/*
* 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.felix.ipojo.handlers.lifecycle.callback;
import java.lang.reflect.InvocationTargetException;
import java.util.Dictionary;
import org.apache.felix.ipojo.ComponentInstance;
import org.apache.felix.ipojo.ConfigurationException;
import org.apache.felix.ipojo.InstanceManager;
import org.apache.felix.ipojo.PrimitiveHandler;
import org.apache.felix.ipojo.metadata.Element;
import org.apache.felix.ipojo.parser.MethodMetadata;
import org.apache.felix.ipojo.parser.PojoMetadata;
/**
* Lifecycle callback handler.
*
* @author <a href="mailto:dev@felix.apache.org">Felix Project Team</a>
*/
public class LifecycleCallbackHandler extends PrimitiveHandler {
/**
* The list of the callback of the component.
*/
private LifecycleCallback[] m_callbacks = new LifecycleCallback[0];
/**
* State of the instance manager (unresolved at the beginning).
*/
private int m_state = InstanceManager.INVALID;
/**
* Does a POJO object be created at starting.
*/
private boolean m_immediate = false;
/**
* Add the given callback to the callback list.
*
* @param callback : the element to add
*/
private void addCallback(LifecycleCallback callback) {
for (int i = 0; (m_callbacks != null) && (i < m_callbacks.length); i++) {
if (m_callbacks[i] == callback) {
return;
}
}
if (m_callbacks != null && m_callbacks.length > 0) { //TODO check here if we can improve the test
LifecycleCallback[] newHk = new LifecycleCallback[m_callbacks.length + 1];
System.arraycopy(m_callbacks, 0, newHk, 0, m_callbacks.length);
newHk[m_callbacks.length] = callback;
m_callbacks = newHk;
} else {
m_callbacks = new LifecycleCallback[] { callback };
}
}
/**
* Configure the handler.
* @param metadata : the component type metadata
* @param configuration : the instance configuration
* @throws ConfigurationException : one callback metadata is not correct (either the transition or the method are not correct).
* @see org.apache.felix.ipojo.Handler#configure(org.apache.felix.ipojo.InstanceManager, org.apache.felix.ipojo.metadata.Element, java.util.Dictionary)
*/
public void configure(Element metadata, Dictionary configuration) throws ConfigurationException {
m_callbacks = new LifecycleCallback[0];
String imm = metadata.getAttribute("immediate");
m_immediate = imm != null && imm.equalsIgnoreCase("true");
PojoMetadata meta = getFactory().getPojoMetadata();
Element[] hooksMetadata = metadata.getElements("callback");
for (int i = 0; hooksMetadata != null && i < hooksMetadata.length; i++) {
String method = hooksMetadata[i].getAttribute("method");
if (method == null) {
throw new ConfigurationException("Lifecycle callback : A callback needs to contain a method attribute");
}
MethodMetadata met = meta.getMethod(method, new String[0]);
int transition = -1;
String trans = hooksMetadata[i].getAttribute("transition");
if (trans == null) {
throw new ConfigurationException("Lifecycle callback : the transition attribute is missing");
} else {
if (trans.equalsIgnoreCase("validate")) {
transition = LifecycleCallback.VALIDATE;
} else if (trans.equalsIgnoreCase("invalidate")) {
transition = LifecycleCallback.INVALIDATE;
} else {
throw new ConfigurationException("Lifecycle callback : Unknown or malformed transition : " + trans);
}
}
LifecycleCallback callback = null;
if (met == null) {
callback = new LifecycleCallback(this, transition, method);
} else {
callback = new LifecycleCallback(this, transition, met);
}
addCallback(callback);
}
}
/**
* Start the handler.
* @see org.apache.felix.ipojo.Handler#start()
*/
public void start() {
// Do nothing during the start
}
/**
* Stop the handler.
* @see org.apache.felix.ipojo.Handler#stop()
*/
public void stop() {
m_state = InstanceManager.INVALID;
}
/**
* When the state change call the associated callback.
*
* @param state : the new instance state.
* @see org.apache.felix.ipojo.Handler#stateChanged(int)
*/
public void stateChanged(int state) {
int transition = -1;
if (m_state == ComponentInstance.INVALID && state == ComponentInstance.VALID) {
transition = LifecycleCallback.VALIDATE;
}
if (m_state == ComponentInstance.VALID && state == ComponentInstance.INVALID) {
transition = LifecycleCallback.INVALIDATE;
}
// Manage immediate component
if (m_immediate && transition == LifecycleCallback.VALIDATE && getInstanceManager().getPojoObjects() == null) {
getInstanceManager().getPojoObject();
}
for (int i = 0; i < m_callbacks.length; i++) {
if (m_callbacks[i].getTransition() == transition) {
try {
m_callbacks[i].call();
} catch (NoSuchMethodException e) {
error("[" + getInstanceManager().getInstanceName() + "] The callback method " + m_callbacks[i].getMethod() + " is not found");
throw new IllegalStateException(e.getMessage());
} catch (IllegalAccessException e) {
error("[" + getInstanceManager().getInstanceName() + "] The callback method " + m_callbacks[i].getMethod() + " is not accessible");
throw new IllegalStateException(e.getMessage());
} catch (InvocationTargetException e) {
error("[" + getInstanceManager().getInstanceName() + "] The callback method " + m_callbacks[i].getMethod() + " has thrown an exception : " + e.getTargetException().getMessage(), e.getTargetException());
throw new IllegalStateException(e.getTargetException().getMessage());
}
}
}
// Update to internal state
m_state = state;
}
}