de.anbos.eclipse.logviewer.plugin.ui.EncodingComboEditor.java Source code

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Here is the source code for de.anbos.eclipse.logviewer.plugin.ui.EncodingComboEditor.java

Source

package de.anbos.eclipse.logviewer.plugin.ui;

import java.lang.reflect.Method;
import java.nio.charset.Charset;
import java.util.Iterator;
import java.util.Set;
import java.util.SortedMap;

import org.eclipse.jface.preference.FieldEditor;
import org.eclipse.swt.SWT;
import org.eclipse.swt.graphics.GC;
import org.eclipse.swt.graphics.Point;
import org.eclipse.swt.layout.GridData;
import org.eclipse.swt.widgets.Combo;
import org.eclipse.swt.widgets.Composite;

import de.anbos.eclipse.logviewer.plugin.LogViewerPlugin;
import de.anbos.eclipse.logviewer.plugin.Logger;

/*
 * Copyright (c) 2007 - 2011 by Michael Mimo Moratti
 * 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.
 */

public class EncodingComboEditor extends FieldEditor {

    // Constant ----------------------------------------------------------------

    /**
     * Text limit constant (value <code>-1</code>) indicating unlimited
     * text limit and width.
     */
    public static int UNLIMITED = -1;

    // Attribute ---------------------------------------------------------------

    private Logger logger;
    private Combo combo;

    /**
     * Width of text field in characters; initially unlimited.
     */
    private int widthInChars = UNLIMITED;

    // Constructor -------------------------------------------------------------

    public EncodingComboEditor(String name, String labelText, int width, Composite parent) {
        logger = LogViewerPlugin.getDefault().getLogger();
        init(name, labelText);
        widthInChars = width;
        createControl(parent);
    }

    public EncodingComboEditor(String name, String labelText, Composite parent) {
        this(name, labelText, UNLIMITED, parent);
    }

    // Protected ---------------------------------------------------------------

    /* (non-Javadoc)
     * @see org.eclipse.jface.preference.FieldEditor#adjustForNumColumns(int)
     */
    protected void adjustForNumColumns(int numColumns) {
        GridData gd = (GridData) combo.getLayoutData();
        gd.horizontalSpan = numColumns - 1;
        // We only grab excess space if we have to
        // If another field editor has more columns then
        // we assume it is setting the width.
        gd.grabExcessHorizontalSpace = gd.horizontalSpan == 1;
    }

    /* (non-Javadoc)
     * @see org.eclipse.jface.preference.FieldEditor#doFillIntoGrid(org.eclipse.swt.widgets.Composite, int)
     */
    protected void doFillIntoGrid(Composite parent, int numColumns) {
        getLabelControl(parent);

        combo = getComboControl(parent);
        GridData gd = new GridData();
        gd.horizontalSpan = numColumns - 1;
        if (widthInChars != UNLIMITED) {
            GC gc = new GC(combo);
            try {
                Point extent = gc.textExtent("X");//$NON-NLS-1$
                gd.widthHint = widthInChars * extent.x;
            } finally {
                gc.dispose();
            }
        } else {
            gd.horizontalAlignment = GridData.FILL;
            gd.grabExcessHorizontalSpace = true;
        }
        combo.setLayoutData(gd);
    }

    /* (non-Javadoc)
     * @see org.eclipse.jface.preference.FieldEditor#doLoad()
     */
    protected void doLoad() {
        if (combo != null) {
            // fill the encoding data
            SortedMap<?, ?> charsets = Charset.availableCharsets();
            Set<?> keys = charsets.keySet();
            // fill the combo with all available encoding types
            Iterator<?> keyIterator = keys.iterator();
            while (keyIterator.hasNext()) {
                Object obj = charsets.get(keyIterator.next());
                try {
                    Method method = obj.getClass().getMethod("displayName", new Class[] {}); //$NON-NLS-1$
                    String encoding = (String) method.invoke(obj, new Object[] {});
                    combo.add(encoding);
                } catch (Exception e) {
                    logger.logError("unable to load all available character encondings for this platform", e); //$NON-NLS-1$
                }
            }
        }
        combo.setText(getPreferenceStore().getString(getPreferenceName()));
    }

    /* (non-Javadoc)
     * @see org.eclipse.jface.preference.FieldEditor#doLoadDefault()
     */
    protected void doLoadDefault() {
        if (combo != null) {
            String value = getPreferenceStore().getDefaultString(getPreferenceName());
            combo.setText(value);
        }
    }

    /* (non-Javadoc)
     * @see org.eclipse.jface.preference.FieldEditor#doStore()
     */
    protected void doStore() {
        getPreferenceStore().setValue(getPreferenceName(), getComboControl().getText());
    }

    protected Combo getComboControl() {
        return combo;
    }

    protected Combo getComboControl(Composite parent) {
        if (combo != null) {
            return combo;
        }
        combo = new Combo(parent, SWT.RIGHT);
        combo.setFont(parent.getFont());
        return combo;
    }

    // Public ------------------------------------------------------------------

    /* (non-Javadoc)
     * @see org.eclipse.jface.preference.FieldEditor#getNumberOfControls()
     */
    public int getNumberOfControls() {
        return 2;
    }
}