org.springframework.ide.eclipse.boot.wizard.PopularityTracker.java Source code

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Here is the source code for org.springframework.ide.eclipse.boot.wizard.PopularityTracker.java

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/*******************************************************************************
 * Copyright (c) 2012 Pivotal Software, Inc.
 * All rights reserved. This program and the accompanying materials
 * are made available under the terms of the Eclipse Public License v1.0
 * which accompanies this distribution, and is available at
 * https://www.eclipse.org/legal/epl-v10.html
 *
 * Contributors:
 *    Pivotal Software, Inc. - initial API and implementation
 *******************************************************************************/
package org.springframework.ide.eclipse.boot.wizard;

import java.util.ArrayList;
import java.util.Collection;
import java.util.Collections;
import java.util.Comparator;
import java.util.HashMap;
import java.util.Iterator;
import java.util.List;
import java.util.Map;

import org.eclipse.jface.preference.IPreferenceStore;
import org.springframework.ide.eclipse.boot.core.initializr.InitializrServiceSpec.Dependency;
import org.springframework.ide.eclipse.boot.wizard.CheckBoxesSection.CheckBoxModel;

/**
 * Component that keeps track of 'popular' dependencies used in the NewSpringBootWizard.
 * It keeps a persistent count of how many times a given dependency has been used.
 *
 * @author Kris De Volder
 */
public class PopularityTracker {

    public static final String PREFIX = PopularityTracker.class.getName() + ".";

    private IPreferenceStore store;

    public PopularityTracker(IPreferenceStore store) {
        this.store = store;
    }

    protected String key(String id) {
        String key = PREFIX + id;
        return key;
    }

    public void incrementUsageCount(Dependency d) {
        incrementUsageCount(d.getId());
    }

    public int getUsageCount(Dependency d) {
        return getUsageCount(d.getId());
    }

    public int getUsageCount(String id) {
        return store.getInt(key(id));
    }

    private void incrementUsageCount(String id) {
        String key = key(id);
        store.setValue(key, store.getInt(key) + 1);
    }

    public void incrementUsageCount(Collection<Dependency> selected) {
        for (Dependency d : selected) {
            incrementUsageCount(d);
        }
    }

    public List<CheckBoxModel<Dependency>> getMostPopular(
            HierarchicalMultiSelectionFieldModel<Dependency> dependencies, int howMany) {
        final Map<CheckBoxModel<Dependency>, Integer> useCounts = new HashMap<CheckBoxModel<Dependency>, Integer>(); //usecounts by dependency id

        ArrayList<CheckBoxModel<Dependency>> allUsedBoxes = new ArrayList<CheckBoxModel<Dependency>>();
        for (String category : dependencies.getCategories()) {
            allUsedBoxes.addAll(dependencies.getContents(category).getCheckBoxModels());
        }

        for (Iterator<CheckBoxModel<Dependency>> iterator = allUsedBoxes.iterator(); iterator.hasNext();) {
            CheckBoxModel<Dependency> cb = iterator.next();
            int useCount = this.getUsageCount(cb.getValue());
            if (useCount == 0) {
                iterator.remove(); //don't care about those options never used at all.
            } else {
                useCounts.put(cb, this.getUsageCount(cb.getValue()));
            }
        }
        Collections.sort(allUsedBoxes, new Comparator<CheckBoxModel<Dependency>>() {
            public int compare(CheckBoxModel<Dependency> o1, CheckBoxModel<Dependency> o2) {
                return useCounts.get(o2) - useCounts.get(o1);
            }
        });

        howMany = Math.min(allUsedBoxes.size(), howMany);
        List<CheckBoxModel<Dependency>> result = new ArrayList<CheckBoxModel<Dependency>>();
        for (int i = 0; i < howMany; i++) {
            result.add(allUsedBoxes.get(i));
        }
        return Collections.unmodifiableList(result);
    }

}