Java tutorial
/*- * Copyright 2009 Diamond Light Source Ltd. * * This file is part of GDA. * * GDA is free software: you can redistribute it and/or modify it under the * terms of the GNU General Public License version 3 as published by the Free * Software Foundation. * * GDA 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 General Public License along * with GDA. If not, see <http://www.gnu.org/licenses/>. */ package gda.gui.beans; import gda.device.DeviceException; import gda.device.EnumPositioner; import gda.device.NamedEnumPositioner; import gda.factory.Findable; import gda.factory.Finder; import gda.observable.IObserver; import java.awt.event.ActionEvent; import java.awt.event.ActionListener; import javax.swing.BorderFactory; import javax.swing.ComboBoxModel; import javax.swing.DefaultComboBoxModel; import javax.swing.JComboBox; import javax.swing.JLabel; import javax.swing.SwingUtilities; import org.apache.commons.lang.ArrayUtils; import org.slf4j.Logger; import org.slf4j.LoggerFactory; public class EnumPositionerComboBean extends javax.swing.JPanel implements IObserver, Runnable { private static final Logger logger = LoggerFactory.getLogger(EnumPositionerComboBean.class); protected JComboBox cmbChoices; protected String label; protected String enumPositionerName = ""; protected String[] commandPositions = null; protected EnumPositioner enumPositioner = null; // lock to prevent a backlog of threads trying to update this Bean. protected volatile boolean updateLock = false; @Override public void setEnabled(boolean enabled) { super.setEnabled(enabled); cmbChoices.setEnabled(enabled); } /** * Constructor. */ public EnumPositionerComboBean() { super(); } private java.awt.Dimension initialPreferredSize = new java.awt.Dimension(150, 67); public java.awt.Dimension getInitialPreferredSize() { return initialPreferredSize; } public void setInitialPreferredSize(java.awt.Dimension initialPreferredSize) { this.initialPreferredSize = initialPreferredSize; } private String cmbLabel; public String getCmbLabel() { return cmbLabel; } public void setCmbLabel(String cmbLabel) { this.cmbLabel = cmbLabel; } private void initGUI() { if (initialPreferredSize != null) this.setPreferredSize(initialPreferredSize); if (label != null && !label.isEmpty()) this.setBorder(BorderFactory.createTitledBorder(label)); if (cmbLabel != null && !cmbLabel.isEmpty()) this.add(new JLabel(cmbLabel)); this.add(getCmbChoices()); } /** * Call this to connect to the object and build the UI. */ public void configure() { if (enumPositionerName != null) { try { Findable obj = Finder.getInstance().find(enumPositionerName); if (obj != null && obj instanceof EnumPositioner) { this.enumPositioner = (EnumPositioner) obj; enumPositioner.addIObserver(this); if (obj instanceof NamedEnumPositioner) { String[] positionNameList = ((NamedEnumPositioner) enumPositioner).getPositions(); commandPositions = positionNameList; } else { commandPositions = enumPositioner.getPositions(); } initGUI(); updateDisplay(); } } catch (DeviceException e) { logger.error("deviceexception while retrieving positions from positioner: " + e.getMessage()); } } else { logger.error("EnumPositionerComboBean cannot connect to object as information missing!"); } } /** * @see gda.observable.IObserver#update(java.lang.Object, java.lang.Object) */ @Override public void update(Object theObserved, Object changeCode) { updateDisplay(); } /** * @return the label */ public String getLabel() { return label; } /** * @param label * the label to set */ public void setLabel(String label) { this.label = label; } /** * @return the enumPositionerName */ public String getEnumPositionerName() { return enumPositionerName; } /** * @param enumPositionerName * the enumPositionerName to set */ public void setEnumPositionerName(String enumPositionerName) { this.enumPositionerName = enumPositionerName; } /** * Must be called after the positions array has been populated. * * @return JComboBox */ private JComboBox getCmbChoices() { if (cmbChoices == null && commandPositions != null) { ComboBoxModel cmbChoicesModel = new DefaultComboBoxModel(commandPositions); cmbChoices = new JComboBox(); cmbChoices.setModel(cmbChoicesModel); cmbChoices.addActionListener(new ActionListener() { @Override public void actionPerformed(ActionEvent evt) { uk.ac.gda.util.ThreadManager.getThread(new Runnable() { @Override public void run() { cmbChoicesActionPerformed(); } }).start(); } }); } return cmbChoices; } protected void cmbChoicesActionPerformed() { // if the change was not caused by an update if (!updateLock) { try { enumPositioner.moveTo(cmbChoices.getSelectedItem()); } catch (DeviceException e) { logger.error("device exception while trying to move " + enumPositionerName + " to " + (String) cmbChoices.getSelectedItem() + ": " + e.getMessage()); } } } private void updateDisplay() { if (!updateLock) { updateLock = true; SwingUtilities.invokeLater(this); } } /** * {@inheritDoc} Updates the displayed information. This MUST only be called from the Swing Thread via the * updateDisplay method. * * @see java.lang.Runnable#run() */ @Override public void run() { synchronized (this) { try { String currentPosition = (String) enumPositioner.getPosition(); if (enumPositioner instanceof NamedEnumPositioner) { currentPosition = ((NamedEnumPositioner) enumPositioner).getPositionName(); } int location = ArrayUtils.indexOf(commandPositions, currentPosition); //MXGDA-1057 do not select the position again if it's already at the correct position if (cmbChoices.getSelectedIndex() != location) { cmbChoices.setSelectedIndex(location); } } catch (DeviceException e) { logger.error("Exception while trying to observe " + enumPositionerName + ": " + e.getMessage()); } finally { updateLock = false; } } } }