org.ect.reo.prefs.ui.DoubleFieldEditor.java Source code

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Here is the source code for org.ect.reo.prefs.ui.DoubleFieldEditor.java

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/*******************************************************************************
 * <copyright>
 * This file is part of the Extensible Coordination Tools (ECT).
 * Copyright (c) 2013 ECT developers. 
 * 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
 * </copyright>
 *******************************************************************************/

package org.ect.reo.prefs.ui;

import java.text.ParseException;
import java.text.ParsePosition;

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

import com.ibm.icu.text.NumberFormat;

public class DoubleFieldEditor extends StringFieldEditor {

    private double minValidValue = 00.009;
    private double maxValidValue = 99.999;

    public DoubleFieldEditor(String pref, String label, Composite parent, double min, double max) {
        super(pref, label, parent);
        this.minValidValue = min;
        this.maxValidValue = max;
    }

    /* (non-Javadoc)
     * @see org.eclipse.jface.preference.StringFieldEditor#doCheckState()
     */
    protected boolean doCheckState() {

        Text text = getTextControl();
        if (text == null)
            return false;

        try {
            NumberFormat numberFormatter = NumberFormat.getInstance();
            ParsePosition parsePosition = new ParsePosition(0);
            Number parsedNumber = numberFormatter.parse(text.getText(), parsePosition);

            if (parsedNumber == null) {
                showErrorMessage();
                return false;
            }

            double number = forceDouble(parsedNumber).doubleValue();

            if (number >= minValidValue && number <= maxValidValue
                    && parsePosition.getIndex() == text.getText().length()) {
                clearErrorMessage();
                return true;
            } else {
                showErrorMessage();
                return false;
            }

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

        return false;
    }

    /* (non-Javadoc)
     * @see org.eclipse.jface.preference.StringFieldEditor#doLoadDefault()
     */
    protected void doLoadDefault() {
        Text text = getTextControl();
        if (text != null) {
            double value = getPreferenceStore().getDefaultDouble(getPreferenceName());
            NumberFormat numberFormatter = NumberFormat.getNumberInstance();
            text.setText(numberFormatter.format(value));
        }
        valueChanged();
    }

    /* (non-Javadoc)
     * Method declared on FieldEditor.
     */
    protected void doLoad() {
        Text text = getTextControl();
        if (text != null) {
            double value = getPreferenceStore().getDouble(getPreferenceName());
            NumberFormat numberFormatter = NumberFormat.getNumberInstance();
            text.setText(numberFormatter.format(value));
        }
    }

    protected void doStore() {
        NumberFormat numberFormatter = NumberFormat.getInstance();
        Double value;
        try {
            value = forceDouble(numberFormatter.parse(getTextControl().getText()));
            getPreferenceStore().setValue(getPreferenceName(), value.doubleValue());
        } catch (ParseException e) {
            showErrorMessage();
        }

    }

    /**
     * The NumberFormatter.parse() could return a Long or Double
     * We are storing all values related to the page setup as doubles
     * so we call this function when ever we are getting values from
     * the dialog.
     * @param number
     * @return
     */
    private Double forceDouble(Number number) {
        if (!(number instanceof Double))
            return new Double(number.doubleValue());
        return (Double) number;
    }

}