Java tutorial
/***************************************************************************** * This file is part of Rinzo * * Author: Claudio Cancinos * WWW: https://sourceforge.net/projects/editorxml * Copyright (C): 2008, Claudio Cancinos * * This program is free software; you can redistribute it and/or * modify it under the terms of the GNU Lesser General Public License * as published by the Free Software Foundation; either version 2 * of the License, or (at your option) any later version. * * This program is distributed in the hope that it will be useful, * but WITHOUT ANY WARRANTY; without even the implied warranty of * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the * GNU General Public License for more details. * * You should have received a copy of the GNU Lesser General Public * License along with this program; If not, see <http://www.gnu.org/licenses/> ****************************************************************************/ package ar.com.tadp.xml.rinzo.core.views; import java.util.Arrays; import java.util.List; import org.eclipse.jface.action.Action; import org.eclipse.jface.action.IAction; import org.eclipse.jface.action.IToolBarManager; import org.eclipse.jface.resource.ImageDescriptor; import org.eclipse.jface.text.Document; import org.eclipse.jface.text.source.SourceViewer; import org.eclipse.swt.SWT; import org.eclipse.swt.events.KeyEvent; import org.eclipse.swt.events.KeyListener; import org.eclipse.swt.events.SelectionAdapter; import org.eclipse.swt.events.SelectionEvent; import org.eclipse.swt.events.SelectionListener; import org.eclipse.swt.layout.FillLayout; import org.eclipse.swt.layout.GridData; import org.eclipse.swt.layout.GridLayout; import org.eclipse.swt.widgets.Button; import org.eclipse.swt.widgets.Combo; import org.eclipse.swt.widgets.Composite; import org.eclipse.swt.widgets.Label; import org.eclipse.ui.IEditorPart; import org.eclipse.ui.IWorkbenchPage; import org.eclipse.ui.IWorkbenchWindow; import org.eclipse.ui.PlatformUI; import org.eclipse.ui.part.ViewPart; import ar.com.tadp.xml.rinzo.XMLEditorPlugin; import ar.com.tadp.xml.rinzo.core.PluginImages; import ar.com.tadp.xml.rinzo.core.RinzoXMLEditor; import ar.com.tadp.xml.rinzo.core.XMLEditorConfiguration; /** * View used to evaluate XPath expressions over the selected opened editor. * * @author ccancinos */ public class XPathView extends ViewPart { private static final String XPATH_VIEW_AUTO_EVALUATION = "XPathView.autoEvaluate"; private SourceViewer resultViewer; private Combo expressionsCombo; private Button evaluateButton; private IAction clearAllAction; private boolean autoEvaluation; private IAction autoEvaluateAction; private KeyListener autoEvaluationListener; private KeyListener enterEvaluationListener; private SelectionListener selectionListener; private XPathEvaluator xPathEvaluator = new XPathEvaluator(); public XPathView() { } public void createPartControl(Composite parent) { parent.setLayout(new GridLayout(1, false)); parent.setLayoutData(new GridData(GridData.FILL_BOTH)); Composite expresionComposite = new Composite(parent, SWT.NONE); expresionComposite.setLayout(new GridLayout(3, false)); expresionComposite.setLayoutData(new GridData(GridData.FILL_HORIZONTAL)); Composite expresionContainer = new Composite(expresionComposite, SWT.NONE); expresionContainer.setLayout(new GridLayout(3, false)); expresionContainer.setLayoutData(new GridData(GridData.FILL_HORIZONTAL)); Label label = new Label(expresionContainer, SWT.NONE); label.setText("Expression:"); this.expressionsCombo = new Combo(expresionContainer, SWT.DROP_DOWN | SWT.SINGLE | SWT.LEAD); this.expressionsCombo.setLayout(new GridLayout(1, false)); this.expressionsCombo.setLayoutData(new GridData(GridData.FILL_HORIZONTAL)); this.expressionsCombo.setFocus(); this.expressionsCombo.setVisibleItemCount(8); this.expressionsCombo.setToolTipText("Enter XPath for Source XML"); this.autoEvaluationListener = new AutoEvaluationKeyListener(); this.enterEvaluationListener = new EnterEvaluationKeyListener(); this.expressionsCombo.addKeyListener(this.enterEvaluationListener); this.selectionListener = new SelectionListenerImplementation(); this.evaluateButton = new Button(expresionComposite, SWT.PUSH); this.evaluateButton.setText("evaluate"); this.evaluateButton.addSelectionListener(new SelectionAdapter() { public void widgetSelected(SelectionEvent e) { super.widgetSelected(e); evaluateExpression(); } }); Composite resultComposite = new Composite(parent, SWT.NONE); resultComposite.setLayout(new FillLayout()); resultComposite.setLayoutData(new GridData(GridData.FILL_BOTH)); this.resultViewer = new SourceViewer(resultComposite, null, SWT.BORDER | SWT.V_SCROLL | SWT.H_SCROLL); this.resultViewer.setInput(this); this.resultViewer.configure(new XMLEditorConfiguration()); this.resultViewer.setDocument(new Document("")); this.clearAllAction = new Action("Clear All") { public void run() { resultViewer.getDocument().set(""); resultViewer.refresh(); expressionsCombo.removeAll(); } }; this.clearAllAction .setImageDescriptor(ImageDescriptor.createFromImage(PluginImages.get(PluginImages.IMG_CLEAR))); this.autoEvaluateAction = new Action("Auto Evaluate XPath", IAction.AS_CHECK_BOX) { public void run() { setAutoEvaluation(!autoEvaluation); } }; this.autoEvaluateAction.setImageDescriptor( ImageDescriptor.createFromImage(PluginImages.get(PluginImages.IMG_XPATH_AUTO_EVALUATE))); this.setAutoEvaluation( XMLEditorPlugin.getDefault().getPreferenceStore().getBoolean(XPATH_VIEW_AUTO_EVALUATION)); this.autoEvaluateAction.setChecked(this.autoEvaluation); IToolBarManager toolbarManager = getViewSite().getActionBars().getToolBarManager(); toolbarManager.add(this.autoEvaluateAction); toolbarManager.add(this.clearAllAction); } private void evaluateExpression() { try { String result = this.xPathEvaluator.evaluate(this.getExpression(), this.getEditorContent()); if (!this.resultViewer.getDocument().get().equals(result.toString()) && result.length() != 0) { this.saveHistory(); } this.showXPathResult(result.toString()); } catch (Exception e) { String localizedMessage = (e.getLocalizedMessage() != null) ? e.getLocalizedMessage() : e.getCause().getLocalizedMessage(); this.showXPathResult(localizedMessage); } } private void setAutoEvaluation(boolean autoEvaluation) { XMLEditorPlugin.getDefault().getPreferenceStore().setValue(XPATH_VIEW_AUTO_EVALUATION, autoEvaluation); this.autoEvaluation = autoEvaluation; this.evaluateButton.setEnabled(!this.autoEvaluation); if (this.autoEvaluation) { this.expressionsCombo.addKeyListener(this.autoEvaluationListener); this.expressionsCombo.addSelectionListener(this.selectionListener); } else { this.expressionsCombo.removeKeyListener(this.autoEvaluationListener); this.expressionsCombo.removeSelectionListener(this.selectionListener); } } public void setFocus() { this.expressionsCombo.setFocus(); } private String getEditorContent() { return this.getActiveEditor().getSourceViewerEditor().getDocument().get(); } private String getExpression() { return this.expressionsCombo.getText(); } private void showXPathResult(String result) { this.resultViewer.getDocument().set(result); this.resultViewer.refresh(); } private void saveHistory() { List<String> history = Arrays.asList(this.expressionsCombo.getItems()); if (!history.contains(this.getExpression())) { this.expressionsCombo.add(this.getExpression(), 0); } } private RinzoXMLEditor getActiveEditor() { IWorkbenchWindow window = PlatformUI.getWorkbench().getActiveWorkbenchWindow(); if (window != null) { IWorkbenchPage page = window.getActivePage(); if (page != null) { IEditorPart editor = page.getActiveEditor(); if (editor instanceof RinzoXMLEditor) { return (RinzoXMLEditor) editor; } } } return null; } private final class SelectionListenerImplementation implements SelectionListener { public void widgetSelected(SelectionEvent e) { evaluateExpression(); } public void widgetDefaultSelected(SelectionEvent e) { evaluateExpression(); } } private final class AutoEvaluationKeyListener implements KeyListener { public void keyReleased(KeyEvent e) { evaluateExpression(); } public void keyPressed(KeyEvent e) { } } private final class EnterEvaluationKeyListener implements KeyListener { public void keyReleased(KeyEvent event) { if (event.keyCode == SWT.CR) { evaluateExpression(); } } public void keyPressed(KeyEvent e) { } } }