X-Git-Url: https://git.pterodactylus.net/?a=blobdiff_plain;f=src%2Fnet%2Fpterodactylus%2Futil%2Fbeans%2FAbstractBean.java;h=7200324dfc9158c60a129f85a7a44054752b4add;hb=c63257e8cc0ba1a5aca9364b22171abe7279d479;hp=df6f78963726e2fcee12deb7c758fdd3d606e0b9;hpb=e8cc52293a249598d1b2b3ad952dc296357d20d7;p=jSite2.git diff --git a/src/net/pterodactylus/util/beans/AbstractBean.java b/src/net/pterodactylus/util/beans/AbstractBean.java index df6f789..7200324 100644 --- a/src/net/pterodactylus/util/beans/AbstractBean.java +++ b/src/net/pterodactylus/util/beans/AbstractBean.java @@ -27,9 +27,8 @@ import java.util.List; /** * Abstract bean super class that contains property change listener management. - * + * * @author David ‘Bombe’ Roden <bombe@freenetproject.org> - * @version $Id$ */ public abstract class AbstractBean { @@ -38,7 +37,7 @@ public abstract class AbstractBean { /** * Adds a property change listener. - * + * * @param propertyChangeListener * The property change listener to add */ @@ -48,7 +47,7 @@ public abstract class AbstractBean { /** * Removes a property change listener. - * + * * @param propertyChangeListener * The property change listener to remove */ @@ -58,7 +57,7 @@ public abstract class AbstractBean { /** * Notifies all listeners that a property has changed. - * + * * @param property * The name of the property * @param oldValue @@ -68,10 +67,46 @@ public abstract class AbstractBean { */ protected void firePropertyChange(String property, Object oldValue, Object newValue) { PropertyChangeEvent propertyChangeEvent = new PropertyChangeEvent(this, property, oldValue, newValue); - for (PropertyChangeListener propertyChangeListener: propertyChangeListeners) { + for (PropertyChangeListener propertyChangeListener : propertyChangeListeners) { propertyChangeListener.propertyChange(propertyChangeEvent); } } + /** + * Fires a property change event if the two values are not equal. + * + * @param propertyName + * The name of the property + * @param oldValue + * The old value of the property + * @param newValue + * The new value of the property + */ + protected void fireIfPropertyChanged(String propertyName, Object oldValue, Object newValue) { + if (!equal(oldValue, newValue)) { + firePropertyChange(propertyName, oldValue, newValue); + } + } + + // + // PRIVATE METHODS + // + + /** + * Compares the two objects and returns whether they are equal according to + * {@link Object#equals(Object)}. This method takes null + * into account as a valid value for an object. + * + * @param first + * The first object + * @param second + * The second object + * @return true if the two objects are equal, + * false otherwise + */ + private boolean equal(Object first, Object second) { + return ((first == null) && (second == null)) || ((first != null) && first.equals(second)) || ((second != null) && second.equals(first)); + } + }