Java tutorial
/******************************************************************************* * Copyright (C) 2015 Thomas Wolf <thomas.wolf@paranor.ch> * * 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 *******************************************************************************/ package org.eclipse.egit.ui.internal.preferences; import java.text.DateFormat; import java.text.SimpleDateFormat; import java.util.Date; import java.util.LinkedHashMap; import java.util.Map; import java.util.TimeZone; import org.eclipse.egit.ui.Activator; import org.eclipse.egit.ui.UIPreferences; import org.eclipse.egit.ui.internal.SWTUtils; import org.eclipse.egit.ui.internal.UIText; import org.eclipse.jface.preference.ComboFieldEditor; import org.eclipse.jface.preference.FieldEditor; import org.eclipse.jface.preference.FieldEditorPreferencePage; import org.eclipse.jface.preference.IPreferenceStore; import org.eclipse.jface.preference.StringFieldEditor; import org.eclipse.jface.util.IPropertyChangeListener; import org.eclipse.jface.util.PropertyChangeEvent; import org.eclipse.jgit.lib.PersonIdent; import org.eclipse.jgit.util.GitDateFormatter; import org.eclipse.swt.SWT; import org.eclipse.swt.layout.GridData; import org.eclipse.swt.widgets.Composite; import org.eclipse.swt.widgets.Label; import org.eclipse.ui.IWorkbench; import org.eclipse.ui.IWorkbenchPreferencePage; /** Preferences concerning date formats in EGit. */ public class DateFormatPreferencePage extends FieldEditorPreferencePage implements IWorkbenchPreferencePage { private static final PersonIdent SAMPLE = new PersonIdent("", "", //$NON-NLS-1$ //$NON-NLS-2$ new Date(System.currentTimeMillis() - 24 * 3600 * 1000), getDifferentTimeZone()); private static final Map<GitDateFormatter.Format, FormatInfo> DATA = initializeData(); private ComboFieldEditor formatChooser; private StringFieldEditor dateFormat; private Label dateFormatPreview; private Label formatExplanation; private String lastCustomValue; /** Creates a new instance. */ public DateFormatPreferencePage() { super(GRID); initializeData(); setTitle(UIText.DateFormatPreferencePage_title); } @Override public void init(IWorkbench workbench) { // Nothing to do } @Override protected IPreferenceStore doGetPreferenceStore() { return Activator.getDefault().getPreferenceStore(); } @Override protected void createFieldEditors() { String[][] values = new String[DATA.size()][2]; int i = 0; for (Map.Entry<GitDateFormatter.Format, FormatInfo> entry : DATA.entrySet()) { values[i][0] = entry.getValue().name; values[i][1] = entry.getKey() == null ? UIPreferences.DATE_FORMAT_CUSTOM : entry.getKey().name(); i++; } final Composite pane = getFieldEditorParent(); formatChooser = new ComboFieldEditor(UIPreferences.DATE_FORMAT_CHOICE, UIText.DateFormatPreferencePage_formatChooser_label, values, pane); addField(formatChooser); dateFormat = new StringFieldEditor(UIPreferences.DATE_FORMAT, UIText.DateFormatPreferencePage_formatInput_label, StringFieldEditor.UNLIMITED, StringFieldEditor.VALIDATE_ON_KEY_STROKE, pane) { @Override protected boolean doCheckState() { // Validate the contents. If we're disabled, we're showing some // built-in format string, which we always consider as valid. if (!getTextControl(pane).isEnabled()) { return true; } try { updatePreview(new SimpleDateFormat(getStringValue().trim())); return true; } catch (IllegalArgumentException e) { dateFormatPreview.setText(""); //$NON-NLS-1$ return false; } } @Override protected void doLoad() { // Set explicitly below } @Override protected void doStore() { // Never store invalid values, or built-in values if (getTextControl(pane).isEnabled() && doCheckState()) { super.doStore(); } } @Override public void setStringValue(String value) { super.setStringValue(value); refreshValidState(); } }; dateFormat.setEmptyStringAllowed(false); dateFormat.setErrorMessage(UIText.DateFormatPreferencePage_invalidDateFormat_message); addField(dateFormat); // We know that the layout will have two columns Label dpLabel = SWTUtils.createLabel(pane, UIText.DateFormatPreferencePage_datePreview_label); dpLabel.setLayoutData(SWTUtils.createGridData(SWT.DEFAULT, SWT.DEFAULT, false, false)); dateFormatPreview = SWTUtils.createLabel(pane, null, 1); Label dummyLabel = SWTUtils.createLabel(pane, ""); //$NON-NLS-1$ dummyLabel.setLayoutData(SWTUtils.createGridData(SWT.DEFAULT, SWT.DEFAULT, false, false)); formatExplanation = new Label(pane, SWT.LEFT | SWT.WRAP); GridData layout = SWTUtils.createGridData(SWT.DEFAULT, SWT.DEFAULT, false, true); formatExplanation.setLayoutData(layout); // Setup based on initial values. We don't get any events by the editors // on initial load! lastCustomValue = getPreferenceStore().getString(UIPreferences.DATE_FORMAT); String initialValue = getPreferenceStore().getString(UIPreferences.DATE_FORMAT_CHOICE); updateFields(initialValue); } @Override protected void initialize() { super.initialize(); // When the chooser's selection changes, update the dateFormat & // enablement formatChooser.setPropertyChangeListener(new IPropertyChangeListener() { @Override public void propertyChange(PropertyChangeEvent event) { if (FieldEditor.VALUE.equals(event.getProperty())) { GitDateFormatter.Format format = fromString((String) event.getOldValue()); if (format == null) { lastCustomValue = dateFormat.getStringValue(); } updateFields((String) event.getNewValue()); } } }); } private void updateFields(String newSelection) { GitDateFormatter.Format format = fromString(newSelection); FormatInfo info = DATA.get(format); formatExplanation.setText(info.explanation); if (format == null) { dateFormat.getTextControl(getFieldEditorParent()).setEnabled(true); dateFormat.setStringValue(lastCustomValue); } else { dateFormat.getTextControl(getFieldEditorParent()).setEnabled(false); dateFormat.setStringValue(info.format); updatePreview(format); } } @Override protected void performDefaults() { super.performDefaults(); // We don't get property changed events when the default values are // restored... lastCustomValue = getPreferenceStore().getDefaultString(UIPreferences.DATE_FORMAT); updateFields(getPreferenceStore().getDefaultString(UIPreferences.DATE_FORMAT_CHOICE)); } private GitDateFormatter.Format fromString(String value) { try { return GitDateFormatter.Format.valueOf(value); } catch (IllegalArgumentException | NullPointerException e) { return null; } } private void updatePreview(SimpleDateFormat format) { dateFormatPreview.setText(format.format(SAMPLE.getWhen())); } private void updatePreview(GitDateFormatter.Format format) { dateFormatPreview.setText(new GitDateFormatter(format).formatDate(SAMPLE)); } private static Map<GitDateFormatter.Format, FormatInfo> initializeData() { Map<GitDateFormatter.Format, FormatInfo> d = new LinkedHashMap<>(); d.put(GitDateFormatter.Format.DEFAULT, new FormatInfo(UIText.DateFormatPreferencePage_choiceGitDefault_label, "EEE MMM dd HH:mm:ss yyyy Z", //$NON-NLS-1$ UIText.DateFormatPreferencePage_helpGitDefault_label)); d.put(GitDateFormatter.Format.LOCAL, new FormatInfo(UIText.DateFormatPreferencePage_choiceGitLocal_label, "EEE MMM dd HH:mm:ss yyyy", //$NON-NLS-1$ UIText.DateFormatPreferencePage_helpGitLocal_label)); d.put(GitDateFormatter.Format.RELATIVE, new FormatInfo(UIText.DateFormatPreferencePage_choiceGitRelative_label, UIText.DateFormatPreferencePage_gitRelative_format_text, UIText.DateFormatPreferencePage_helpGitRelative_label)); d.put(GitDateFormatter.Format.ISO, new FormatInfo(UIText.DateFormatPreferencePage_choiceGitIso_label, "yyyy-MM-dd HH:mm:ss Z", //$NON-NLS-1$ UIText.DateFormatPreferencePage_helpGitIso_label)); d.put(GitDateFormatter.Format.RFC, new FormatInfo(UIText.DateFormatPreferencePage_choiceGitRfc_label, "EEE, dd MMM yyyy HH:mm:ss Z", //$NON-NLS-1$ UIText.DateFormatPreferencePage_helpGitRfc_label)); d.put(GitDateFormatter.Format.SHORT, new FormatInfo(UIText.DateFormatPreferencePage_choiceGitShort_label, "yyyy-MM-dd", //$NON-NLS-1$ UIText.DateFormatPreferencePage_helpGitShort_label)); DateFormat systemFormat = DateFormat.getDateTimeInstance(DateFormat.DEFAULT, DateFormat.DEFAULT); String localeLocalFormat = (systemFormat instanceof SimpleDateFormat) ? ((SimpleDateFormat) systemFormat).toPattern() : UIText.DateFormatPreferencePage_gitLocaleLocal_format_text; String localeFormat = (systemFormat instanceof SimpleDateFormat) ? localeLocalFormat + " Z" //$NON-NLS-1$ : UIText.DateFormatPreferencePage_gitLocale_format_text; d.put(GitDateFormatter.Format.LOCALE, new FormatInfo(UIText.DateFormatPreferencePage_choiceGitLocale_label, localeFormat, UIText.DateFormatPreferencePage_helpGitLocale_label)); d.put(GitDateFormatter.Format.LOCALELOCAL, new FormatInfo(UIText.DateFormatPreferencePage_choiceGitLocaleLocal_label, localeLocalFormat, UIText.DateFormatPreferencePage_helpGitLocaleLocal_label)); d.put(null, new FormatInfo(UIText.DateFormatPreferencePage_choiceCustom_label, "", //$NON-NLS-1$ UIText.DateFormatPreferencePage_helpCustom_label)); return d; } private static TimeZone getDifferentTimeZone() { TimeZone localTimeZone = TimeZone.getDefault(); int offset = (localTimeZone.getRawOffset() / 3600 / 1000 - 6); // 6h to the West, full hour. Now get back to a sane range: if (offset < -12) { offset += 24; } String[] zoneIds = TimeZone.getAvailableIDs(offset * 3600 * 1000); if (zoneIds.length == 0) { // Huh? return localTimeZone; } return TimeZone.getTimeZone(zoneIds[0]); } private static final class FormatInfo { private final String name; private final String format; private final String explanation; public FormatInfo(String name, String dateFormat, String explanation) { this.name = name; this.format = dateFormat; this.explanation = explanation; } } }