Java tutorial
/* * Copyright (c) 2014, 2015, Oracle and/or its affiliates. All rights reserved. * * Redistribution and use in source and binary forms, with or without * modification, are permitted provided that the following conditions * are met: * * - Redistributions of source code must retain the above copyright * notice, this list of conditions and the following disclaimer. * * - Redistributions in binary form must reproduce the above copyright * notice, this list of conditions and the following disclaimer in the * documentation and/or other materials provided with the distribution. * * - Neither the name of Oracle or the names of its * contributors may be used to endorse or promote products derived * from this software without specific prior written permission. * * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS * IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, * THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR * PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT OWNER OR * CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, * EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, * PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR * PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF * LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING * NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF THIS * SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE. */ package sample.fa; import java.awt.BorderLayout; import java.awt.event.ActionEvent; import java.awt.event.WindowAdapter; import java.awt.event.WindowEvent; import java.io.ByteArrayOutputStream; import java.io.File; import java.io.IOException; import java.io.OutputStreamWriter; import java.io.Writer; import java.nio.file.Files; import java.util.Optional; import javax.script.ScriptEngine; import javax.script.ScriptEngineFactory; import javax.script.ScriptEngineManager; import javax.swing.Box; import javax.swing.DefaultComboBoxModel; import javax.swing.JButton; import javax.swing.JComboBox; import javax.swing.JFileChooser; import javax.swing.JFrame; import javax.swing.JLabel; import javax.swing.JList; import javax.swing.JOptionPane; import javax.swing.JSplitPane; import javax.swing.JTextArea; import javax.swing.SwingUtilities; /** * * @author dferrin */ public class ScriptRunnerApplication { private DefaultComboBoxModel<ScriptEngine> languagesModel; private JTextArea scriptContents; private JTextArea scriptResults; void createGUI() { Box buttonBox = Box.createHorizontalBox(); JButton loadButton = new JButton("Load"); loadButton.addActionListener(this::loadScript); buttonBox.add(loadButton); JButton saveButton = new JButton("Save"); saveButton.addActionListener(this::saveScript); buttonBox.add(saveButton); JButton executeButton = new JButton("Execute"); executeButton.addActionListener(this::executeScript); buttonBox.add(executeButton); languagesModel = new DefaultComboBoxModel(); ScriptEngineManager sem = new ScriptEngineManager(); for (ScriptEngineFactory sef : sem.getEngineFactories()) { languagesModel.addElement(sef.getScriptEngine()); } JComboBox<ScriptEngine> languagesCombo = new JComboBox<>(languagesModel); JLabel languageLabel = new JLabel(); languagesCombo.setRenderer((JList<? extends ScriptEngine> list, ScriptEngine se, int index, boolean isSelected, boolean cellHasFocus) -> { ScriptEngineFactory sef = se.getFactory(); languageLabel.setText(sef.getEngineName() + " - " + sef.getLanguageName() + " (*." + String.join(", *.", sef.getExtensions()) + ")"); return languageLabel; }); buttonBox.add(Box.createHorizontalGlue()); buttonBox.add(languagesCombo); scriptContents = new JTextArea(); scriptContents.setRows(8); scriptContents.setColumns(40); scriptResults = new JTextArea(); scriptResults.setEditable(false); scriptResults.setRows(8); scriptResults.setColumns(40); JSplitPane jsp = new JSplitPane(JSplitPane.VERTICAL_SPLIT, scriptContents, scriptResults); JFrame frame = new JFrame("Script Runner"); frame.add(buttonBox, BorderLayout.NORTH); frame.add(jsp, BorderLayout.CENTER); frame.pack(); frame.addWindowListener(new WindowAdapter() { @Override public void windowClosing(WindowEvent e) { System.exit(0); } }); frame.setVisible(true); } private void loadScript(ActionEvent ae) { JFileChooser jfc = new JFileChooser(); jfc.showOpenDialog(scriptContents); if (jfc.getSelectedFile() != null) { loadScript(jfc.getSelectedFile()); } } void loadScript(File f) { try { scriptContents.setText(String.join("\n", Files.readAllLines(f.toPath()))); String name = f.getName(); int lastDot = name.lastIndexOf('.'); if (lastDot >= 0) { String extension = name.substring(lastDot + 1); for (int i = 0; i < languagesModel.getSize(); i++) { ScriptEngine se = languagesModel.getElementAt(i); if (se.getFactory().getExtensions().indexOf(extension) >= 0) { languagesModel.setSelectedItem(se); break; } } } } catch (IOException ex) { JOptionPane.showMessageDialog(scriptContents, ex.getMessage(), "Error Loading Script", JOptionPane.ERROR_MESSAGE); } } private void saveScript(ActionEvent ae) { JFileChooser jfc = new JFileChooser(); jfc.showOpenDialog(scriptContents); File f = jfc.getSelectedFile(); if (f != null) { try { Files.write(f.toPath(), scriptContents.getText().getBytes()); } catch (IOException ex) { JOptionPane.showMessageDialog(scriptContents, ex.getMessage(), "Error Saving Script", JOptionPane.ERROR_MESSAGE); } } } private void executeScript(ActionEvent ae) { ScriptEngine se = (ScriptEngine) languagesModel.getSelectedItem(); try (ByteArrayOutputStream baos = new ByteArrayOutputStream(); Writer w = new OutputStreamWriter(baos);) { se.getContext().setWriter(w); Optional<Object> result = Optional.ofNullable(se.eval(scriptContents.getText())); scriptResults.setText(baos.toString() + "\n>>>>>>\n" + result.orElse("-null-").toString()); } catch (Exception e) { e.printStackTrace(System.out); scriptResults.setText(e.getClass().getName() + " - " + e.getMessage()); } } public static void main(String[] args) { SwingUtilities.invokeLater(() -> { ScriptRunnerApplication app = new ScriptRunnerApplication(); app.createGUI(); if (args.length > 0) { File f = new File(args[0]); if (f.isFile()) { app.loadScript(f); } } }); } }