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-rw-r--r--main/src/cgeo/geocaching/utils/Subject.java76
1 files changed, 0 insertions, 76 deletions
diff --git a/main/src/cgeo/geocaching/utils/Subject.java b/main/src/cgeo/geocaching/utils/Subject.java
deleted file mode 100644
index b1754cc..0000000
--- a/main/src/cgeo/geocaching/utils/Subject.java
+++ /dev/null
@@ -1,76 +0,0 @@
-package cgeo.geocaching.utils;
-
-import java.util.LinkedHashSet;
-import java.util.Set;
-
-/**
- * Synchronized implementation of the {@link ISubject} interface.
- *
- * @param <T>
- * the kind of data to observe
- */
-public class Subject<T> implements ISubject<T> {
-
- /**
- * Collection of observers.
- */
- protected final Set<IObserver<? super T>> observers = new LinkedHashSet<IObserver<? super T>>();
-
- @Override
- public synchronized boolean addObserver(final IObserver<? super T> observer) {
- final boolean added = observers.add(observer);
- if (added && observers.size() == 1) {
- onFirstObserver();
- }
- return added;
- }
-
- @Override
- public synchronized boolean deleteObserver(final IObserver<? super T> observer) {
- final boolean removed = observers.remove(observer);
- if (removed && observers.isEmpty()) {
- onLastObserver();
- }
- return removed;
- }
-
- @Override
- public synchronized boolean notifyObservers(final T arg) {
- final boolean nonEmpty = !observers.isEmpty();
- for (final IObserver<? super T> observer : observers) {
- observer.update(arg);
- }
- return nonEmpty;
- }
-
- @Override
- public synchronized int sizeObservers() {
- return observers.size();
- }
-
- @Override
- public synchronized boolean clearObservers() {
- final boolean nonEmpty = !observers.isEmpty();
- for (final IObserver<? super T> observer : observers) {
- deleteObserver(observer);
- }
- return nonEmpty;
- }
-
- /**
- * Method called when the collection of observers goes from empty to non-empty.
- * <p/>
- * The default implementation does nothing and may be overwritten by child classes.
- */
- protected void onFirstObserver() {
- }
-
- /**
- * Method called when the collection of observers goes from non-empty to empty.
- * <p/>
- * The default implementation does nothing and may be overwritten by child classes.
- */
- protected void onLastObserver() {
- }
-
-}