package org.jtheque.modules.impl;
/*
* Copyright JTheque (Baptiste Wicht)
*
* Licensed 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.
*/
import org.jtheque.modules.Module;
import org.jtheque.utils.StringUtils;
import org.jtheque.utils.collections.ArrayUtils;
import java.io.Serializable;
import java.util.Comparator;
/**
* A comparator for modules. Sort the modules in the order they need to be launched.
*
* @author Baptiste Wicht
*/
final class ModuleComparator implements Comparator<Module>, Serializable {
private static final long serialVersionUID = 2805880990486998739L;
@Override
public int compare(Module o1, Module o2) {
boolean hasDependency = hasDependency(o1);
boolean hasOtherDependency = hasDependency(o2);
if (hasDependency && !hasOtherDependency) {
return 1;
} else if (!hasDependency && hasOtherDependency) {
return -1;
} else {
//The other depends on me
if (ArrayUtils.contains(o2.getDependencies(), o1.getId())) {
return -1;
}
//I depends on the other
if (ArrayUtils.contains(o1.getDependencies(), o2.getId())) {
return 1;
}
}
return 0;
}
/**
* Indicate if the module has dependency or not.
*
* @param module The module to test.
*
* @return true if the module has dependency else false.
*/
private static boolean hasDependency(Module module) {
return StringUtils.isNotEmpty(module.getDependencies());
}
}