org.eclipse.equinox.internal.p2.ui.viewers.IUComparator.java Source code

Introduction

Here is the source code for org.eclipse.equinox.internal.p2.ui.viewers.IUComparator.java

Source

/*******************************************************************************
 *  Copyright (c) 2000, 2010 IBM Corporation and others.
 *  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
 *  http://www.eclipse.org/legal/epl-v10.html
 * 
 *  Contributors:
 *     IBM Corporation - initial API and implementation
 *******************************************************************************/
package org.eclipse.equinox.internal.p2.ui.viewers;

import org.eclipse.equinox.internal.p2.ui.ProvUI;
import org.eclipse.equinox.p2.metadata.IInstallableUnit;
import org.eclipse.jface.viewers.Viewer;
import org.eclipse.jface.viewers.ViewerComparator;

public class IUComparator extends ViewerComparator {
    public static final int IU_NAME = 0;
    public static final int IU_ID = 1;
    private int key;
    private boolean showingId = false;

    public IUComparator(int sortKey) {
        this.key = sortKey;
        showingId = sortKey == IU_ID;
    }

    /**
     * Use the specified column config to determine
     * whether the id should be used in lieu of an empty name
     * when sorting.
     * 
     * @param columnConfig
     */
    public void useColumnConfig(IUColumnConfig[] columnConfig) {
        for (int i = 0; i < columnConfig.length; i++)
            if (columnConfig[i].getColumnType() == IUColumnConfig.COLUMN_ID) {
                showingId = true;
                break;
            }
    }

    public int compare(Viewer viewer, Object obj1, Object obj2) {
        IInstallableUnit iu1 = ProvUI.getAdapter(obj1, IInstallableUnit.class);
        IInstallableUnit iu2 = ProvUI.getAdapter(obj2, IInstallableUnit.class);
        if (iu1 == null || iu2 == null)
            // If these are not iu's use the super class comparator.
            return super.compare(viewer, obj1, obj2);

        String key1, key2;
        if (key == IU_NAME) {
            // Compare the iu names in the default locale.
            // If a name is not defined, we use blank if we know the id is shown in another
            // column.  If the id is not shown elsewhere, then we are displaying it, so use
            // the id instead.
            key1 = iu1.getProperty(IInstallableUnit.PROP_NAME, null);
            if (key1 == null)
                if (showingId)
                    key1 = ""; //$NON-NLS-1$
                else
                    key1 = iu1.getId();
            key2 = iu2.getProperty(IInstallableUnit.PROP_NAME, null);
            if (key2 == null)
                if (showingId)
                    key2 = ""; //$NON-NLS-1$
                else
                    key2 = iu2.getId();
        } else {
            key1 = iu1.getId();
            key2 = iu2.getId();
        }

        int result = 0;
        result = key1.compareToIgnoreCase(key2);
        if (result == 0) {
            // We want to show later versions first so compare backwards.
            result = iu2.getVersion().compareTo(iu1.getVersion());
        }
        return result;
    }
}