/**
* JBoss, Home of Professional Open Source
* Copyright 2012, Red Hat, Inc. and individual contributors
* by the @authors tag. See the copyright.txt in the distribution for a
* full listing of individual contributors.
*
* This is free software; you can redistribute it and/or modify it
* under the terms of the GNU Lesser General Public License as
* published by the Free Software Foundation; either version 2.1 of
* the License, or (at your option) any later version.
*
* This software 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
* Lesser General Public License for more details.
*
* You should have received a copy of the GNU Lesser General Public
* License along with this software; if not, write to the Free
* Software Foundation, Inc., 51 Franklin St, Fifth Floor, Boston, MA
* 02110-1301 USA, or see the FSF site: http://www.fsf.org.
*/
package org.jboss.arquillian.graphene.page.extension;
import java.util.ArrayList;
import java.util.List;
import org.jboss.arquillian.core.spi.Validate;
import org.jboss.arquillian.graphene.spi.page.PageExtension;
/**
* @author <a href="mailto:jpapouse@redhat.com">Jan Papousek</a>
*/
public abstract class AbstractPageExtensionInstallatorProvider implements PageExtensionInstallatorProvider {
private final PageExtensionRegistry registry;
public AbstractPageExtensionInstallatorProvider(PageExtensionRegistry registry) {
Validate.notNull(registry, "registry should not be null");
this.registry = registry;
}
@Override
public final PageExtensionInstallator installator(String name) {
return installator(name, true);
}
@Override
public final PageExtensionInstallator installator(String name, boolean checkRequirements) {
PageExtension extension = getRegistry().getExtension(name);
if (extension == null) {
return null;
}
if (checkRequirements) {
checkRequirements(name);
}
return createInstallator(extension);
}
protected final PageExtensionRegistry getRegistry() {
return registry;
}
private void checkRequirements(String extensionName) {
List<String> stack = new ArrayList<String>();
stack.add(extensionName);
checkRequirements(stack);
}
private void checkRequirements(List<String> stack) {
PageExtension top = getRegistry().getExtension(stack.get(stack.size()-1));
if (top == null) {
throw new IllegalArgumentException("There is no registered extension '"+stack.get(stack.size()-1)+"'.");
}
for (String requiredName: top.getRequired()) {
PageExtension required = getRegistry().getExtension(requiredName);
for (String onStack: stack) {
if (required.getName().equals(onStack)) {
throw new IllegalStateException("There is a cycle in page extension requirements, DFS stack: " + stack);
}
}
stack.add(required.getName());
checkRequirements(stack);
}
stack.remove(stack.size()-1);
}
public abstract PageExtensionInstallator createInstallator(PageExtension extension);
}