org.mycore.common.events.MCRStartupHandler Maven / Gradle / Ivy
/*
* This file is part of *** M y C o R e ***
* See http://www.mycore.de/ for details.
*
* MyCoRe is free software: you can redistribute it and/or modify
* it under the terms of the GNU General Public License as published by
* the Free Software Foundation, either version 3 of the License, or
* (at your option) any later version.
*
* MyCoRe is distributed in the hope that it will be useful,
* but WITHOUT ANY WARRANTY; without even the implied warranty of
* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
* GNU General Public License for more details.
*
* You should have received a copy of the GNU General Public License
* along with MyCoRe. If not, see .
*/
package org.mycore.common.events;
import java.util.stream.Stream;
import javax.servlet.ServletContext;
import org.apache.logging.log4j.LogManager;
import org.apache.logging.log4j.Logger;
import org.mycore.common.MCRClassTools;
import org.mycore.common.config.MCRConfiguration2;
import org.mycore.common.config.MCRConfigurationDirSetup;
import org.mycore.common.config.MCRConfigurationException;
import org.mycore.common.config.MCRRuntimeComponentDetector;
import org.mycore.common.xml.MCRURIResolver;
/**
* Initializes classes that implement {@link AutoExecutable} interface that are defined via
* MCR.Startup.Class
property.
*
* @author Thomas Scheffler (yagee)
*/
public class MCRStartupHandler {
/**
* Can set true
or false
as {@link ServletContext#setAttribute(String, Object)} to skip
* errors on startup.
*/
public static final String HALT_ON_ERROR = "MCR.Startup.haltOnError";
private static final Logger LOGGER = LogManager.getLogger();
private static boolean isWebApp;
public static void startUp(ServletContext servletContext) {
//setup configuration
MCRConfigurationDirSetup dirSetup = new MCRConfigurationDirSetup();
dirSetup.startUp(servletContext);
isWebApp = servletContext != null;
//initialize ClassLoader here, so it can be used later reliably.
MCRClassTools.updateClassLoader();
ClassLoader resourceClassLoader = MCRClassTools.getClassLoader();
LOGGER.info("The following ClassLoader is used: {}", resourceClassLoader);
LOGGER.info("I have these components for you: {}", MCRRuntimeComponentDetector.getAllComponents());
LOGGER.info("I have these mycore components for you: {}", MCRRuntimeComponentDetector.getMyCoReComponents());
LOGGER.info("I have these app modules for you: {}", MCRRuntimeComponentDetector.getApplicationModules());
if (servletContext != null) {
LOGGER.info("Library order: {}", servletContext.getAttribute(ServletContext.ORDERED_LIBS));
}
MCRConfiguration2.getString("MCR.Startup.Class")
.map(MCRConfiguration2::splitValue)
.orElseGet(Stream::empty)
.map(MCRStartupHandler::getAutoExecutable)
//reverse ordering: highest priority first
.sorted((o1, o2) -> Integer.compare(o2.getPriority(), o1.getPriority()))
.forEachOrdered(autoExecutable -> startExecutable(servletContext, autoExecutable));
//initialize MCRURIResolver
MCRURIResolver.init(servletContext);
}
public static boolean isWebApp() {
return isWebApp;
}
private static void startExecutable(ServletContext servletContext, AutoExecutable autoExecutable) {
LOGGER.info("{}: Starting {}", autoExecutable.getPriority(), autoExecutable.getName());
try {
autoExecutable.startUp(servletContext);
} catch (ExceptionInInitializerError | RuntimeException e) {
boolean haltOnError = servletContext == null || servletContext.getAttribute(HALT_ON_ERROR) == null
|| Boolean.parseBoolean((String) servletContext.getAttribute(HALT_ON_ERROR));
if (haltOnError) {
throw e;
}
LOGGER.warn(e.toString());
}
}
private static AutoExecutable getAutoExecutable(String className) {
try {
return (AutoExecutable) MCRClassTools.forName(className).getDeclaredConstructor().newInstance();
} catch (ReflectiveOperationException e) {
throw new MCRConfigurationException("Could not initialize 'MCR.Startup.Class': " + className, e);
}
}
public interface AutoExecutable {
/**
* returns a name to display on start-up.
*/
String getName();
/**
* If order is important returns as 'heigher' priority.
*/
int getPriority();
/**
* This method get executed by {@link MCRStartupHandler#startUp(ServletContext)}
*/
void startUp(ServletContext servletContext);
}
}