Java tutorial
/******************************************************************************* * Copyright (c) 2010 Stephan Muehlstrasser 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: * Stephan Muehlstrasser - Initial implementation based on * org.eclipse.jdt.internal.ui.preferences.OverlayPreferenceStore *******************************************************************************/ package ccw.preferences; import org.eclipse.core.runtime.Assert; import org.eclipse.jface.preference.IPreferenceStore; import org.eclipse.jface.preference.PreferenceStore; import org.eclipse.jface.util.IPropertyChangeListener; import org.eclipse.jface.util.PropertyChangeEvent; /** * An overlaying preference store. */ public class OverlayPreferenceStore implements IPreferenceStore { public static final class TypeDescriptor { private TypeDescriptor() { } } public static final TypeDescriptor BOOLEAN = new TypeDescriptor(); public static final TypeDescriptor DOUBLE = new TypeDescriptor(); public static final TypeDescriptor FLOAT = new TypeDescriptor(); public static final TypeDescriptor INT = new TypeDescriptor(); public static final TypeDescriptor LONG = new TypeDescriptor(); public static final TypeDescriptor STRING = new TypeDescriptor(); public static class OverlayKey { TypeDescriptor fDescriptor; String fKey; public OverlayKey(TypeDescriptor descriptor, String key) { fDescriptor = descriptor; fKey = key; } } private class PropertyListener implements IPropertyChangeListener { /* * @see IPropertyChangeListener#propertyChange(PropertyChangeEvent) */ public void propertyChange(PropertyChangeEvent event) { OverlayKey key = findOverlayKey(event.getProperty()); if (key != null) propagateProperty(fParent, key, fStore); } } private IPreferenceStore fParent; private IPreferenceStore fStore; private OverlayKey[] fOverlayKeys; private PropertyListener fPropertyListener; private boolean fLoaded; public OverlayPreferenceStore(IPreferenceStore parent, OverlayKey[] overlayKeys) { fParent = parent; fOverlayKeys = overlayKeys; fStore = new PreferenceStore(); } private OverlayKey findOverlayKey(String key) { for (int i = 0; i < fOverlayKeys.length; i++) { if (fOverlayKeys[i].fKey.equals(key)) return fOverlayKeys[i]; } return null; } private boolean covers(String key) { return (findOverlayKey(key) != null); } private void propagateProperty(IPreferenceStore orgin, OverlayKey key, IPreferenceStore target) { if (orgin.isDefault(key.fKey)) { if (!target.isDefault(key.fKey)) target.setToDefault(key.fKey); return; } TypeDescriptor d = key.fDescriptor; if (BOOLEAN == d) { boolean originValue = orgin.getBoolean(key.fKey); boolean targetValue = target.getBoolean(key.fKey); if (targetValue != originValue) target.setValue(key.fKey, originValue); } else if (DOUBLE == d) { double originValue = orgin.getDouble(key.fKey); double targetValue = target.getDouble(key.fKey); if (targetValue != originValue) target.setValue(key.fKey, originValue); } else if (FLOAT == d) { float originValue = orgin.getFloat(key.fKey); float targetValue = target.getFloat(key.fKey); if (targetValue != originValue) target.setValue(key.fKey, originValue); } else if (INT == d) { int originValue = orgin.getInt(key.fKey); int targetValue = target.getInt(key.fKey); if (targetValue != originValue) target.setValue(key.fKey, originValue); } else if (LONG == d) { long originValue = orgin.getLong(key.fKey); long targetValue = target.getLong(key.fKey); if (targetValue != originValue) target.setValue(key.fKey, originValue); } else if (STRING == d) { String originValue = orgin.getString(key.fKey); String targetValue = target.getString(key.fKey); if (targetValue != null && originValue != null && !targetValue.equals(originValue)) target.setValue(key.fKey, originValue); } } public void propagate() { for (int i = 0; i < fOverlayKeys.length; i++) propagateProperty(fStore, fOverlayKeys[i], fParent); } private void loadProperty(IPreferenceStore orgin, OverlayKey key, IPreferenceStore target, boolean forceInitialization) { TypeDescriptor d = key.fDescriptor; if (BOOLEAN == d) { if (forceInitialization) target.setValue(key.fKey, true); target.setValue(key.fKey, orgin.getBoolean(key.fKey)); target.setDefault(key.fKey, orgin.getDefaultBoolean(key.fKey)); } else if (DOUBLE == d) { if (forceInitialization) target.setValue(key.fKey, 1.0D); target.setValue(key.fKey, orgin.getDouble(key.fKey)); target.setDefault(key.fKey, orgin.getDefaultDouble(key.fKey)); } else if (FLOAT == d) { if (forceInitialization) target.setValue(key.fKey, 1.0F); target.setValue(key.fKey, orgin.getFloat(key.fKey)); target.setDefault(key.fKey, orgin.getDefaultFloat(key.fKey)); } else if (INT == d) { if (forceInitialization) target.setValue(key.fKey, 1); target.setValue(key.fKey, orgin.getInt(key.fKey)); target.setDefault(key.fKey, orgin.getDefaultInt(key.fKey)); } else if (LONG == d) { if (forceInitialization) target.setValue(key.fKey, 1L); target.setValue(key.fKey, orgin.getLong(key.fKey)); target.setDefault(key.fKey, orgin.getDefaultLong(key.fKey)); } else if (STRING == d) { if (forceInitialization) target.setValue(key.fKey, "1"); //$NON-NLS-1$ target.setValue(key.fKey, orgin.getString(key.fKey)); target.setDefault(key.fKey, orgin.getDefaultString(key.fKey)); } } public void load() { for (int i = 0; i < fOverlayKeys.length; i++) loadProperty(fParent, fOverlayKeys[i], fStore, true); fLoaded = true; } public void loadDefaults() { for (int i = 0; i < fOverlayKeys.length; i++) setToDefault(fOverlayKeys[i].fKey); } public void start() { if (fPropertyListener == null) { fPropertyListener = new PropertyListener(); fParent.addPropertyChangeListener(fPropertyListener); } } public void stop() { if (fPropertyListener != null) { fParent.removePropertyChangeListener(fPropertyListener); fPropertyListener = null; } } /* * @see IPreferenceStore#addPropertyChangeListener(IPropertyChangeListener) */ public void addPropertyChangeListener(IPropertyChangeListener listener) { fStore.addPropertyChangeListener(listener); } /* * @see IPreferenceStore#removePropertyChangeListener(IPropertyChangeListener) */ public void removePropertyChangeListener(IPropertyChangeListener listener) { fStore.removePropertyChangeListener(listener); } /* * @see IPreferenceStore#firePropertyChangeEvent(String, Object, Object) */ public void firePropertyChangeEvent(String name, Object oldValue, Object newValue) { fStore.firePropertyChangeEvent(name, oldValue, newValue); } /* * @see IPreferenceStore#contains(String) */ public boolean contains(String name) { return fStore.contains(name); } /* * @see IPreferenceStore#getBoolean(String) */ public boolean getBoolean(String name) { return fStore.getBoolean(name); } /* * @see IPreferenceStore#getDefaultBoolean(String) */ public boolean getDefaultBoolean(String name) { return fStore.getDefaultBoolean(name); } /* * @see IPreferenceStore#getDefaultDouble(String) */ public double getDefaultDouble(String name) { return fStore.getDefaultDouble(name); } /* * @see IPreferenceStore#getDefaultFloat(String) */ public float getDefaultFloat(String name) { return fStore.getDefaultFloat(name); } /* * @see IPreferenceStore#getDefaultInt(String) */ public int getDefaultInt(String name) { return fStore.getDefaultInt(name); } /* * @see IPreferenceStore#getDefaultLong(String) */ public long getDefaultLong(String name) { return fStore.getDefaultLong(name); } /* * @see IPreferenceStore#getDefaultString(String) */ public String getDefaultString(String name) { return fStore.getDefaultString(name); } /* * @see IPreferenceStore#getDouble(String) */ public double getDouble(String name) { return fStore.getDouble(name); } /* * @see IPreferenceStore#getFloat(String) */ public float getFloat(String name) { return fStore.getFloat(name); } /* * @see IPreferenceStore#getInt(String) */ public int getInt(String name) { return fStore.getInt(name); } /* * @see IPreferenceStore#getLong(String) */ public long getLong(String name) { return fStore.getLong(name); } /* * @see IPreferenceStore#getString(String) */ public String getString(String name) { return fStore.getString(name); } /* * @see IPreferenceStore#isDefault(String) */ public boolean isDefault(String name) { return fStore.isDefault(name); } /* * @see IPreferenceStore#needsSaving() */ public boolean needsSaving() { return fStore.needsSaving(); } /* * @see IPreferenceStore#putValue(String, String) */ public void putValue(String name, String value) { if (covers(name)) fStore.putValue(name, value); } /* * @see IPreferenceStore#setDefault(String, double) */ public void setDefault(String name, double value) { if (covers(name)) fStore.setDefault(name, value); } /* * @see IPreferenceStore#setDefault(String, float) */ public void setDefault(String name, float value) { if (covers(name)) fStore.setDefault(name, value); } /* * @see IPreferenceStore#setDefault(String, int) */ public void setDefault(String name, int value) { if (covers(name)) fStore.setDefault(name, value); } /* * @see IPreferenceStore#setDefault(String, long) */ public void setDefault(String name, long value) { if (covers(name)) fStore.setDefault(name, value); } /* * @see IPreferenceStore#setDefault(String, String) */ public void setDefault(String name, String value) { if (covers(name)) fStore.setDefault(name, value); } /* * @see IPreferenceStore#setDefault(String, boolean) */ public void setDefault(String name, boolean value) { if (covers(name)) fStore.setDefault(name, value); } /* * @see IPreferenceStore#setToDefault(String) */ public void setToDefault(String name) { fStore.setToDefault(name); } /* * @see IPreferenceStore#setValue(String, double) */ public void setValue(String name, double value) { if (covers(name)) fStore.setValue(name, value); } /* * @see IPreferenceStore#setValue(String, float) */ public void setValue(String name, float value) { if (covers(name)) fStore.setValue(name, value); } /* * @see IPreferenceStore#setValue(String, int) */ public void setValue(String name, int value) { if (covers(name)) fStore.setValue(name, value); } /* * @see IPreferenceStore#setValue(String, long) */ public void setValue(String name, long value) { if (covers(name)) fStore.setValue(name, value); } /* * @see IPreferenceStore#setValue(String, String) */ public void setValue(String name, String value) { if (covers(name)) fStore.setValue(name, value); } /* * @see IPreferenceStore#setValue(String, boolean) */ public void setValue(String name, boolean value) { if (covers(name)) fStore.setValue(name, value); } /** * The keys to add to the list of overlay keys. * <p> * Note: This method must be called before {@link #load()} is called. * </p> * * @param keys * @since 3.0 */ public void addKeys(OverlayKey[] keys) { Assert.isTrue(!fLoaded); Assert.isNotNull(keys); int overlayKeysLength = fOverlayKeys.length; OverlayKey[] result = new OverlayKey[keys.length + overlayKeysLength]; for (int i = 0, length = overlayKeysLength; i < length; i++) result[i] = fOverlayKeys[i]; for (int i = 0, length = keys.length; i < length; i++) result[overlayKeysLength + i] = keys[i]; fOverlayKeys = result; if (fLoaded) load(); } }