Java tutorial
/* * Copyright (c) 2004-2006 Marco Maccaferri 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: * Marco Maccaferri - initial API and implementation */ package org.eclipsetrader.news.internal.preferences; import java.io.File; import java.io.FileWriter; import java.util.ArrayList; import java.util.Arrays; import java.util.List; import javax.xml.bind.JAXBContext; import javax.xml.bind.JAXBElement; import javax.xml.bind.Marshaller; import javax.xml.bind.Unmarshaller; import javax.xml.bind.ValidationEvent; import javax.xml.bind.ValidationEventHandler; import javax.xml.namespace.QName; import javax.xml.transform.stream.StreamSource; import org.eclipse.core.runtime.IStatus; import org.eclipse.core.runtime.Status; import org.eclipse.jface.preference.IPreferenceStore; import org.eclipse.jface.preference.PreferencePage; import org.eclipse.jface.viewers.ArrayContentProvider; import org.eclipse.jface.viewers.CheckStateChangedEvent; import org.eclipse.jface.viewers.CheckboxTableViewer; import org.eclipse.jface.viewers.ICheckStateListener; import org.eclipse.jface.viewers.ISelectionChangedListener; import org.eclipse.jface.viewers.IStructuredSelection; import org.eclipse.jface.viewers.LabelProvider; import org.eclipse.jface.viewers.SelectionChangedEvent; import org.eclipse.jface.viewers.StructuredSelection; import org.eclipse.jface.viewers.ViewerSorter; import org.eclipse.jface.window.Window; import org.eclipse.swt.SWT; import org.eclipse.swt.events.SelectionAdapter; import org.eclipse.swt.events.SelectionEvent; import org.eclipse.swt.layout.GridData; import org.eclipse.swt.layout.GridLayout; import org.eclipse.swt.widgets.Button; import org.eclipse.swt.widgets.Composite; import org.eclipse.swt.widgets.Control; import org.eclipse.swt.widgets.Label; import org.eclipse.swt.widgets.Spinner; import org.eclipse.ui.IWorkbench; import org.eclipse.ui.IWorkbenchPreferencePage; import org.eclipsetrader.news.internal.Activator; import org.eclipsetrader.news.internal.connectors.FeedSource; import org.eclipsetrader.news.internal.connectors.RSSNewsProvider; public class RSSPreferencesPage extends PreferencePage implements IWorkbenchPreferencePage { private Spinner interval; private CheckboxTableViewer table; private Button editButton; private Button removeButton; private List<FeedSource> list = new ArrayList<FeedSource>(); /* (non-Javadoc) * @see org.eclipse.ui.IWorkbenchPreferencePage#init(org.eclipse.ui.IWorkbench) */ @Override public void init(IWorkbench workbench) { } /* (non-Javadoc) * @see org.eclipse.jface.preference.PreferencePage#createContents(org.eclipse.swt.widgets.Composite) */ @Override protected Control createContents(Composite parent) { Composite content = new Composite(parent, SWT.NONE); GridLayout gridLayout = new GridLayout(2, false); gridLayout.marginWidth = gridLayout.marginHeight = 0; content.setLayout(gridLayout); Composite group = new Composite(content, SWT.NONE); gridLayout = new GridLayout(); gridLayout.numColumns = 3; gridLayout.marginWidth = gridLayout.marginHeight = 0; group.setLayout(gridLayout); group.setLayoutData(new GridData(SWT.BEGINNING, SWT.BEGINNING, false, false, 2, 1)); Label label = new Label(group, SWT.NONE); label.setText(Messages.RSSPreferencesPage_AutoUpdate); interval = new Spinner(group, SWT.BORDER); interval.setMinimum(1); interval.setMaximum(9999); label = new Label(group, SWT.NONE); label.setText(Messages.RSSPreferencesPage_Minutes); label = new Label(group, SWT.NONE); label.setText(Messages.RSSPreferencesPage_Subscriptions); label.setLayoutData(new GridData(SWT.BEGINNING, SWT.BEGINNING, false, false, 2, 1)); createViewer(content); group = new Composite(content, SWT.NONE); gridLayout = new GridLayout(1, false); gridLayout.marginWidth = gridLayout.marginHeight = 0; group.setLayout(gridLayout); group.setLayoutData(new GridData(SWT.BEGINNING, SWT.BEGINNING, false, false)); Button button = new Button(group, SWT.PUSH); button.setText(Messages.RSSPreferencesPage_Add); button.setLayoutData(new GridData(80, SWT.DEFAULT)); button.addSelectionListener(new SelectionAdapter() { @Override public void widgetSelected(SelectionEvent e) { RSSFeedDialog dlg = new RSSFeedDialog(getShell()); if (dlg.open() == Window.OK) { FeedSource feedSource = dlg.getFeedSource(); feedSource.setEnabled(true); list.add(feedSource); table.refresh(); table.setChecked(feedSource, feedSource.isEnabled()); table.setSelection(new StructuredSelection(feedSource), true); } } }); editButton = new Button(group, SWT.PUSH); editButton.setText(Messages.RSSPreferencesPage_Edit); editButton.setEnabled(false); editButton.setLayoutData(new GridData(80, SWT.DEFAULT)); editButton.addSelectionListener(new SelectionAdapter() { @Override public void widgetSelected(SelectionEvent e) { IStructuredSelection selection = (IStructuredSelection) table.getSelection(); FeedSource feedSource = (FeedSource) selection.getFirstElement(); RSSFeedDialog dlg = new RSSFeedDialog(getShell()); dlg.setFeedSource(feedSource); if (dlg.open() == Window.OK) { table.refresh(); } } }); removeButton = new Button(group, SWT.PUSH); removeButton.setText(Messages.RSSPreferencesPage_Remove); removeButton.setEnabled(false); removeButton.setLayoutData(new GridData(80, SWT.DEFAULT)); removeButton.addSelectionListener(new SelectionAdapter() { @Override public void widgetSelected(SelectionEvent e) { IStructuredSelection selection = (IStructuredSelection) table.getSelection(); list.removeAll(selection.toList()); table.remove(selection.toArray()); } }); performDefaults(); return content; } protected void createViewer(Composite parent) { table = CheckboxTableViewer.newCheckList(parent, SWT.SINGLE | SWT.BORDER | SWT.FULL_SELECTION); table.getTable().setHeaderVisible(false); table.getTable().setLinesVisible(false); GridData gridData = new GridData(SWT.FILL, SWT.FILL, true, true); gridData.heightHint = table.getTable().getItemHeight() * 15 + table.getTable().getBorderWidth() * 2; table.getControl().setLayoutData(gridData); table.setContentProvider(new ArrayContentProvider()); table.setLabelProvider(new LabelProvider() { @Override public String getText(Object element) { return ((FeedSource) element).getName(); } }); table.setSorter(new ViewerSorter()); table.setInput(list); table.addSelectionChangedListener(new ISelectionChangedListener() { @Override public void selectionChanged(SelectionChangedEvent event) { editButton.setEnabled(((IStructuredSelection) table.getSelection()).size() == 1); removeButton.setEnabled(!table.getSelection().isEmpty()); } }); table.addCheckStateListener(new ICheckStateListener() { @Override public void checkStateChanged(CheckStateChangedEvent event) { ((FeedSource) event.getElement()).setEnabled(event.getChecked()); } }); } /* (non-Javadoc) * @see org.eclipse.jface.preference.PreferencePage#performOk() */ @Override public boolean performOk() { IPreferenceStore store = Activator.getDefault().getPreferenceStore(); store.setValue(Activator.PREFS_UPDATE_INTERVAL, interval.getSelection()); try { File file = Activator.getDefault().getStateLocation().append(RSSNewsProvider.HEADLINES_FILE).toFile(); if (file.exists()) { file.delete(); } JAXBContext jaxbContext = JAXBContext.newInstance(FeedSource[].class); Marshaller marshaller = jaxbContext.createMarshaller(); marshaller.setEventHandler(new ValidationEventHandler() { @Override public boolean handleEvent(ValidationEvent event) { Status status = new Status(IStatus.WARNING, Activator.PLUGIN_ID, 0, "Error validating XML: " + event.getMessage(), null); //$NON-NLS-1$ Activator.getDefault().getLog().log(status); return true; } }); marshaller.setProperty(Marshaller.JAXB_FORMATTED_OUTPUT, Boolean.TRUE); marshaller.setProperty(Marshaller.JAXB_ENCODING, System.getProperty("file.encoding")); //$NON-NLS-1$ JAXBElement<FeedSource[]> element = new JAXBElement<FeedSource[]>(new QName("list"), FeedSource[].class, list.toArray(new FeedSource[list.size()])); marshaller.marshal(element, new FileWriter(file)); } catch (Exception e) { Status status = new Status(IStatus.WARNING, Activator.PLUGIN_ID, 0, "Error saving RSS subscriptions", //$NON-NLS-1$ null); Activator.getDefault().getLog().log(status); } return super.performOk(); } /* (non-Javadoc) * @see org.eclipse.jface.preference.PreferencePage#performDefaults() */ @Override protected void performDefaults() { IPreferenceStore store = Activator.getDefault().getPreferenceStore(); interval.setSelection(store.getInt(Activator.PREFS_UPDATE_INTERVAL)); FeedSource[] sources = getSources(); list.clear(); list.addAll(Arrays.asList(sources)); table.refresh(); for (int i = 0; i < sources.length; i++) { table.setChecked(sources[i], sources[i].isEnabled()); } super.performDefaults(); } protected FeedSource[] getSources() { try { File file = Activator.getDefault().getStateLocation().append(RSSNewsProvider.HEADLINES_FILE).toFile(); if (file.exists()) { JAXBContext jaxbContext = JAXBContext.newInstance(FeedSource[].class); Unmarshaller unmarshaller = jaxbContext.createUnmarshaller(); unmarshaller.setEventHandler(new ValidationEventHandler() { @Override public boolean handleEvent(ValidationEvent event) { Status status = new Status(IStatus.WARNING, Activator.PLUGIN_ID, 0, "Error validating XML: " + event.getMessage(), null); //$NON-NLS-1$ Activator.getDefault().getLog().log(status); return true; } }); JAXBElement<FeedSource[]> element = unmarshaller.unmarshal(new StreamSource(file), FeedSource[].class); return element.getValue(); } } catch (Exception e) { Status status = new Status(IStatus.WARNING, Activator.PLUGIN_ID, 0, "Error reading RSS subscriptions", //$NON-NLS-1$ null); Activator.getDefault().getLog().log(status); } return new FeedSource[0]; } }