gov.nasa.ensemble.common.ui.preferences.LongFieldEditor.java Source code

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Here is the source code for gov.nasa.ensemble.common.ui.preferences.LongFieldEditor.java

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/*******************************************************************************
 * Copyright 2014 United States Government as represented by the
 * Administrator of the National Aeronautics and Space Administration.
 * All Rights Reserved.
 * 
 * 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.
 ******************************************************************************/
package gov.nasa.ensemble.common.ui.preferences;

import org.eclipse.jface.preference.StringFieldEditor;
import org.eclipse.jface.resource.JFaceResources;
import org.eclipse.swt.widgets.Composite;
import org.eclipse.swt.widgets.Text;

/**
 * A field editor for a long type preference.
 */
public class LongFieldEditor extends StringFieldEditor {
    private long minValidValue = 0;

    private long maxValidValue = Long.MAX_VALUE;

    private static final int DEFAULT_TEXT_LIMIT = 10;

    /**
     * Creates a new long field editor 
     */
    protected LongFieldEditor() {
        // 
    }

    /**
     * Creates an long field editor.
     * 
     * @param name the name of the preference this field editor works on
     * @param labelText the label text of the field editor
     * @param parent the parent of the field editor's control
     */
    public LongFieldEditor(String name, String labelText, Composite parent) {
        this(name, labelText, parent, DEFAULT_TEXT_LIMIT);
    }

    /**
     * Creates an long field editor.
     * 
     * @param name the name of the preference this field editor works on
     * @param labelText the label text of the field editor
     * @param parent the parent of the field editor's control
     * @param textLimit the maximum number of characters in the text.
     */
    public LongFieldEditor(String name, String labelText, Composite parent, int textLimit) {
        init(name, labelText);
        setTextLimit(textLimit);
        setEmptyStringAllowed(false);
        setErrorMessage(JFaceResources.getString("LongFieldEditor.errorMessage"));//$NON-NLS-1$
        createControl(parent);
    }

    /**
     * Sets the range of valid values for this field.
     * 
     * @param min the minimum allowed value (inclusive)
     * @param max the maximum allowed value (inclusive)
     */
    public void setValidRange(long min, long max) {
        minValidValue = min;
        maxValidValue = max;
        setErrorMessage(JFaceResources.format("LongFieldEditor.errorMessageRange", //$NON-NLS-1$
                new Object[] { new Long(min), new Long(max) }));
    }

    /* (non-Javadoc)
     * Method declared on StringFieldEditor.
     * Checks whether the entered String is a valid long or not.
     */
    @Override
    protected boolean checkState() {

        Text text = getTextControl();

        if (text == null) {
            return false;
        }

        String numberString = text.getText();
        try {
            long number = Long.valueOf(numberString).longValue();
            if (number >= minValidValue && number <= maxValidValue) {
                clearErrorMessage();
                return true;
            }

            showErrorMessage();
            return false;

        } catch (NumberFormatException e1) {
            showErrorMessage();
        }

        return false;
    }

    /* (non-Javadoc)
     * Method declared on FieldEditor.
     */
    @Override
    protected void doLoad() {
        Text text = getTextControl();
        if (text != null) {
            long value = getPreferenceStore().getLong(getPreferenceName());
            text.setText("" + value);//$NON-NLS-1$
            oldValue = "" + value; //$NON-NLS-1$
        }

    }

    /* (non-Javadoc)
     * Method declared on FieldEditor.
     */
    @Override
    protected void doLoadDefault() {
        Text text = getTextControl();
        if (text != null) {
            long value = getPreferenceStore().getDefaultLong(getPreferenceName());
            text.setText("" + value);//$NON-NLS-1$
        }
        valueChanged();
    }

    /* (non-Javadoc)
     * Method declared on FieldEditor.
     */
    @Override
    protected void doStore() {
        Text text = getTextControl();
        if (text != null) {
            Long i = new Long(text.getText());
            getPreferenceStore().setValue(getPreferenceName(), i.longValue());
        }
    }

    /**
     * Returns this field editor's current value as an long.
     *
     * @return the value
     * @exception NumberFormatException if the <code>String</code> does not
     *   contain a parsable long
     */
    public long getLongValue() throws NumberFormatException {
        return new Long(getStringValue()).longValue();
    }
}