A few basic Swing observables

rxjava-contrib/rxjava-swing/src/main/java/rx/SwingObservable.java

@@ -0,0 +1,108 @@
+/**
+ * Copyright 2013 Netflix, Inc.
+ * 
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ * 
+ * http://www.apache.org/licenses/LICENSE-2.0
+ * 
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+package rx;
+
+import static rx.Observable.filter;
+
+import java.awt.event.ActionEvent;
+import java.awt.event.KeyEvent;
+import java.awt.event.MouseEvent;
+import java.util.Set;
+
+import javax.swing.AbstractButton;
+import javax.swing.JComponent;
+
+import rx.swing.sources.AbstractButtonSource;
+import rx.swing.sources.KeyEventSource;
+import rx.swing.sources.MouseEventSource;
+import rx.util.functions.Func1;
+
+/**
+ * Allows creating observables from various sources specific to Swing. 
+ */
+public enum SwingObservable { ; // no instances
+
+    /**
+     * Creates an observable corresponding to a Swing button action.
+     * 
+     * @param button 
+     *            The button to register the observable for.
+     * @return Observable of action events.
+     */
+    public static Observable<ActionEvent> fromButtonAction(AbstractButton button) {
+        return AbstractButtonSource.fromActionOf(button);
+    }
+
+    /**
+     * Creates an observable corresponding to raw key events.
+     * 
+     * @param component
+     *            The component to register the observable for.
+     * @return Observable of key events.
+     */
+    public static Observable<KeyEvent> fromKeyEvents(JComponent component) {
+        return KeyEventSource.fromKeyEventsOf(component);
+    }
+
+    /**
+     * Creates an observable corresponding to raw key events, restricted a set of given key codes.
+     * 
+     * @param component
+     *            The component to register the observable for.
+     * @return Observable of key events.
+     */
+    public static Observable<KeyEvent> fromKeyEvents(JComponent component, final Set<Integer> keyCodes) {
+        return filter(fromKeyEvents(component), new Func1<KeyEvent, Boolean>() {
+            @Override
+            public Boolean call(KeyEvent event) {
+                return keyCodes.contains(event.getKeyCode());
+            }
+        });
+    }
+
+    /**
+     * Creates an observable that emits the set of all currently pressed keys each time
+     * this set changes. 
+     * @param component
+     *            The component to register the observable for.
+     * @return Observable of currently pressed keys.
+     */
+    public static Observable<Set<Integer>> currentlyPressedKeys(JComponent component) {
+        return KeyEventSource.currentlyPressedKeysOf(component);
+    }
+
+    /**
+     * Creates an observable corresponding to raw mouse events (excluding mouse motion events).
+     * 
+     * @param component
+     *            The component to register the observable for.
+     * @return Observable of mouse events.
+     */
+    public static Observable<MouseEvent> fromMouseEvents(JComponent component) {
+        return MouseEventSource.fromMouseEventsOf(component);
+    }
+
+    /**
+     * Creates an observable corresponding to raw mouse motion events.
+     * 
+     * @param component
+     *            The component to register the observable for.
+     * @return Observable of mouse motion events.
+     */
+    public static Observable<MouseEvent> fromMouseMotionEvents(JComponent component) {
+        return MouseEventSource.fromMouseMotionEventsOf(component);
+    }
+}

rxjava-contrib/rxjava-swing/src/main/java/rx/swing/sources/AbstractButtonSource.java

@@ -0,0 +1,101 @@
+/**
+ * Copyright 2013 Netflix, Inc.
+ * 
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ * 
+ * http://www.apache.org/licenses/LICENSE-2.0
+ * 
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+package rx.swing.sources;
+
+import static org.mockito.Mockito.mock;
+import static org.mockito.Mockito.never;
+import static org.mockito.Mockito.times;
+import static org.mockito.Mockito.verify;
+
+import java.awt.event.ActionEvent;
+import java.awt.event.ActionListener;
+
+import javax.swing.AbstractButton;
+
+import org.junit.Test;
+import org.mockito.Matchers;
+
+import rx.Observable;
+import rx.Observer;
+import rx.Subscription;
+import rx.subscriptions.Subscriptions;
+import rx.util.functions.Action0;
+import rx.util.functions.Action1;
+import rx.util.functions.Func1;
+
+public enum AbstractButtonSource { ; // no instances
+
+    public static Observable<ActionEvent> fromActionOf(final AbstractButton button) {
+        return Observable.create(new Func1<Observer<ActionEvent>, Subscription>() {
+            @Override
+            public Subscription call(final Observer<ActionEvent> observer) {
+                final ActionListener listener = new ActionListener() {
+                    @Override
+                    public void actionPerformed(ActionEvent e) {
+                        observer.onNext(e);
+                    }
+                };
+                button.addActionListener(listener);
+
+                return Subscriptions.create(new Action0() {
+                    @Override
+                    public void call() {
+                        button.removeActionListener(listener);
+                    }
+                });
+            }
+        });
+    }
+
+    public static class UnitTest {
+        @Test
+        public void testObservingActionEvents() {
+            @SuppressWarnings("unchecked")
+            Action1<ActionEvent> action = mock(Action1.class);
+            @SuppressWarnings("unchecked")
+            Action1<Exception> error = mock(Action1.class);
+            Action0 complete = mock(Action0.class);
+
+            final ActionEvent event = new ActionEvent(this, 1, "command");
+
+            @SuppressWarnings("serial")
+            class TestButton extends AbstractButton {
+                void testAction() {
+                    fireActionPerformed(event);
+                }
+            }
+
+            TestButton button = new TestButton();
+            Subscription sub = fromActionOf(button).subscribe(action, error, complete);
+
+            verify(action, never()).call(Matchers.<ActionEvent>any());
+            verify(error, never()).call(Matchers.<Exception>any());
+            verify(complete, never()).call();
+
+            button.testAction();
+            verify(action, times(1)).call(Matchers.<ActionEvent>any());
+
+            button.testAction();
+            verify(action, times(2)).call(Matchers.<ActionEvent>any());
+
+            sub.unsubscribe();
+            button.testAction();
+            verify(action, times(2)).call(Matchers.<ActionEvent>any());
+            verify(error, never()).call(Matchers.<Exception>any());
+            verify(complete, never()).call();
+        }
+    }
+}

rxjava-contrib/rxjava-swing/src/main/java/rx/swing/sources/KeyEventSource.java

@@ -0,0 +1,180 @@
+/**
+ * Copyright 2013 Netflix, Inc.
+ * 
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ * 
+ * http://www.apache.org/licenses/LICENSE-2.0
+ * 
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+package rx.swing.sources;
+
+import static java.util.Arrays.asList;
+import static org.mockito.Mockito.*;
+
+import java.awt.event.KeyEvent;
+import java.awt.event.KeyListener;
+import java.util.Collections;
+import java.util.HashSet;
+import java.util.Set;
+
+import javax.swing.JComponent;
+import javax.swing.JPanel;
+
+import org.junit.Test;
+import org.mockito.InOrder;
+import org.mockito.Matchers;
+
+import rx.Observable;
+import rx.Observer;
+import rx.Subscription;
+import rx.subscriptions.Subscriptions;
+import rx.util.functions.Action0;
+import rx.util.functions.Action1;
+import rx.util.functions.Func1;
+import rx.util.functions.Func2;
+
+public enum KeyEventSource { ; // no instances
+
+    public static Observable<KeyEvent> fromKeyEventsOf(final JComponent component) {
+        return Observable.create(new Func1<Observer<KeyEvent>, Subscription>() {
+            @Override
+            public Subscription call(final Observer<KeyEvent> observer) {
+                final KeyListener listener = new KeyListener() {
+                    @Override
+                    public void keyPressed(KeyEvent event) {
+                        observer.onNext(event);
+                    }
+
+                    @Override
+                    public void keyReleased(KeyEvent event) {
+                        observer.onNext(event);
+                    }
+
+                    @Override
+                    public void keyTyped(KeyEvent event) {
+                        observer.onNext(event);
+                    }
+                };
+                component.addKeyListener(listener);
+
+                return Subscriptions.create(new Action0() {
+                    @Override
+                    public void call() {
+                        component.removeKeyListener(listener);
+                    }
+                });
+            }
+        });
+    }
+
+    public static Observable<Set<Integer>> currentlyPressedKeysOf(JComponent component) {
+        return Observable.<KeyEvent, Set<Integer>>scan(fromKeyEventsOf(component), new HashSet<Integer>(), new Func2<Set<Integer>, KeyEvent, Set<Integer>>() {
+            @Override
+            public Set<Integer> call(Set<Integer> pressedKeys, KeyEvent event) {
+                Set<Integer> afterEvent = new HashSet<Integer>(pressedKeys);
+                switch (event.getID()) {
+                    case KeyEvent.KEY_PRESSED:
+                        afterEvent.add(event.getKeyCode());
+                        break;
+
+                    case KeyEvent.KEY_RELEASED:
+                        afterEvent.remove(event.getKeyCode());
+                        break;
+
+                    default: // nothing to do
+                }
+                return afterEvent;
+            }
+        });
+    }
+
+    public static class UnitTest {
+        private JComponent comp = new JPanel();
+
+        @Test
+        public void testObservingKeyEvents() {
+            @SuppressWarnings("unchecked")
+            Action1<KeyEvent> action = mock(Action1.class);
+            @SuppressWarnings("unchecked")
+            Action1<Exception> error = mock(Action1.class);
+            Action0 complete = mock(Action0.class);
+
+            final KeyEvent event = mock(KeyEvent.class);
+
+            Subscription sub = fromKeyEventsOf(comp).subscribe(action, error, complete);
+
+            verify(action, never()).call(Matchers.<KeyEvent>any());
+            verify(error, never()).call(Matchers.<Exception>any());
+            verify(complete, never()).call();
+
+            fireKeyEvent(event);
+            verify(action, times(1)).call(Matchers.<KeyEvent>any());
+
+            fireKeyEvent(event);
+            verify(action, times(2)).call(Matchers.<KeyEvent>any());
+
+            sub.unsubscribe();
+            fireKeyEvent(event);
+            verify(action, times(2)).call(Matchers.<KeyEvent>any());
+            verify(error, never()).call(Matchers.<Exception>any());
+            verify(complete, never()).call();
+        }
+
+        @Test
+        public void testObservingPressedKeys() {
+            @SuppressWarnings("unchecked")
+            Action1<Set<Integer>> action = mock(Action1.class);
+            @SuppressWarnings("unchecked")
+            Action1<Exception> error = mock(Action1.class);
+            Action0 complete = mock(Action0.class);
+
+            Subscription sub = currentlyPressedKeysOf(comp).subscribe(action, error, complete);
+
+            InOrder inOrder = inOrder(action);
+            inOrder.verify(action, times(1)).call(Collections.<Integer>emptySet());
+            verify(error, never()).call(Matchers.<Exception>any());
+            verify(complete, never()).call();
+
+            fireKeyEvent(keyEvent(1, KeyEvent.KEY_PRESSED));
+            inOrder.verify(action, times(1)).call(new HashSet<Integer>(asList(1)));
+            verify(error, never()).call(Matchers.<Exception>any());
+            verify(complete, never()).call();
+
+            fireKeyEvent(keyEvent(2, KeyEvent.KEY_PRESSED));
+            inOrder.verify(action, times(1)).call(new HashSet<Integer>(asList(1, 2)));
+
+            fireKeyEvent(keyEvent(2, KeyEvent.KEY_RELEASED));
+            inOrder.verify(action, times(1)).call(new HashSet<Integer>(asList(1)));
+
+            fireKeyEvent(keyEvent(3, KeyEvent.KEY_RELEASED));
+            inOrder.verify(action, times(1)).call(new HashSet<Integer>(asList(1)));
+
+            fireKeyEvent(keyEvent(1, KeyEvent.KEY_RELEASED));
+            inOrder.verify(action, times(1)).call(Collections.<Integer>emptySet());
+
+            sub.unsubscribe();
+
+            fireKeyEvent(keyEvent(1, KeyEvent.KEY_PRESSED));
+            inOrder.verify(action, never()).call(Matchers.<Set<Integer>>any());
+            verify(error, never()).call(Matchers.<Exception>any());
+            verify(complete, never()).call();
+        }
+
+        private KeyEvent keyEvent(int keyCode, int id) {
+            return new KeyEvent(comp, id, -1L, 0, keyCode, ' ');
+        }
+
+        private void fireKeyEvent(KeyEvent event) {
+            for (KeyListener listener: comp.getKeyListeners()) {
+                listener.keyTyped(event);
+            }
+        }
+    }
+}