Operations toMap (3) and toMultimap (4)

Author: akarnokd

language-adaptors/rxjava-groovy/src/test/groovy/rx/lang/groovy/ObservableTests.groovy

@@ -345,6 +345,143 @@ def class ObservableTests {
           assertEquals(6, count);
     }
 
+    @Test
+    public void testToMap1() {
+        Map actual = new HashMap();
+        
+        Observable.from("a", "bb", "ccc", "dddd")
+        .toMap({String s -> s.length()})
+        .toBlockingObservable()
+        .forEach({s -> actual.putAll(s); });
+        
+        Map expected = new HashMap();
+        expected.put(1, "a");
+        expected.put(2, "bb");
+        expected.put(3, "ccc");
+        expected.put(4, "dddd");
+        
+        assertEquals(expected, actual);
+    }
+
+    @Test
+    public void testToMap2() {
+        Map actual = new HashMap();
+        
+        Observable.from("a", "bb", "ccc", "dddd")
+        .toMap({String s -> s.length()}, {String s -> s + s})
+        .toBlockingObservable()
+        .forEach({s -> actual.putAll(s); });
+        
+        Map expected = new HashMap();
+        expected.put(1, "aa");
+        expected.put(2, "bbbb");
+        expected.put(3, "cccccc");
+        expected.put(4, "dddddddd");
+        
+        assertEquals(expected, actual);
+    }
+
+    @Test
+    public void testToMap3() {
+        Map actual = new HashMap();
+        
+        LinkedHashMap last3 = new LinkedHashMap() {
+            public boolean removeEldestEntry(Map.Entry e) {
+                return size() > 3;
+            }
+        };
+        
+        Observable.from("a", "bb", "ccc", "dddd")
+        .toMap({String s -> s.length()}, {String s -> s + s}, { last3 })
+        .toBlockingObservable()
+        .forEach({s -> actual.putAll(s); });
+        
+        Map expected = new HashMap();
+        expected.put(2, "bbbb");
+        expected.put(3, "cccccc");
+        expected.put(4, "dddddddd");
+        
+        assertEquals(expected, actual);
+    }
+    @Test
+    public void testToMultimap1() {
+        Map actual = new HashMap();
+        
+        Observable.from("a", "b", "cc", "dd")
+        .toMultimap({String s -> s.length()})
+        .toBlockingObservable()
+        .forEach({s -> actual.putAll(s); });
+        
+        Map expected = new HashMap();
+        
+        expected.put(1, Arrays.asList("a", "b"));
+        expected.put(2, Arrays.asList("cc", "dd"));
+        
+        assertEquals(expected, actual);
+    }
+
+    @Test
+    public void testToMultimap2() {
+        Map actual = new HashMap();
+        
+        Observable.from("a", "b", "cc", "dd")
+        .toMultimap({String s -> s.length()}, {String s -> s + s})
+        .toBlockingObservable()
+        .forEach({s -> actual.putAll(s); });
+        
+        Map expected = new HashMap();
+        
+        expected.put(1, Arrays.asList("aa", "bb"));
+        expected.put(2, Arrays.asList("cccc", "dddd"));
+        
+        assertEquals(expected, actual);
+    }
+
+    @Test
+    public void testToMultimap3() {
+        Map actual = new HashMap();
+        
+        LinkedHashMap last1 = new LinkedHashMap() {
+            public boolean removeEldestEntry(Map.Entry e) {
+                return size() > 1;
+            }
+        };
+        
+        Observable.from("a", "b", "cc", "dd")
+        .toMultimap({String s -> s.length()}, {String s -> s + s}, { last1 })
+        .toBlockingObservable()
+        .forEach({s -> actual.putAll(s); });
+        
+        Map expected = new HashMap();
+        
+        expected.put(2, Arrays.asList("cccc", "dddd"));
+        
+        assertEquals(expected, actual);
+    }
+
+    @Test
+    public void testToMultimap4() {
+        Map actual = new HashMap();
+        
+        LinkedHashMap last1 = new LinkedHashMap() {
+            public boolean removeEldestEntry(Map.Entry e) {
+                return size() > 2;
+            }
+        };
+        
+        Observable.from("a", "b", "cc", "dd", "eee", "eee")
+        .toMultimap({String s -> s.length()}, {String s -> s + s}, { last1 }, 
+            {i -> i == 2 ? new ArrayList() : new HashSet() })
+        .toBlockingObservable()
+        .forEach({s -> actual.putAll(s); });
+        
+        Map expected = new HashMap();
+        
+        expected.put(2, Arrays.asList("cccc", "dddd"));
+        expected.put(3, new HashSet(Arrays.asList("eeeeee")));
+        
+        assertEquals(expected, actual);
+    }
 
     def class AsyncObservable implements OnSubscribeFunc {
 

rxjava-core/src/main/java/rx/Observable.java

@@ -19,8 +19,10 @@
 
 import java.util.ArrayList;
 import java.util.Arrays;
+import java.util.Collection;
 import java.util.Comparator;
 import java.util.List;
+import java.util.Map;
 import java.util.concurrent.ConcurrentHashMap;
 import java.util.concurrent.Future;
 import java.util.concurrent.TimeUnit;
@@ -86,6 +88,8 @@
 import rx.operators.OperationTimeInterval;
 import rx.operators.OperationTimeout;
 import rx.operators.OperationTimestamp;
+import rx.operators.OperationToMap;
+import rx.operators.OperationToMultimap;
 import rx.operators.OperationToObservableFuture;
 import rx.operators.OperationToObservableIterable;
 import rx.operators.OperationToObservableList;
@@ -5861,4 +5865,127 @@ public static <R> Observable<R> when(Plan0<R> p1, Plan0<R> p2, Plan0<R> p3, Plan
     public static <R> Observable<R> when(Plan0<R> p1, Plan0<R> p2, Plan0<R> p3, Plan0<R> p4, Plan0<R> p5, Plan0<R> p6, Plan0<R> p7, Plan0<R> p8, Plan0<R> p9) {
         return create(OperationJoinPatterns.when(p1, p2, p3, p4, p5, p6, p7, p8, p9));
     }
+    
+    /**
+     * Return an Observable that emits a single HashMap containing all items
+     * emitted by the source Observable, mapped by the keys returned by the
+     * {@code keySelector} function.
+     * 
+     * If a source item maps to the same key, the HashMap will contain the latest
+     * of those items.
+     * 
+     * @param keySelector the function that extracts the key from the source items
+     *                    to be used as keys in the HashMap.
+     * @return an Observable that emits a single HashMap containing the mapped
+     *         values of the source Observable
+     * @see <a href='http://msdn.microsoft.com/en-us/library/hh229137(v=vs.103).aspx'>MSDN: Observable.ToDictionary</a>
+     */
+    public <K> Observable<Map<K, T>> toMap(Func1<? super T, ? extends K> keySelector) {
+        return create(OperationToMap.toMap(this, keySelector));
+    }
+    
+    /**
+     * Return an Observable that emits a single HashMap containing elements with
+     * key and value extracted from the values emitted by the source Observable.
+     * 
+     * If a source item maps to the same key, the HashMap will contain the latest
+     * of those items.
+     * 
+     * @param keySelector the function that extracts the key from the source items
+     *                    to be used as key in the HashMap
+     * @param valueSelector the function that extracts the value from the source items
+     *                      to be used as value in the HashMap
+     * @return an Observable that emits a single HashMap containing the mapped
+     *         values of the source Observable
+     * @see <a href='http://msdn.microsoft.com/en-us/library/hh212075(v=vs.103).aspx'>MSDN: Observable.ToDictionary</a>
+     */
+    public <K, V> Observable<Map<K, V>> toMap(Func1<? super T, ? extends K> keySelector, Func1<? super T, ? extends V> valueSelector) {
+        return create(OperationToMap.toMap(this, keySelector, valueSelector));
+    }
+    
+    /**
+     * Return an Observable that emits a single Map, returned by the mapFactory function,
+     * containing key and value extracted from the values emitted by the source Observable.
+     * 
+     * @param keySelector the function that extracts the key from the source items
+     *                    to be used as key in the Map
+     * @param valueSelector the function that extracts the value from the source items
+     *                      to be used as value in the Map
+     * @param mapFactory the function that returns an Map instance to be used
+     * @return an Observable that emits a single Map containing the mapped
+     *         values of the source Observable
+     */
+    public <K, V> Observable<Map<K, V>> toMap(Func1<? super T, ? extends K> keySelector, Func1<? super T, ? extends V> valueSelector, Func0<? extends Map<K, V>> mapFactory) {
+        return create(OperationToMap.toMap(this, keySelector, valueSelector, mapFactory));
+    }
+    
+    /**
+     * Return an Observable that emits a single HashMap containing an ArrayList of elements,
+     * emitted by the source Observable and keyed by the keySelector function.
+     * 
+     * @param keySelector the function that extracts the key from the source items
+     *                    to be used as key in the HashMap
+     * @return an Observable that emits a single HashMap containing an ArrayList of elements
+     *         mapped from the source Observable
+     * @see <a href='http://msdn.microsoft.com/en-us/library/hh212098(v=vs.103).aspx'>MSDN: Observable.ToLookup</a>
+     */
+    public <K> Observable<Map<K, Collection<T>>> toMultimap(Func1<? super T, ? extends K> keySelector) {
+        return create(OperationToMultimap.toMultimap(this, keySelector));
+    }
+    
+    /**
+     * Return an Observable that emits a single HashMap containing an ArrayList of values,
+     * extracted by the valueSelector function, emitted by the source Observable
+     * and keyed by the keySelector function.
+     * 
+     * @param keySelector the function that extracts the key from the source items
+     *                    to be used as key in the HashMap
+     * @param valueSelector the function that extracts the value from the source items
+     *                      to be used as value in the Map
+     * @return an Observable that emits a single HashMap containing an ArrayList of elements
+     *         mapped from the source Observable
+     * 
+     * @see <a href='http://msdn.microsoft.com/en-us/library/hh229101(v=vs.103).aspx'>MSDN: Observable.ToLookup</a>
+     */
+    public <K, V> Observable<Map<K, Collection<V>>> toMultimap(Func1<? super T, ? extends K> keySelector, Func1<? super T, ? extends V> valueSelector) {
+        return create(OperationToMultimap.toMultimap(this, keySelector, valueSelector));
+    }
+    
+    /**
+     * Return an Observable that emits a single Map, returned by the mapFactory function,
+     * containing an ArrayList of values, extracted by the valueSelector function,
+     * emitted by the source Observable and keyed by the 
+     * keySelector function.
+     * 
+     * @param keySelector the function that extracts the key from the source items
+     *                    to be used as key in the Map
+     * @param valueSelector the function that extracts the value from the source items
+     *                      to be used as value in the Map
+     * @param mapFactory the function that returns an Map instance to be used
+     * @return an Observable that emits a single Map containing the list of mapped values
+     *         of the source observable.
+     */
+    public <K, V> Observable<Map<K, Collection<V>>> toMultimap(Func1<? super T, ? extends K> keySelector, Func1<? super T, ? extends V> valueSelector, Func0<? extends Map<K, Collection<V>>> mapFactory) {
+        return create(OperationToMultimap.toMultimap(this, keySelector, valueSelector, mapFactory));
+    }
+
+    /**
+     * Return an Observable that emits a single Map, returned by the mapFactory function,
+     * containing a custom collection of values, extracted by the valueSelector function,
+     * emitted by the source Observable and keyed by the 
+     * keySelector function.
+     * 
+     * @param keySelector the function that extracts the key from the source items
+     *                    to be used as key in the Map
+     * @param valueSelector the function that extracts the value from the source items
+     *                      to be used as value in the Map
+     * @param mapFactory the function that returns an Map instance to be used
+     * @param collectionFactory the function that returns a Collection instance for 
+     *                          a particular key to be used in the Map
+     * @return an Observable that emits a single Map containing the collection of mapped values
+     *         of the source observable.
+     */
+    public <K, V> Observable<Map<K, Collection<V>>> toMultimap(Func1<? super T, ? extends K> keySelector, Func1<? super T, ? extends V> valueSelector, Func0<? extends Map<K, Collection<V>>> mapFactory, Func1<? super K, ? extends Collection<V>> collectionFactory) {
+        return create(OperationToMultimap.toMultimap(this, keySelector, valueSelector, mapFactory, collectionFactory));
+    } 
 }