Add support for the method toMap().

Author: javadev

src/main/java/com/github/underscore/$.java

@@ -588,6 +588,22 @@ public static <E> E[] toArray(final Iterable<E> iterable) {
         return (E[]) newArrayList(iterable).toArray();
     }
 
+    public <E> E[] toArray() {
+        return toArray((Iterable<E>) iterable);
+    }
+
+    public static <K, V> Map<K, V> toMap(final Iterable<Map.Entry<K, V>> iterable) {
+        final Map<K, V> result = newLinkedHashMap();
+        for (Map.Entry<K, V> entry : iterable) {
+            result.put(entry.getKey(), entry.getValue());
+        }
+        return result;
+    }
+
+    public <K, V> Map<K, V> toMap() {
+        return toMap((Iterable<Map.Entry<K, V>>) iterable);
+    }
+
     public static int size(final Iterable<?> iterable) {
         int size;
         final Iterator<?> iterator = iterable.iterator();
@@ -1667,6 +1683,10 @@ public <F extends Comparable<? super F>> Chain<T> sortBy(final Function1<T, F> f
             return new Chain<T>($.sortBy(list, func));
         }
 
+        public <K, V> Chain<Map<K, V>> toMap() {
+            return new Chain<Map<K, V>>($.toMap((Iterable<Map.Entry<K, V>>) list));
+        }
+
         public <K, V extends Comparable<? super V>> Chain<Map<K, V>> sortBy(final K key) {
             return new Chain<Map<K, V>>($.sortBy((List<Map<K, V>>) list, key));
         }

src/test/java/com/github/underscore/ChainingTest.java

@@ -383,4 +383,11 @@ public Integer apply(Integer accum, Integer length) {
         assertEquals(34, sum);
     }
 
+    @Test
+    public void chainToMap() {
+        assertEquals("{name1=one, name2=two}", $.chain((new LinkedHashMap<String, String>() { {
+            put("name1", "one");
+            put("name2", "two");
+        } }).entrySet()).toMap().item().toString());
+    }
 }

src/test/java/com/github/underscore/CollectionsTest.java

@@ -933,6 +933,20 @@ public void sample() {
     public void toArray() {
         final Object[] result = $.<Integer>toArray(asList(1, 2, 3, 4));
         assertEquals("1", result[0].toString());
+        final Object[] resultObj = new $(asList(1, 2, 3, 4)).toArray();
+        assertEquals("1", resultObj[0].toString());
+    }
+
+    @Test
+    public void toMap() {
+        assertEquals("{name1=one, name2=two}", $.toMap((new LinkedHashMap<String, String>() { {
+            put("name1", "one");
+            put("name2", "two");
+        } }).entrySet()).toString());
+        assertEquals("{name1=one, name2=two}", new $((new LinkedHashMap<String, String>() { {
+            put("name1", "one");
+            put("name2", "two");
+        } }).entrySet()).toMap().toString());
     }
 
 /*

src/test/java/com/github/underscore/UnderscoreTest.java

@@ -224,15 +224,46 @@ public void optional() {
     @Test
     public void stackoverflow() {
         // http://stackoverflow.com/questions/109383/how-to-sort-a-mapkey-value-on-the-values-in-java?rq=1
-        assertEquals("[D=67.3, B=67.4, C=67.4, A=99.5]", $.sortBy((new LinkedHashMap<String, Double>() { {
+        assertEquals("{D=67.3, B=67.4, C=67.4, A=99.5}", $.chain((new LinkedHashMap<String, Double>() { {
             put("A", 99.5);
             put("B", 67.4);
             put("C", 67.4);
             put("D", 67.3);
-        } }).entrySet(), new Function1<Map.Entry<String, Double>, Double>() {
+        } }).entrySet()).sortBy(new Function1<Map.Entry<String, Double>, Double>() {
             public Double apply(Map.Entry<String, Double> item) {
                 return item.getValue();
             }
-        }).toString());
+        }).toMap().item().toString());
+    }
+
+    @Test
+    public void stackoverflow2() {
+        // http://stackoverflow.com/questions/12229577/java-hashmap-sorting-string-integer-how-to-sort-it?lq=1
+        assertEquals("{a=5, f=5, c=4, e=3, b=2, d=2}", $.chain((new HashMap<String, Integer>() { {
+            put("a", 5);
+            put("b", 2);
+            put("c", 4);
+            put("d", 2);
+            put("e", 3);
+            put("f", 5);
+        } }).entrySet()).sortBy(new Function1<Map.Entry<String, Integer>, Integer>() {
+            public Integer apply(Map.Entry<String, Integer> item) {
+                return -item.getValue();
+            }
+        }).toMap().item().toString());
+    }
+
+    @Test
+    public void stackoverflow3() {
+        // http://stackoverflow.com/questions/11647889/sorting-the-mapkey-value-in-descending-order-based-on-the-value?lq=1
+        assertEquals("{C=50, A=34, B=25}", $.chain((new HashMap<String, Integer>() { {
+            put("A", 34);
+            put("B", 25);
+            put("C", 50);
+        } }).entrySet()).sortBy(new Function1<Map.Entry<String, Integer>, Integer>() {
+            public Integer apply(Map.Entry<String, Integer> item) {
+                return -item.getValue();
+            }
+        }).toMap().item().toString());
     }
 }