	cat.debug("getMBeanInfo called.");

	MBeanAttributeInfo[] attribs = new MBeanAttributeInfo[dAttributes.size()];
	dAttributes.toArray(attribs);

	return new MBeanInfo(dClassName, dDescription, attribs, dConstructors, dOperations,
		new MBeanNotificationInfo[0]);
    }

    public Object invoke(String operationName, Object params[], String signature[])
	    throws MBeanException, ReflectionException {

	if (operationName.equals("activateOptions") && layout instanceof OptionHandler) {
	    OptionHandler oh = (OptionHandler) layout;
	    oh.activateOptions();
	    return "Options activated.";
	}
	return null;
    }

    protected Logger getLogger() {
	return cat;
    }

    public Object getAttribute(String attributeName)
	    throws AttributeNotFoundException, MBeanException, ReflectionException {

	// Check attributeName is not null to avoid NullPointerException later on
	if (attributeName == null) {
	    throw new RuntimeOperationsException(new IllegalArgumentException("Attribute name cannot be null"),
		    "Cannot invoke a getter of " + dClassName + " with null attribute name");
	}

	MethodUnion mu = (MethodUnion) dynamicProps.get(attributeName);

	cat.debug("----name=" + attributeName + ", mu=" + mu);

	if (mu != null && mu.readMethod != null) {
	    try {
		return mu.readMethod.invoke(layout, null);
	    } catch (InvocationTargetException e) {
		if (e.getTargetException() instanceof InterruptedException
			|| e.getTargetException() instanceof InterruptedIOException) {
		    Thread.currentThread().interrupt();
		}
		return null;
	    } catch (IllegalAccessException e) {
		return null;
	    } catch (RuntimeException e) {
		return null;
	    }
	}

	// If attributeName has not been recognized throw an AttributeNotFoundException
	throw (new AttributeNotFoundException("Cannot find " + attributeName + " attribute in " + dClassName));

    }

    public void setAttribute(Attribute attribute)
	    throws AttributeNotFoundException, InvalidAttributeValueException, MBeanException, ReflectionException {

	// Check attribute is not null to avoid NullPointerException later on
	if (attribute == null) {
	    throw new RuntimeOperationsException(new IllegalArgumentException("Attribute cannot be null"),
		    "Cannot invoke a setter of " + dClassName + " with null attribute");
	}
	String name = attribute.getName();
	Object value = attribute.getValue();

	if (name == null) {
	    throw new RuntimeOperationsException(new IllegalArgumentException("Attribute name cannot be null"),
		    "Cannot invoke the setter of " + dClassName + " with null attribute name");
	}

	MethodUnion mu = (MethodUnion) dynamicProps.get(name);

	if (mu != null && mu.writeMethod != null) {
	    Object[] o = new Object[1];

	    Class[] params = mu.writeMethod.getParameterTypes();
	    if (params[0] == org.apache.log4j.Priority.class) {
		value = OptionConverter.toLevel((String) value, (Level) getAttribute(name));
	    }
	    o[0] = value;

	    try {
		mu.writeMethod.invoke(layout, o);

	    } catch (InvocationTargetException e) {
		if (e.getTargetException() instanceof InterruptedException
			|| e.getTargetException() instanceof InterruptedIOException) {
		    Thread.currentThread().interrupt();
		}
		cat.error("FIXME", e);
	    } catch (IllegalAccessException e) {
		cat.error("FIXME", e);
	    } catch (RuntimeException e) {
		cat.error("FIXME", e);
	    }
	} else {
	    throw (new AttributeNotFoundException("Attribute " + name + " not found in " + this.getClass().getName()));
	}
    }
}