remove duplicated ListenableFuture and SettableFuture

src/main/java/com/b44t/messenger/util/concurrent/ListenableFuture.java

@@ -1,13 +0,0 @@
-package com.b44t.messenger.util.concurrent;
-
-import java.util.concurrent.ExecutionException;
-import java.util.concurrent.Future;
-
-public interface ListenableFuture<T> extends Future<T> {
-  void addListener(Listener<T> listener);
-
-  public interface Listener<T> {
-    public void onSuccess(T result);
-    public void onFailure(ExecutionException e);
-  }
-}

src/main/java/com/b44t/messenger/util/concurrent/SettableFuture.java

@@ -1,136 +0,0 @@
-package com.b44t.messenger.util.concurrent;
-
-import java.util.LinkedList;
-import java.util.List;
-import java.util.concurrent.ExecutionException;
-import java.util.concurrent.TimeUnit;
-import java.util.concurrent.TimeoutException;
-
-public class SettableFuture<T> implements ListenableFuture<T> {
-
-  private final List<Listener<T>> listeners = new LinkedList<>();
-
-  private          boolean   completed;
-  private          boolean   canceled;
-  private volatile T         result;
-  private volatile Throwable exception;
-
-  public SettableFuture() { }
-
-  public SettableFuture(T value) {
-    this.result    = value;
-    this.completed = true;
-  }
-
-  @Override
-  public synchronized boolean cancel(boolean mayInterruptIfRunning) {
-    if (!completed && !canceled) {
-      canceled = true;
-      return true;
-    }
-
-    return false;
-  }
-
-  @Override
-  public synchronized boolean isCancelled() {
-    return canceled;
-  }
-
-  @Override
-  public synchronized boolean isDone() {
-    return completed;
-  }
-
-  public boolean set(T result) {
-    synchronized (this) {
-      if (completed || canceled) return false;
-
-      this.result    = result;
-      this.completed = true;
-
-      notifyAll();
-    }
-
-    notifyAllListeners();
-    return true;
-  }
-
-  public boolean setException(Throwable throwable) {
-    synchronized (this) {
-      if (completed || canceled) return false;
-
-      this.exception = throwable;
-      this.completed = true;
-
-      notifyAll();
-    }
-
-    notifyAllListeners();
-    return true;
-  }
-
-  public void deferTo(ListenableFuture<T> other) {
-    other.addListener(new Listener<T>() {
-      @Override
-      public void onSuccess(T result) {
-        SettableFuture.this.set(result);
-      }
-
-      @Override
-      public void onFailure(ExecutionException e) {
-        SettableFuture.this.setException(e.getCause());
-      }
-    });
-  }
-
-  @Override
-  public synchronized T get() throws InterruptedException, ExecutionException {
-    while (!completed) wait();
-
-    if (exception != null) throw new ExecutionException(exception);
-    else                   return result;
-  }
-
-  @Override
-  public synchronized T get(long timeout, TimeUnit unit)
-      throws InterruptedException, ExecutionException, TimeoutException
-  {
-    long startTime = System.currentTimeMillis();
-
-    while (!completed && System.currentTimeMillis() - startTime > unit.toMillis(timeout)) {
-      wait(unit.toMillis(timeout));
-    }
-
-    if (!completed) throw new TimeoutException();
-    else            return get();
-  }
-
-  @Override
-  public void addListener(Listener<T> listener) {
-    synchronized (this) {
-      listeners.add(listener);
-
-      if (!completed) return;
-    }
-
-    notifyListener(listener);
-  }
-
-  private void notifyAllListeners() {
-    List<Listener<T>> localListeners;
-
-    synchronized (this) {
-      localListeners = new LinkedList<>(listeners);
-    }
-
-    for (Listener<T> listener : localListeners) {
-      notifyListener(listener);
-    }
-  }
-
-  private void notifyListener(Listener<T> listener) {
-    if (exception != null) listener.onFailure(new ExecutionException(exception));
-    else                   listener.onSuccess(result);
-  }
-}