import java.util.ListIterator;
import java.util.Observable;
import java.util.Spliterator;
+import java.util.concurrent.locks.ReentrantReadWriteLock;
import java.util.function.Consumer;
import java.util.function.Predicate;
import java.util.function.UnaryOperator;
public class ObservableList<T> extends Observable implements List<T> {
private List<T> list;
+ private ReentrantReadWriteLock lock = new ReentrantReadWriteLock();
public ObservableList(List<T> list) {
this.list = list;
}
notifyObservers(index);
}
public int size() {
- return list.size();
+ try (LockHolder lh = lockForReading()) {
+ return list.size();
+ }
}
public boolean isEmpty() {
- return list.isEmpty();
+ try (LockHolder lh = lockForReading()) {
+ return list.isEmpty();
+ }
}
public boolean contains(@Nullable Object o) {
- return list.contains(o);
+ try (LockHolder lh = lockForReading()) {
+ return list.contains(o);
+ }
}
@NonNull
public Iterator<T> iterator() {
- return list.iterator();
+ throw new RuntimeException("Iterators break encapsulation and ignore locking");
+// return list.iterator();
}
public Object[] toArray() {
- return list.toArray();
+ try (LockHolder lh = lockForReading()) {
+ return list.toArray();
+ }
}
public <T1> T1[] toArray(@Nullable T1[] a) {
- return list.toArray(a);
+ try (LockHolder lh = lockForReading()) {
+ return list.toArray(a);
+ }
}
public boolean add(T t) {
- boolean result = list.add(t);
- if (result) forceNotify();
- return result;
+ try (LockHolder lh = lockForWriting()) {
+ boolean result = list.add(t);
+ lh.downgrade();
+ if (result) forceNotify();
+ return result;
+ }
}
public boolean remove(@Nullable Object o) {
- boolean result = list.remove(o);
- if (result) forceNotify();
- return result;
+ try (LockHolder lh = lockForWriting()) {
+ boolean result = list.remove(o);
+ lh.downgrade();
+ if (result) forceNotify();
+ return result;
+ }
}
public T removeQuietly(int index) {
return list.remove(index);
}
public boolean containsAll(@NonNull Collection<?> c) {
- return list.containsAll(c);
+ try (LockHolder lh = lockForReading()) {
+ return list.containsAll(c);
+ }
}
public boolean addAll(@NonNull Collection<? extends T> c) {
- boolean result = list.addAll(c);
- if (result) forceNotify();
- return result;
+ try (LockHolder lh = lockForWriting()) {
+ boolean result = list.addAll(c);
+ lh.downgrade();
+ if (result) forceNotify();
+ return result;
+ }
}
public boolean addAll(int index, @NonNull Collection<? extends T> c) {
- boolean result = list.addAll(index, c);
- if (result) forceNotify();
- return result;
+ try (LockHolder lh = lockForWriting()) {
+ boolean result = list.addAll(index, c);
+ lh.downgrade();
+ if (result) forceNotify();
+ return result;
+ }
}
public boolean addAllQuietly(int index, Collection<? extends T> c) {
return list.addAll(index, c);
}
public boolean removeAll(@NonNull Collection<?> c) {
- boolean result = list.removeAll(c);
- if (result) forceNotify();
- return result;
+ try (LockHolder lh = lockForWriting()) {
+ boolean result = list.removeAll(c);
+ lh.downgrade();
+ if (result) forceNotify();
+ return result;
+ }
}
public boolean retainAll(@NonNull Collection<?> c) {
- boolean result = list.retainAll(c);
- if (result) forceNotify();
- return result;
+ try (LockHolder lh = lockForWriting()) {
+ boolean result = list.retainAll(c);
+ lh.downgrade();
+ if (result) forceNotify();
+ return result;
+ }
}
@RequiresApi(api = Build.VERSION_CODES.N)
public void replaceAll(@NonNull UnaryOperator<T> operator) {
- list.replaceAll(operator);
- forceNotify();
+ try (LockHolder lh = lockForWriting()) {
+ list.replaceAll(operator);
+ lh.downgrade();
+ forceNotify();
+ }
}
@RequiresApi(api = Build.VERSION_CODES.N)
public void sort(@Nullable Comparator<? super T> c) {
- list.sort(c);
- forceNotify();
+ try (LockHolder lh = lockForWriting()) {
+ lock.writeLock().lock();
+ list.sort(c);
+ lh.downgrade();
+ forceNotify();
+ }
}
public void clear() {
- boolean wasEmpty = list.isEmpty();
- list.clear();
- if (!wasEmpty) forceNotify();
+ try (LockHolder lh = lockForWriting()) {
+ boolean wasEmpty = list.isEmpty();
+ list.clear();
+ lh.downgrade();
+ if (!wasEmpty) forceNotify();
+ }
}
public T get(int index) {
- return list.get(index);
+ try (LockHolder lh = lockForReading()) {
+ return list.get(index);
+ }
}
public T set(int index, T element) {
- T result = list.set(index, element);
- forceNotify();
- return result;
+ try (LockHolder lh = lockForWriting()) {
+ T result = list.set(index, element);
+ lh.downgrade();
+ forceNotify();
+ return result;
+ }
}
public void add(int index, T element) {
- list.add(index, element);
- forceNotify();
+ try (LockHolder lh = lockForWriting()) {
+ list.add(index, element);
+ lh.downgrade();
+ forceNotify();
+ }
}
public T remove(int index) {
- T result = list.remove(index);
- forceNotify();
- return result;
+ try (LockHolder lh = lockForWriting()) {
+ T result = list.remove(index);
+ lh.downgrade();
+ forceNotify();
+ return result;
+ }
}
public int indexOf(@Nullable Object o) {
- return list.indexOf(o);
+ try (LockHolder lh = lockForReading()) {
+ return list.indexOf(o);
+ }
}
public int lastIndexOf(@Nullable Object o) {
- return list.lastIndexOf(o);
+ try (LockHolder lh = lockForReading()) {
+ return list.lastIndexOf(o);
+ }
}
public ListIterator<T> listIterator() {
+ if (!lock.isWriteLockedByCurrentThread()) throw new RuntimeException(
+ "Iterators break encapsulation and ignore locking. Write-lock first");
return list.listIterator();
}
public ListIterator<T> listIterator(int index) {
+ if (!lock.isWriteLockedByCurrentThread()) throw new RuntimeException(
+ "Iterators break encapsulation and ignore locking. Write-lock first");
return list.listIterator(index);
}
public List<T> subList(int fromIndex, int toIndex) {
- return list.subList(fromIndex, toIndex);
+ try (LockHolder lh = lockForReading()) {
+ return list.subList(fromIndex, toIndex);
+ }
}
@RequiresApi(api = Build.VERSION_CODES.N)
public Spliterator<T> spliterator() {
+ if (!lock.isWriteLockedByCurrentThread()) throw new RuntimeException(
+ "Iterators break encapsulation and ignore locking. Write-lock first");
return list.spliterator();
}
@RequiresApi(api = Build.VERSION_CODES.N)
public boolean removeIf(Predicate<? super T> filter) {
- boolean result = list.removeIf(filter);
- if (result) forceNotify();
- return result;
+ try (LockHolder lh = lockForWriting()) {
+ boolean result = list.removeIf(filter);
+ lh.downgrade();
+ if (result) forceNotify();
+ return result;
+ }
}
@RequiresApi(api = Build.VERSION_CODES.N)
public Stream<T> stream() {
+ if (!lock.isWriteLockedByCurrentThread()) throw new RuntimeException(
+ "Iterators break encapsulation and ignore locking. Write-lock first");
return list.stream();
}
@RequiresApi(api = Build.VERSION_CODES.N)
public Stream<T> parallelStream() {
+ if (!lock.isWriteLockedByCurrentThread()) throw new RuntimeException(
+ "Iterators break encapsulation and ignore locking. Write-lock first");
return list.parallelStream();
}
@RequiresApi(api = Build.VERSION_CODES.N)
public void forEach(Consumer<? super T> action) {
- list.forEach(action);
+ try (LockHolder lh = lockForReading()) {
+ list.forEach(action);
+ }
}
public List<T> getList() {
+ if (!lock.isWriteLockedByCurrentThread()) throw new RuntimeException(
+ "Direct list access breaks encapsulation and ignore locking. Write-lock first");
return list;
}
public void setList(List<T> aList) {
- list = aList;
- forceNotify();
+ try (LockHolder lh = lockForWriting()) {
+ list = aList;
+ lh.downgrade();
+ forceNotify();
+ }
}
public void triggerItemChangedNotification(T item) {
- int index = list.indexOf(item);
- if (index == -1) {
- Log.d("ObList", "??? not sending notifications for item not found in the list");
- return;
+ try (LockHolder lh = lockForReading()) {
+ int index = list.indexOf(item);
+ if (index == -1) {
+ Log.d("ObList", "??? not sending notifications for item not found in the list");
+ return;
+ }
+ Log.d("ObList", "Notifying item change observers");
+ triggerItemChangedNotification(index);
}
- Log.d("ObList", "Notifying item change observers");
- triggerItemChangedNotification(index);
}
public void triggerItemChangedNotification(int index) {
forceNotify(index);
}
+ public LockHolder lockForWriting() {
+ ReentrantReadWriteLock.WriteLock wLock = lock.writeLock();
+ wLock.lock();
+
+ ReentrantReadWriteLock.ReadLock rLock = lock.readLock();
+ rLock.lock();
+
+ return new LockHolder(rLock, wLock);
+ }
+ public LockHolder lockForReading() {
+ ReentrantReadWriteLock.ReadLock rLock = lock.readLock();
+ rLock.lock();
+ return new LockHolder(rLock);
+ }
}
\ No newline at end of file
projects / mobile-ledger.git / blobdiff