com.nextep.datadesigner.vcs.impl.VersionableSorter.java Source code

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Here is the source code for com.nextep.datadesigner.vcs.impl.VersionableSorter.java

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/*******************************************************************************
 * Copyright (c) 2011 neXtep Software and contributors.
 * All rights reserved.
 *
 * This file is part of neXtep designer.
 *
 * NeXtep designer 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 any later version.
 *
 * NeXtep designer 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 Foobar.  If not, see <http://www.gnu.org/licenses/>.
 *
 * Contributors:
 *     neXtep Softwares - initial API and implementation
 *******************************************************************************/
package com.nextep.datadesigner.vcs.impl;

import java.util.ArrayList;
import java.util.Collection;
import java.util.Comparator;
import java.util.HashMap;
import java.util.List;
import java.util.Map;
import org.apache.commons.logging.Log;
import org.apache.commons.logging.LogFactory;
import com.nextep.datadesigner.model.IReference;
import com.nextep.designer.vcs.model.IVersionable;

public class VersionableSorter implements Comparator<IVersionable<?>> {

    private static final Log log = LogFactory.getLog(VersionableSorter.class);

    @Override
    public int compare(IVersionable<?> o1, IVersionable<?> o2) {
        // Putting dependencies first
        if (containsAny(o1.getReferenceDependencies(), o2.getReferenceMap().keySet())) {
            return 1;
        } else if (containsAny(o2.getReferenceDependencies(), o1.getReferenceMap().keySet())) {
            return -1;
        } else {
            // We only put tables first
            if ("TABLE".equals(o1.getType().getId()) && "TABLE".equals(o2.getType().getId())) {
                return -1;
            } else if ("TABLE".equals(o1.getType().getId())) {
                return -1;
            } else if ("TABLE".equals(o2.getType().getId())) {
                return 1;
            } else {
                return o1.getName().compareTo(o2.getName());
            }
        }
    }

    private boolean containsAny(Collection<?> lookup, Collection<?> contained) {
        for (Object o : contained) {
            if (lookup.contains(o)) {
                return true;
            }
        }
        return false;
    }

    public static List<IVersionable<?>> sort(Collection<IVersionable<?>> list) {
        List<IVersionable<?>> sortedList = new ArrayList<IVersionable<?>>();
        Map<IReference, IVersionable<?>> invRefMap = new HashMap<IReference, IVersionable<?>>();
        for (IVersionable<?> v : list) {
            invRefMap.put(v.getReference(), v);
            for (IReference r : v.getReferenceMap().keySet()) {
                invRefMap.put(r, v);
            }
        }
        for (IVersionable<?> v : list) {
            processItem(sortedList, invRefMap, v, new ArrayList<IVersionable<?>>());
        }
        return sortedList;
    }

    private static void processItem(List<IVersionable<?>> sortedList, Map<IReference, IVersionable<?>> invRefMap,
            IVersionable<?> toAdd, Collection<IVersionable<?>> stack) {
        Collection<IReference> refs = toAdd.getReferenceDependencies();
        Collection<IReference> ownReferences = toAdd.getReferenceMap().keySet();
        // If the stack already contains the versionable to add, dependency deadloop !
        // We stop the process here
        if (stack.contains(toAdd)) {
            log.warn("Deadloop found in schema inner dependencies: unsafe dependency resolution.");
            return;
        }
        stack.add(toAdd);
        for (IReference r : refs) {
            final IVersionable<?> v = invRefMap.get(r);
            if (v != null && !sortedList.contains(v) && !ownReferences.contains(r) && toAdd.getReference() != r) {
                processItem(sortedList, invRefMap, v, stack);
            }
        }
        stack.remove(toAdd);
        // Might have already been imported
        if (!sortedList.contains(toAdd)) {
            sortedList.add(toAdd);
        }
    }
}