プログラマー向けJavaチートシート3. Javaのコレクション（標準、グアバ、Apache、Trove、GSコレクションなど）

• Collections.unmodifiableInterface-指定されたコレクションに基づいて変更不可能なコレクションを作成するためのラッパー。このコレクションを変更しようとするとUnsupportedOperationExceptionがスローされます
  
• Collections.synchronizedInterface-指定に基づいて同期コレクションを作成します。ベースコレクションへのアクセスがこの関数によって返されるコレクションラッパーを介している限り、スレッドセーフが保証されます。
  
• Collections.checkedInterface-型チェック付きのコレクションを動的に返します
  （実行時）、つまり、指定されたコレクションのタイプセーフビューを返します。
  間違った型の要素を追加しようとすると、ClassCastExceptionがスローされます。 使用する場合
  汎用JDKメカニズムは、コンパイルレベルで型のコンパイルをチェックしますが、このメカニズム
  バイパスすることができ、動的な型チェックではこの機会を利用できません。
  
  

• newSetFromMap（Map）-Setインターフェースの実装からMapインターフェースの実装を作成します。
• asLifoQueue（Deque）-Dequeからのビューを、Last In First Out（LIFO）の原理に基づいたキューとして返します。
  

• Arrays.asList-配列をリストとして表示できます
• emptySet、emptyList、およびemptyMap-空のセット、リスト、または空の未変更の実装を返します。
  地図
  
• singleton、singletonList、singletonMap -1つの指定されたオブジェクト（または1つのキーと値の関係）を含む変更不可能なセット、リスト、またはマップを返します
  
• nCopies-指定されたオブジェクトのn個のコピーを含む変更不可能なリストを返します

• AbstractCollection-セットでもリストでもないコレクション（「バッグ」やマルチセットなど）のCollectionインターフェイスの抽象実装。
  
• AbstractSet -Setインターフェイスの抽象的な実装。
• AbstractList-配列などのランダムアクセスを許可するリストのListインターフェイスの抽象的な実装。
  
• AbstractSequentialList-リンクリストなどのシーケンシャルアクセスベースのリスト用のListインターフェイスの抽象的な実装。
  
• AbstractQueue-抽象キューの実装。
• AbstractMap-抽象マップの実装。

• イテレータ -通常の列挙インターフェイスに似ていますが、優れた機能を備えています。
• Iterator -Enumerationインターフェイス機能に加えて、コレクションからアイテムを削除する機能が含まれます。
  
• ListIteratorはリストに使用されるイテレーターで、双方向の反復、要素の置換、要素の挿入、インデックスによる取得など、通常のイテレーターインターフェイスの機能を追加します。
  

• 比較可能 -それらを実装するクラスの自然なソート順を定義します。 この順序は、ソート方法で使用するか、ソートされたセットまたはマップを実装するために使用できます。
  
• Comparator-順序関係を表します。これは、ソートされたセットまたはマップ内のリストまたはメイン順序をソートするために使用できます。 型の自然な順序をオーバーライドしたり、Comparableインターフェイスを実装していない型のオブジェクトを順序付けたりできます。
  

• UnsupportedOperationException-このエラーは、コレクションが呼び出された操作をサポートしていない場合にスローされます。
  
• ConcurrentModificationException-イテレータまたはリストイテレータをスローします。イテレータが基づいているコレクションが（アルゴリズムの場合）反復中に予期せず変更された場合、メインリストが予期せず変更された場合はリストに基づいたビューもスローします
  

• RandomAccess-リストをマークするマーカーインターフェイスは、位置によって要素にすばやく（通常は一定時間）アクセスできるようにします。 これにより、シーケンシャルアクセスと位置アクセスの選択に関するこの動作を考慮したアルゴリズムを生成できます。

• 配列 -配列のハッシュをソート、検索、比較、サイズ変更、取得するための静的メソッドのセット。 また、配列を文字列に変換し、配列をプリミティブまたはオブジェクトで埋めるためのメソッドも含まれています。

<dependency> <groupId>com.google.guava</groupId> <artifactId>guava</artifactId> <version>18.0</version> </dependency> 

 dependencies { compile 'com.google.guava:guava:18.0' } 

 <dependency> <groupId>org.apache.commons</groupId> <artifactId>commons-collections4</artifactId> <version>4.0</version> </dependency> 

 'org.apache.commons:commons-collections4:4.0' 

 <dependency org="org.apache.commons" name="commons-collections4" rev="4.0"/> 

 <dependency> <groupId>net.sf.trove4j</groupId> <artifactId>trove4j</artifactId> <version>3.0.3</version> </dependency> 

 'net.sf.trove4j:trove4j:3.0.3' 

 <dependency org="net.sf.trove4j" name="trove4j" rev="3.0.3"/> 

 <dependency> <groupId>com.goldmansachs</groupId> <artifactId>gs-collections-api</artifactId> <version>6.2.0</version> </dependency> <dependency> <groupId>com.goldmansachs</groupId> <artifactId>gs-collections</artifactId> <version>6.2.0</version> </dependency> <dependency> <groupId>com.goldmansachs</groupId> <artifactId>gs-collections-testutils</artifactId> <version>6.2.0</version> <scope>test</scope> </dependency> <dependency> <groupId>com.goldmansachs</groupId> <artifactId>gs-collections-forkjoin</artifactId> <version>6.2.0</version> </dependency> 

 compile 'com.goldmansachs:gs-collections-api:6.2.0' compile 'com.goldmansachs:gs-collections:6.2.0' testCompile 'com.goldmansachs:gs-collections-testutils:6.2.0' compile 'com.goldmansachs:gs-collections-forkjoin:6.2.0' 

 <dependency org="com.goldmansachs" name="gs-collections-api" rev="6.2.0" /> <dependency org="com.goldmansachs" name="gs-collections" rev="6.2.0" /> <dependency org="com.goldmansachs" name="gs-collections-testutils" rev="6.2.0" /> <dependency org="com.goldmansachs" name="gs-collections-forkjoin" rev="6.2.0"/> 

  //     String INPUT_TEXT = "Hello World! Hello All! Hi World!"; //  Multiset Multiset<String> multiset = HashMultiset.create(Arrays.asList(INPUT_TEXT.split(" "))); //  -   System.out.println(multiset); //  [Hi, Hello x 2, World! x 2, All!] -    //     System.out.println(multiset.elementSet()); //  [Hi, Hello, World!, All!] -    //      System.out.println("Hello = " + multiset.count("Hello")); //  2 System.out.println("World = " + multiset.count("World!")); //  2 System.out.println("All = " + multiset.count("All!")); //  1 System.out.println("Hi = " + multiset.count("Hi")); //  1 System.out.println("Empty = " + multiset.count("Empty")); //  0 //        System.out.println(multiset.size()); // 6 //       System.out.println(multiset.elementSet().size()); // 4 

  //     String INPUT_TEXT = "Hello World! Hello All! Hi World!"; //  Multiset Multiset<String> multiset = TreeMultiset.create(Arrays.asList(INPUT_TEXT.split(" "))); //  -   System.out.println(multiset); //  [All!, Hello x 2, Hi, World! x 2]-    //     System.out.println(multiset.elementSet()); //  [All!, Hello, Hi, World!]-    //      System.out.println("Hello = " + multiset.count("Hello")); //  2 System.out.println("World = " + multiset.count("World!")); //  2 System.out.println("All = " + multiset.count("All!")); //  1 System.out.println("Hi = " + multiset.count("Hi")); //  1 System.out.println("Empty = " + multiset.count("Empty")); //  0 //        System.out.println(multiset.size()); // 6 //       System.out.println(multiset.elementSet().size()); // 4 

  //     String INPUT_TEXT = "Hello World! Hello All! Hi World!"; //  Multiset Multiset<String> multiset = LinkedHashMultiset.create(Arrays.asList(INPUT_TEXT.split(" "))); //  -   System.out.println(multiset); //  [Hello x 2, World! x 2, All!, Hi]-      //     System.out.println(multiset.elementSet()); //  [Hello, World!, All!, Hi] -      //      System.out.println("Hello = " + multiset.count("Hello")); //  2 System.out.println("World = " + multiset.count("World!")); //  2 System.out.println("All = " + multiset.count("All!")); //  1 System.out.println("Hi = " + multiset.count("Hi")); //  1 System.out.println("Empty = " + multiset.count("Empty")); //  0 //        System.out.println(multiset.size()); // 6 //       System.out.println(multiset.elementSet().size()); // 4 

  //     String INPUT_TEXT = "Hello World! Hello All! Hi World!"; //  Multiset Multiset<String> multiset = ConcurrentHashMultiset.create(Arrays.asList(INPUT_TEXT.split(" "))); //  -   System.out.println(multiset); //  [Hi, Hello x 2, World! x 2, All!] -    //     System.out.println(multiset.elementSet()); //  [Hi, Hello, World!, All!] -    //      System.out.println("Hello = " + multiset.count("Hello")); //  2 System.out.println("World = " + multiset.count("World!")); //  2 System.out.println("All = " + multiset.count("All!")); //  1 System.out.println("Hi = " + multiset.count("Hi")); //  1 System.out.println("Empty = " + multiset.count("Empty")); //  0 //        System.out.println(multiset.size()); // 6 //       System.out.println(multiset.elementSet().size()); // 4 

  //     String INPUT_TEXT = "Hello World! Hello All! Hi World!"; //  Multiset Bag bag = new HashBag(Arrays.asList(INPUT_TEXT.split(" "))); //  -   System.out.println(bag); //  [1:Hi,2:Hello,2:World!,1:All!] -    //     System.out.println(bag.uniqueSet()); //  [Hi, Hello, World!, All!] -    //      System.out.println("Hello = " + bag.getCount("Hello")); //  2 System.out.println("World = " + bag.getCount("World!")); //  2 System.out.println("All = " + bag.getCount("All!")); //  1 System.out.println("Hi = " + bag.getCount("Hi")); //  1 System.out.println("Empty = " + bag.getCount("Empty")); //  0 //        System.out.println(bag.size()); // 6 //       System.out.println(bag.uniqueSet().size()); // 4 

  //     String INPUT_TEXT = "Hello World! Hello All! Hi World!"; //  Multiset Bag bag = new TreeBag(Arrays.asList(INPUT_TEXT.split(" "))); //  -   System.out.println(bag); //  [1:All!,2:Hello,1:Hi,2:World!]-    //     System.out.println(bag.uniqueSet()); //  [All!, Hello, Hi, World!]-    //      System.out.println("Hello = " + bag.getCount("Hello")); //  2 System.out.println("World = " + bag.getCount("World!")); //  2 System.out.println("All = " + bag.getCount("All!")); //  1 System.out.println("Hi = " + bag.getCount("Hi")); //  1 System.out.println("Empty = " + bag.getCount("Empty")); //  0 //        System.out.println(bag.size()); // 6 //       System.out.println(bag.uniqueSet().size()); // 4 

  //     String INPUT_TEXT = "Hello World! Hello All! Hi World!"; //  Multiset Bag bag = SynchronizedBag.synchronizedBag(new HashBag(Arrays.asList(INPUT_TEXT.split(" ")))); //  -   System.out.println(bag); //  [1:Hi,2:Hello,2:World!,1:All!] -    //     System.out.println(bag.uniqueSet()); //  [Hi, Hello, World!, All!] -    //      System.out.println("Hello = " + bag.getCount("Hello")); //  2 System.out.println("World = " + bag.getCount("World!")); //  2 System.out.println("All = " + bag.getCount("All!")); //  1 System.out.println("Hi = " + bag.getCount("Hi")); //  1 System.out.println("Empty = " + bag.getCount("Empty")); //  0 //        System.out.println(bag.size()); // 6 //       System.out.println(bag.uniqueSet().size()); // 4 

  //     String INPUT_TEXT = "Hello World! Hello All! Hi World!"; //  Multiset Bag bag = SynchronizedSortedBag.synchronizedBag(new TreeBag(Arrays.asList(INPUT_TEXT.split(" ")))); //  -   System.out.println(bag); //  [1:All!,2:Hello,1:Hi,2:World!]-    //     System.out.println(bag.uniqueSet()); //  [All!, Hello, Hi, World!]-    //      System.out.println("Hello = " + bag.getCount("Hello")); //  2 System.out.println("World = " + bag.getCount("World!")); //  2 System.out.println("All = " + bag.getCount("All!")); //  1 System.out.println("Hi = " + bag.getCount("Hi")); //  1 System.out.println("Empty = " + bag.getCount("Empty")); //  0 //        System.out.println(bag.size()); //  6 //       System.out.println(bag.uniqueSet().size()); //  4 

  //     String INPUT_TEXT = "Hello World! Hello All! Hi World!"; //  Multiset MutableBag<String> bag = HashBag.newBag(Arrays.asList(INPUT_TEXT.split(" "))); //  -   System.out.println(bag); //  [Hi, World!, World!, Hello, Hello, All!]-    //     System.out.println(bag.toSet()); //  [Hi, Hello, World!, All!] -    //      System.out.println("Hello = " + bag.occurrencesOf("Hello")); //  2 System.out.println("World = " + bag.occurrencesOf("World!")); //  2 System.out.println("All = " + bag.occurrencesOf("All!")); //  1 System.out.println("Hi = " + bag.occurrencesOf("Hi")); //  1 System.out.println("Empty = " + bag.occurrencesOf("Empty")); //  0 //        System.out.println(bag.size()); // 6 //       System.out.println(bag.toSet().size()); // 4 

  //     String INPUT_TEXT = "Hello World! Hello All! Hi World!"; //  Multiset MutableSortedBag<String> bag = TreeBag.newBag(Arrays.asList(INPUT_TEXT.split(" "))); //  -   System.out.println(bag); //  [All!, Hello, Hello, Hi, World!, World!]-    //     System.out.println(bag.toSortedSet()); //  [All!, Hello, Hi, World!]-    //      System.out.println("Hello = " + bag.occurrencesOf("Hello")); //  2 System.out.println("World = " + bag.occurrencesOf("World!")); //  2 System.out.println("All = " + bag.occurrencesOf("All!")); //  1 System.out.println("Hi = " + bag.occurrencesOf("Hi")); //  1 System.out.println("Empty = " + bag.occurrencesOf("Empty")); //  0 //        System.out.println(bag.size()); // 6 //       System.out.println(bag.toSet().size()); // 4 

  //     String INPUT_TEXT = "Hello World! Hello All! Hi World!"; List<String> listResult = Arrays.asList(INPUT_TEXT.split(" ")); //   Multiset c  HashMap   Map<String, Integer> fakeMultiset = new HashMap<String,Integer>(listResult.size()); for(String word: listResult) { Integer cnt = fakeMultiset.get(word); fakeMultiset.put(word, cnt == null ? 1 : cnt + 1); } //  -   System.out.println(fakeMultiset); //  {World!=2, Hi=1, Hello=2, All!=1}-    //     System.out.println(fakeMultiset.keySet()); //  [World!, Hi, Hello, All!] -    //      System.out.println("Hello = " + fakeMultiset.get("Hello")); //  2 System.out.println("World = " + fakeMultiset.get("World!")); //  2 System.out.println("All = " + fakeMultiset.get("All!")); //  1 System.out.println("Hi = " + fakeMultiset.get("Hi")); //  1 System.out.println("Empty = " + fakeMultiset.get("Empty")); //  null //        Integer cnt = 0; for (Integer wordCount : fakeMultiset.values()){ cnt += wordCount; } System.out.println(cnt); // 6 //      System.out.println(fakeMultiset.size()); // 4 

  String INPUT_TEXT = "Hello World! Hello All! Hi World!"; //       List <String> words = Arrays.asList(INPUT_TEXT.split(" ")); //  Multimap Multimap<String, Integer> multiMap = HashMultimap.create(); //  Multimap int i = 0; for(String word: words) { multiMap.put(word, i); i++; } //       System.out.println(multiMap); //  {Hi=[4], Hello=[0, 2], World!=[1, 5], All!=[3]} -    //     System.out.println(multiMap.keySet()); //  [Hi, Hello, World!, All!] -    //        System.out.println("Hello = " + multiMap.get("Hello")); //  [0, 2] System.out.println("World = " + multiMap.get("World!")); //  [1, 5] System.out.println("All = " + multiMap.get("All!")); //  [3] System.out.println("Hi = " + multiMap.get("Hi")); //  [4] System.out.println("Empty = " + multiMap.get("Empty")); //  [] //        System.out.println(multiMap.size()); // 6 //       System.out.println(multiMap.keySet().size()); // 4 

  String INPUT_TEXT = "Hello World! Hello All! Hi World!"; //       List <String> words = Arrays.asList(INPUT_TEXT.split(" ")); //  Multimap Multimap<String, Integer> multiMap = ArrayListMultimap.create(); //  Multimap int i = 0; for(String word: words) { multiMap.put(word, i); i++; } //       System.out.println(multiMap); //  {Hi=[4], Hello=[0, 2], World!=[1, 5], All!=[3]} -    ,     //     System.out.println(multiMap.keySet()); //  [Hello, World!, All!, Hi]-    //        System.out.println("Hello = " + multiMap.get("Hello")); //  [0, 2] System.out.println("World = " + multiMap.get("World!")); //  [1, 5] System.out.println("All = " + multiMap.get("All!")); //  [3] System.out.println("Hi = " + multiMap.get("Hi")); //  [4] System.out.println("Empty = " + multiMap.get("Empty")); //  [] //        System.out.println(multiMap.size()); // 6 //       System.out.println(multiMap.keySet().size()); // 4 

  String INPUT_TEXT = "Hello World! Hello All! Hi World!"; //       List <String> words = Arrays.asList(INPUT_TEXT.split(" ")); //  Multimap Multimap<String, Integer> multiMap = LinkedHashMultimap.create(); //  Multimap int i = 0; for(String word: words) { multiMap.put(word, i); i++; } //       System.out.println(multiMap); //  {Hello=[0, 2], World!=[1, 5], All!=[3], Hi=[4]}-   //     System.out.println(multiMap.keySet()); //  [Hello, World!, All!, Hi]-    //        System.out.println("Hello = " + multiMap.get("Hello")); //  [0, 2] System.out.println("World = " + multiMap.get("World!")); //  [1, 5] System.out.println("All = " + multiMap.get("All!")); //  [3] System.out.println("Hi = " + multiMap.get("Hi")); //  [4] System.out.println("Empty = " + multiMap.get("Empty")); //  [] //        System.out.println(multiMap.size()); // 6 //       System.out.println(multiMap.keySet().size()); // 4 

  String INPUT_TEXT = "Hello World! Hello All! Hi World!"; //       List <String> words = Arrays.asList(INPUT_TEXT.split(" ")); //  Multimap Multimap<String, Integer> multiMap = LinkedListMultimap.create(); //  Multimap int i = 0; for(String word: words) { multiMap.put(word, i); i++; } //       System.out.println(multiMap); //  {Hello=[0, 2], World!=[1, 5], All!=[3], Hi=[4]}-   //     System.out.println(multiMap.keySet()); //  [Hello, World!, All!, Hi]-    //        System.out.println("Hello = " + multiMap.get("Hello")); //  [0, 2] System.out.println("World = " + multiMap.get("World!")); //  [1, 5] System.out.println("All = " + multiMap.get("All!")); //  [3] System.out.println("Hi = " + multiMap.get("Hi")); //  [4] System.out.println("Empty = " + multiMap.get("Empty")); //  [] //        System.out.println(multiMap.size()); // 6 //       System.out.println(multiMap.keySet().size()); // 4 

  String INPUT_TEXT = "Hello World! Hello All! Hi World!"; //       List<String> words = Arrays.asList(INPUT_TEXT.split(" ")); //  Multimap Multimap<String, Integer> multiMap = TreeMultimap.create(); //  Multimap int i = 0; for(String word: words) { multiMap.put(word, i); i++; } //       System.out.println(multiMap); //  {Hello=[0, 2], World!=[1, 5], All!=[3], Hi=[4]}-   //     System.out.println(multiMap.keySet()); //  [Hello, World!, All!, Hi]-    //        System.out.println("Hello = " + multiMap.get("Hello")); //  [0, 2] System.out.println("World = " + multiMap.get("World!")); //  [1, 5] System.out.println("All = " + multiMap.get("All!")); //  [3] System.out.println("Hi = " + multiMap.get("Hi")); //  [4] System.out.println("Empty = " + multiMap.get("Empty")); //  [] //        System.out.println(multiMap.size()); // 6 //       System.out.println(multiMap.keySet().size()); // 4 

  String INPUT_TEXT = "Hello World! Hello All! Hi World!"; //       List<String> words = Arrays.asList(INPUT_TEXT.split(" ")); //  Multimap MultiMap<String, Integer> multiMap = new MultiValueMap<String, Integer>(); //  Multimap int i = 0; for(String word: words) { multiMap.put(word, i); i++; } //       System.out.println(multiMap); //  {Hi=[4], Hello=[0, 2], World!=[1, 5], All!=[3]} -    //     System.out.println(multiMap.keySet()); //  [Hi, Hello, World!, All!] -    //        System.out.println("Hello = " + multiMap.get("Hello")); //  [0, 2] System.out.println("World = " + multiMap.get("World!")); //  [1, 5] System.out.println("All = " + multiMap.get("All!")); //  [3] System.out.println("Hi = " + multiMap.get("Hi")); //  [4] System.out.println("Empty = " + multiMap.get("Empty")); //  null //       System.out.println(multiMap.keySet().size()); // 4 

  String INPUT_TEXT = "Hello World! Hello All! Hi World!"; //       List<String> words = Arrays.asList(INPUT_TEXT.split(" ")); //  Multimap MultiMap<String, Integer> multiMap = MultiValueMap.multiValueMap(new TreeMap<String, Set>(), TreeSet.class); //  Multimap int i = 0; for(String word: words) { multiMap.put(word, i); i++; } //       System.out.println(multiMap); //  {All!=[3], Hello=[0, 2], Hi=[4], World!=[1, 5]} -   //     System.out.println(multiMap.keySet()); //  [All!, Hello, Hi, World!]    //        System.out.println("Hello = " + multiMap.get("Hello")); //  [0, 2] System.out.println("World = " + multiMap.get("World!")); //  [1, 5] System.out.println("All = " + multiMap.get("All!")); //  [3] System.out.println("Hi = " + multiMap.get("Hi")); //  [4] System.out.println("Empty = " + multiMap.get("Empty")); //  null //       System.out.println(multiMap.keySet().size()); // 4 

  String INPUT_TEXT = "Hello World! Hello All! Hi World!"; //       List<String> words = Arrays.asList(INPUT_TEXT.split(" ")); //  Multimap MultiMap<String, Integer> multiMap = MultiValueMap.multiValueMap(new LinkedHashMap<String, Set>(), LinkedHashSet.class); //  Multimap int i = 0; for(String word: words) { multiMap.put(word, i); i++; } //       System.out.println(multiMap); //  {Hello=[0, 2], World!=[1, 5], All!=[3], Hi=[4]} -    //     System.out.println(multiMap.keySet()); //  [Hello, World!, All!, Hi] -    //        System.out.println("Hello = " + multiMap.get("Hello")); //  [0, 2] System.out.println("World = " + multiMap.get("World!")); //  [1, 5] System.out.println("All = " + multiMap.get("All!")); //  [3] System.out.println("Hi = " + multiMap.get("Hi")); //  [4] System.out.println("Empty = " + multiMap.get("Empty")); //  null //       System.out.println(multiMap.keySet().size()); // 4 

  String INPUT_TEXT = "Hello World! Hello All! Hi World!"; //       List<String> words = Arrays.asList(INPUT_TEXT.split(" ")); //  Multimap MutableListMultimap<String, Integer> multiMap = new FastListMultimap<String, Integer>(); //  Multimap int i = 0; for(String word: words) { multiMap.put(word, i); i++; } //       System.out.println(multiMap); //  {Hi=[4], World!=[1, 5], Hello=[0, 2], All!=[3]}-    //     System.out.println(multiMap.keysView()); //  [Hi, Hello, World!, All!] -    //        System.out.println("Hello = " + multiMap.get("Hello")); //  [0, 2] System.out.println("World = " + multiMap.get("World!")); //  [1, 5] System.out.println("All = " + multiMap.get("All!")); //  [3] System.out.println("Hi = " + multiMap.get("Hi")); //  [4] System.out.println("Empty = " + multiMap.get("Empty")); //  [] //        System.out.println(multiMap.size()); // 6 //        System.out.println(multiMap.keysView().size()); // 4 

  String INPUT_TEXT = "Hello World! Hello All! Hi World!"; //       List<String> words = Arrays.asList(INPUT_TEXT.split(" ")); //  Multimap MutableBagMultimap<String, Integer> multiMap = new HashBagMultimap<String, Integer>(); //  Multimap int i = 0; for(String word: words) { multiMap.put(word, i); i++; } //       System.out.println(multiMap); //  {Hi=[4], World!=[1, 5], Hello=[0, 2], All!=[3]}-    //     System.out.println(multiMap.keysView()); //  [Hi, Hello, World!, All!] -    //        System.out.println("Hello = " + multiMap.get("Hello")); //  [0, 2] System.out.println("World = " + multiMap.get("World!")); //  [1, 5] System.out.println("All = " + multiMap.get("All!")); //  [3] System.out.println("Hi = " + multiMap.get("Hi")); //  [4] System.out.println("Empty = " + multiMap.get("Empty")); //  [] //        System.out.println(multiMap.size()); // 6 //        System.out.println(multiMap.keysView().size()); // 4 

  String INPUT_TEXT = "Hello World! Hello All! Hi World!"; //       List<String> words = Arrays.asList(INPUT_TEXT.split(" ")); //  Multimap MutableSortedSetMultimap<String, Integer> multiMap = new TreeSortedSetMultimap<String, Integer>(); //  Multimap int i = 0; for(String word: words) { multiMap.put(word, i); i++; } //       System.out.println(multiMap); //  {Hi=[4], World!=[1, 5], Hello=[0, 2], All!=[3]}-    //     System.out.println(multiMap.keysView()); //  [Hi, Hello, World!, All!] -    //        System.out.println("Hello = " + multiMap.get("Hello")); //  [0, 2] System.out.println("World = " + multiMap.get("World!")); //  [1, 5] System.out.println("All = " + multiMap.get("All!")); //  [3] System.out.println("Hi = " + multiMap.get("Hi")); //  [4] System.out.println("Empty = " + multiMap.get("Empty")); //  [] //        System.out.println(multiMap.size()); // 6 //        System.out.println(multiMap.keysView().size()); // 4 

  final int LIST_INDEXES_CAPACITY = 50; String INPUT_TEXT = "Hello World! Hello All! Hi World!"; //       List<String> words = Arrays.asList(INPUT_TEXT.split(" ")); //  Multimap Map<String, List<Integer>> fakeMultiMap = new HashMap<String, List<Integer>>(words.size()); //  map int i = 0; for(String word: words) { List<Integer> indexes = fakeMultiMap.get(word); if(indexes == null) { indexes = new ArrayList<Integer>(LIST_INDEXES_CAPACITY); fakeMultiMap.put(word, indexes); } indexes.add(i); i++; } //       System.out.println(fakeMultiMap); //  {Hi=[4], Hello=[0, 2], World!=[1, 5], All!=[3]} -    //     System.out.println(fakeMultiMap.keySet()); //  [Hi, Hello, World!, All!] -    //        System.out.println("Hello = " + fakeMultiMap.get("Hello")); //  [0, 2] System.out.println("World = " + fakeMultiMap.get("World!")); //  [1, 5] System.out.println("All = " + fakeMultiMap.get("All!")); //  [3] System.out.println("Hi = " + fakeMultiMap.get("Hi")); //  [4] System.out.println("Empty = " + fakeMultiMap.get("Empty")); //  null //        int cnt = 0; for(List<Integer> lists: fakeMultiMap.values()) { cnt += lists.size(); } System.out.println(cnt); // 6 //        System.out.println(fakeMultiMap.keySet().size()); // 4 

  String[] englishWords = {"one", "two", "three","ball","snow"}; String[] russianWords = {"", "", "","","c"}; //  Multiset BiMap<String, String> biMap = HashBiMap.create(englishWords.length); //  -  int i = 0; for(String englishWord: englishWords) { biMap.put(englishWord, russianWords[i]); i++; } //  -   System.out.println(biMap); //  {two=, three=, snow=c, ball=, one=} -    //     System.out.println(biMap.keySet()); //  [two, three, snow, ball, one] -    System.out.println(biMap.values()); //  [, , c, , ]-    //      System.out.println("one = " + biMap.get("one")); //  one =  System.out.println("two = " + biMap.get("two")); //  two =  System.out.println(" = " + biMap.inverse().get("")); //   = ball System.out.println(" = " + biMap.inverse().get("c")); //   = snow System.out.println("empty = " + biMap.get("empty")); //  empty = null //       System.out.println(biMap.size()); // 5 

  enum ENGLISH_WORD { ONE, TWO, THREE, BALL, SNOW } enum POLISH_WORD { JEDEN, DWA, TRZY, KULA, SNIEG } //    - ,         public static void main(String[] args) { ENGLISH_WORD[] englishWords = ENGLISH_WORD.values(); POLISH_WORD[] polishWords = POLISH_WORD.values(); //  Multiset BiMap<ENGLISH_WORD, POLISH_WORD> biMap = EnumBiMap.create(ENGLISH_WORD.class, POLISH_WORD.class); //  -  int i = 0; for(ENGLISH_WORD englishWord: englishWords) { biMap.put(englishWord, polishWords[i]); i++; } //  -   System.out.println(biMap); //  {ONE=JEDEN, TWO=DWA, THREE=TRZY, BALL=KULA, SNOW=SNIEG} //     System.out.println(biMap.keySet()); //  [ONE, TWO, THREE, BALL, SNOW] System.out.println(biMap.values()); //  [JEDEN, DWA, TRZY, KULA, SNIEG] //      System.out.println("one = " + biMap.get(ENGLISH_WORD.ONE)); //  one = JEDEN System.out.println("two = " + biMap.get(ENGLISH_WORD.TWO)); //  two = DWA System.out.println("kula = " + biMap.inverse().get(POLISH_WORD.KULA)); //  kula = BALL System.out.println("snieg = " + biMap.inverse().get(POLISH_WORD.SNIEG)); //  snieg = SNOW System.out.println("empty = " + biMap.get("empty")); //  empty = null //       System.out.println(biMap.size()); // 5 } 

  enum ENGLISH_WORD { ONE, TWO, THREE, BALL, SNOW } //    - ,         public static void main(String[] args) { ENGLISH_WORD[] englishWords = ENGLISH_WORD.values(); String[] russianWords = {"", "", "","","c"}; //  Multiset BiMap<ENGLISH_WORD, String> biMap = EnumHashBiMap.create(ENGLISH_WORD.class); //  -  int i = 0; for(ENGLISH_WORD englishWord: englishWords) { biMap.put(englishWord, russianWords[i]); i++; } //  -   System.out.println(biMap); //  {ONE=, TWO=, THREE=, BALL=, SNOW=c} //     System.out.println(biMap.keySet()); //  [ONE, TWO, THREE, BALL, SNOW] System.out.println(biMap.values()); //  [, , , , c] //      System.out.println("one = " + biMap.get(ENGLISH_WORD.ONE)); //  one =  System.out.println("two = " + biMap.get(ENGLISH_WORD.TWO)); //  two =  System.out.println(" = " + biMap.inverse().get("")); //   = BALL System.out.println(" = " + biMap.inverse().get("c")); //   = SNOW System.out.println("empty = " + biMap.get("empty")); //  empty = null //       System.out.println(biMap.size()); // 5 } 

  String[] englishWords = {"one", "two", "three","ball","snow"}; String[] russianWords = {"", "", "","","c"}; //  Multiset BidiMap<String, String> biMap = new DualHashBidiMap(); //  -  int i = 0; for(String englishWord: englishWords) { biMap.put(englishWord, russianWords[i]); i++; } //  -   System.out.println(biMap); //  {ball=, snow=c, one=, two=, three=}-    //     System.out.println(biMap.keySet()); //  [ball, snow, one, two, three]-    System.out.println(biMap.values()); //  [, c, , , ]-    //      System.out.println("one = " + biMap.get("one")); //  one =  System.out.println("two = " + biMap.get("two")); //  two =  System.out.println(" = " + biMap.getKey("")); //   = ball System.out.println(" = " + biMap.getKey("c")); //   = snow System.out.println("empty = " + biMap.get("empty")); //  empty = null //       System.out.println(biMap.size()); // 5 

  String[] englishWords = {"one", "two", "three","ball","snow"}; String[] russianWords = {"", "", "","","c"}; //  Multiset MutableBiMap<String, String> biMap = new HashBiMap(englishWords.length); //  -  int i = 0; for(String englishWord: englishWords) { biMap.put(englishWord, russianWords[i]); i++; } //  -   System.out.println(biMap); //  {two=, ball=, one=, snow=c, three=} -    //     System.out.println(biMap.keySet()); //  [snow, two, one, three, ball] -    System.out.println(biMap.values()); //  [, , , c, ] -    //      System.out.println("one = " + biMap.get("one")); //  one =  System.out.println("two = " + biMap.get("two")); //  two =  System.out.println(" = " + biMap.inverse().get("")); //   = ball System.out.println(" = " + biMap.inverse().get("c")); //   = snow System.out.println("empty = " + biMap.get("empty")); //  empty = null //       System.out.println(biMap.size()); // 5 

  String[] englishWords = {"one", "two", "three","ball","snow"}; String[] russianWords = {"", "", "","","c"}; //   BiMap Map<String, String> biMapKeys = new HashMap(englishWords.length); Map<String, String> biMapValues = new HashMap(russianWords.length); //  -  int i = 0; for(String englishWord: englishWords) { biMapKeys.put(englishWord, russianWords[i]); biMapValues.put(russianWords[i], englishWord); i++; } //  -   System.out.println(biMapKeys); //  {ball=, two=, three=, snow=c, one=}-    //     System.out.println(biMapKeys.keySet()); //  [ball, two, three, snow, one] -    System.out.println(biMapValues.keySet()); //  [, , , c, ] -    //      System.out.println("one = " + biMapKeys.get("one")); //  one =  System.out.println("two = " + biMapKeys.get("two")); //  two =  System.out.println(" = " + biMapValues.get("")); //   = ball System.out.println(" = " + biMapValues.get("c")); //   = snow System.out.println("empty = " + biMapValues.get("empty")); //  empty = null //       System.out.println(biMapKeys.size()); // 5 

  //     List<String> emptyGuava = Lists.newArrayList(); // c  guava List<String> emptyJDK = new ArrayList<>(); //  JDK MutableList<String> emptyGS = FastList.newList(); // c  gs //     100  List < String > exactly100 = Lists.newArrayListWithCapacity(100); // c  guava List<String> exactly100JDK = new ArrayList<>(100); //  JDK MutableList<String> empty100GS = FastList.newList(100); // c  gs //       100  (   100) List<String> approx100 = Lists.newArrayListWithExpectedSize(100); // c  guava List<String> approx100JDK = new ArrayList<>(115); //  JDK MutableList<String> approx100GS = FastList.newList(115); // c  gs //      List<String> withElements = Lists.newArrayList("alpha", "beta", "gamma"); // c  guava List<String> withElementsJDK = Arrays.asList("alpha", "beta", "gamma"); //  JDK MutableList<String> withElementsGS = FastList.newListWith("alpha", "beta", "gamma"); // c  gs System.out.println(withElements); System.out.println(withElementsJDK); System.out.println(withElementsGS); //      Iterable  (   ) Collection<String> collection = new HashSet<>(3); collection.add("1"); collection.add("2"); collection.add("3"); List<String> fromIterable = Lists.newArrayList(collection); // c  guava List<String> fromIterableJDK = new ArrayList<>(collection); //  JDK MutableList<String> fromIterableGS = FastList.newList(collection); // c  gs System.out.println(fromIterable); System.out.println(fromIterableJDK); System.out.println(fromIterableGS); /*    JDK   Collection ,  guava  gs  Iterable */ //    Iterator' Iterator<String> iterator = collection.iterator(); List<String> fromIterator = Lists.newArrayList(iterator); // c  guava,   JDK  System.out.println(fromIterator); //     String[] array = {"4", "5", "6"}; List<String> fromArray = Lists.newArrayList(array); // c  guava List<String> fromArrayJDK = Arrays.asList(array); //  JDK MutableList<String> fromArrayGS = FastList.newListWith(array); // c  gs System.out.println(fromArray); System.out.println(fromArrayJDK); System.out.println(fromArrayGS); //    c   MutableList<String> fromFabricGS = FastList.newWithNValues(10, () -> String.valueOf(Math.random())); // c  gs System.out.println(fromFabricGS); 

  //     Set<String> emptyGuava = Sets.newHashSet(); // c  guava Set<String> emptyJDK = new HashSet<>(); //  JDK Set<String> emptyGS = UnifiedSet.newSet(); // c  gs //       100  (   100) Set<String> approx100 = Sets.newHashSetWithExpectedSize(100); // c  guava Set<String> approx100JDK = new HashSet<>(130); //  JDK Set<String> approx100GS = UnifiedSet.newSet(130); // c  gs //      Set<String> withElements = Sets.newHashSet("alpha", "beta", "gamma"); // c  guava Set<String> withElementsJDK = new HashSet<>(Arrays.asList("alpha", "beta", "gamma")); //  JDK Set<String> withElementsGS = UnifiedSet.newSetWith("alpha", "beta", "gamma"); // c  gs System.out.println(withElements); System.out.println(withElementsJDK); System.out.println(withElementsGS); //      Iterable  (   ) Collection<String> collection = new ArrayList<>(3); collection.add("1"); collection.add("2"); collection.add("3"); Set<String> fromIterable = Sets.newHashSet(collection); // c  guava Set<String> fromIterableJDK = new HashSet<>(collection); //  JDK Set<String> fromIterableGS = UnifiedSet.newSet(collection); // c  gs System.out.println(fromIterable); System.out.println(fromIterableJDK); System.out.println(fromIterableGS); /*    JDK   Collection ,  guava  Iterable */ //    Iterator' Iterator<String> iterator = collection.iterator(); Set<String> fromIterator = Sets.newHashSet(iterator); // c  guava,   JDK  System.out.println(fromIterator); //     String[] array = {"4", "5", "6"}; Set<String> fromArray = Sets.newHashSet(array); // c  guava Set<String> fromArrayJDK = new HashSet<>(Arrays.asList(array)); //  JDK Set<String> fromArrayGS = UnifiedSet.newSetWith(array); // c  gs System.out.println(fromArray); System.out.println(fromArrayJDK); System.out.println(fromArrayGS); 

  Collection<String> collection = Lists.newArrayList("a1", "a2", "a3", "a1"); Iterable<String> iterable = collection; MutableCollection<String> collectionGS = FastList.newListWith("a1", "a2", "a3", "a1"); //     int i1 = Iterables.frequency(iterable, "a1"); //   guava int i2 = Collections.frequency(collection, "a1"); // c  JDK int i3 = CollectionUtils.cardinality("a1", iterable); // c  Apache int i4 = collectionGS.count((s) -> "a1".equals(s)); long i5 = collection.stream().filter((s) -> "a1".equals(s)).count(); // c  stream JDK System.out.println("count = " + i1 + ":" + i2 + ":" + i3 + ":" + i4 + ":" + i5); //  count = 2:2:2:2:2 

  Collection<String> collection = Lists.newArrayList("a1", "a2", "a3", "a1"); OrderedIterable<String> orderedIterable = FastList.newListWith("a1", "a2", "a3", "a1"); Iterable<String> iterable = collection; //     Iterator<String> iterator = collection.iterator(); // c  JDK String jdk = iterator.hasNext() ? iterator.next(): "1"; String guava = Iterables.getFirst(iterable, "1"); //   guava String apache = CollectionUtils.get(iterable, 0); // c  Apache String gs = orderedIterable.getFirst(); // c  GS String stream = collection.stream().findFirst().orElse("1"); // c  Stream API System.out.println("first = " + jdk + ":" + guava + ":" + apache + ":" + gs + ":" + stream); //  first = a1:a1:a1:a1:a1 

  Collection<String> collection = Lists.newArrayList("a1", "a2", "a3", "a8"); OrderedIterable<String> orderedIterable = FastList.newListWith("a1", "a2", "a3", "a8"); Iterable<String> iterable = collection; //     Iterator<String> iterator = collection.iterator(); // c  JDK String jdk = "1"; while(iterator.hasNext()) { jdk = iterator.next(); } String guava = Iterables.getLast(iterable, "1"); //   guava String apache = CollectionUtils.get(collection, collection.size()-1); // c  Apache String gs = orderedIterable.getLast(); // c  GS String stream = collection.stream().skip(collection.size()-1).findFirst().orElse("1"); // c  Stream API System.out.println("last = " + jdk + ":" + guava + ":" + apache + ":" + gs + ":" + stream); //  last = a8:a8:a8:a8:a8 

  Collection<String> collection = Lists.newArrayList("5", "1", "3", "8", "4"); OrderedIterable<String> orderedIterable = FastList.newListWith("5", "1", "3", "8", "4"); Iterable<String> iterable = collection; //     String jdk = Collections.max(collection); // c  JDK String gs = orderedIterable.max(); // c  GS String guava = Ordering.natural().max(iterable); //   guava System.out.println("max = " + jdk + ":" + guava + ":" + gs); //  max = 8:8:8 

  Collection<String> collection = Lists.newArrayList("5", "1", "3", "8", "4"); OrderedIterable<String> orderedIterable = FastList.newListWith("5", "1", "3", "8", "4"); Iterable<String> iterable = collection; //     String jdk = Collections.min(collection); // c  JDK String gs = orderedIterable.min(); // c  GS String guava = Ordering.natural().min(iterable); //   guava System.out.println("min = " + jdk + ":" + guava + ":" + gs); //  min = 1:1:1 

  Collection<String> collection = Lists.newArrayList("a3"); OrderedIterable<String> orderedIterable = FastList.newListWith("a3"); Iterable<String> iterable = collection; //     String guava = Iterables.getOnlyElement(iterable); //   guava String jdk = collection.iterator().next(); // c  JDK String apache = CollectionUtils.extractSingleton(collection); // c  Apache assert(orderedIterable.size() > 1);// c  GS String gs = orderedIterable.getFirst(); System.out.println("single = " + jdk + ":" + guava + ":" + apache + ":" + gs); //  single = a3:a3:a3:a3 

  List<String> list = Lists.newArrayList("2", "4", "13", "31", "43"); MutableList<String> mutableList = FastList.newListWith("2", "4","13", "31", "43"); //      int jdk = Collections.binarySearch(list, "13"); int guava = Ordering.natural().binarySearch(list, "13"); int gs = mutableList.binarySearch("13"); System.out.println("find = " + jdk + ":" + guava + ":" + gs); //  find = 2:2:2 

  Collection<String> collection = Lists.newArrayList("a1", "a2", "a3", "a1"); MutableCollection<String> orderedIterable = FastList.newListWith("a1", "a2", "a3", "a1"); Iterable<String> iterable = collection; //       String jdk = collection.stream().skip(2).findFirst().get(); // c  JDK String guava = Iterables.get(iterable, 2); //   guava String apache = CollectionUtils.get(iterable, 2); // c  Apache System.out.println("third = " + jdk + ":" + guava + ":" + apache); //  third = a3:a3:a3 

  Collection<String> collection = Lists.newArrayList("2", "14", "3", "13", "43"); MutableCollection<String> mutableCollection = FastList.newListWith("2", "14", "3", "13", "43"); Iterable<String> iterable = collection; //      List<String> jdk = collection.stream().filter((s) -> s.contains("1")).collect(Collectors.toList()); // c  JDK Iterable<String> guava = Iterables.filter(iterable, (s) -> s.contains("1")); //   guava Collection<String> apache = CollectionUtils.select(iterable, (s) -> s.contains("1")); // c  Apache MutableCollection<String> gs = mutableCollection.select((s) -> s.contains("1")); // c  GS System.out.println("select = " + jdk + ":" + guava + ":" + apache + ":" + gs); //  select = [14, 13]:[14, 13]:[14, 13]:[14, 13] 

  Collection<String> collection1 = Lists.newArrayList("a1", "a2", "a3", "a1"); Collection<String> collection2 = Lists.newArrayList("a1", "a2", "a3", "a1"); Iterable<String> iterable1 = collection1; Iterable<String> iterable2 = collection2; MutableCollection<String> mutableCollection1 = FastList.newListWith("a1", "a2", "a3", "a1"); MutableCollection<String> mutableCollection2 = FastList.newListWith("a1", "a2", "a3", "a1"); //      boolean jdk = collection1.containsAll(collection2); // c  JDK boolean guava = Iterables.elementsEqual(iterable1, iterable2); //   guava boolean apache = CollectionUtils.containsAll(collection1, collection2); // c  Apache boolean gs = mutableCollection1.containsAll(mutableCollection2); // c  GS System.out.println("containsAll = " + jdk + ":" + guava + ":" + apache + ":" + gs); //  containsAll = true:true:true:true 

  Collection<String> collection1 = Lists.newArrayList("a1", "a2", "a3", "a1"); Collection<String> collection2 = Lists.newArrayList("a4", "a8", "a3", "a5"); Set<String> set1 = Sets.newHashSet("a1", "a2", "a3", "a1"); Set<String> set2 = Sets.newHashSet("a4", "a8", "a3", "a5"); MutableSet<String> mutableSet1 = UnifiedSet.newSetWith("a1", "a2", "a3", "a1"); MutableSet<String> mutableSet2 = UnifiedSet.newSetWith("a4", "a8", "a3", "a5"); //           boolean jdk = !Collections.disjoint(collection1, collection2); // c  JDK boolean guava = !Sets.intersection(set1, set2).isEmpty(); //   guava boolean apache = CollectionUtils.containsAny(collection1, collection2); // c  Apache boolean gs = !mutableSet1.intersect(mutableSet2).isEmpty(); // c  GS System.out.println("containsAny = " + jdk + ":" + guava + ":" + apache + ":" + gs); //  containsAny = true:true:true:true 

  Collection<String> collection1 = Lists.newArrayList("a1", "a2", "a3", "a1"); Collection<String> collection2 = Lists.newArrayList("a4", "a8", "a3", "a5"); Set<String> set1 = Sets.newHashSet("a1", "a2", "a3", "a1"); Set<String> set2 = Sets.newHashSet("a4", "a8", "a3", "a5"); MutableSet<String> mutableSet1 = UnifiedSet.newSetWith("a1", "a2", "a3", "a1"); MutableSet<String> mutableSet2 = UnifiedSet.newSetWith("a4", "a8", "a3", "a5"); //        Set<String> jdk = new HashSet<>(set1); // c  JDK jdk.retainAll(set2); Set<String> guava = Sets.intersection(set1, set2); //   guava Collection<String> apache = CollectionUtils.intersection(collection1, collection2); // c  Apache Set<String> gs = mutableSet1.intersect(mutableSet2); // c  GS System.out.println("intersect = " + jdk + ":" + guava + ":" + apache + ":" + gs); //  intersect = [a3]:[a3]:[a3]:[a3] 

  Collection<String> collection1 = Lists.newArrayList("a2", "a3"); Collection<String> collection2 = Lists.newArrayList("a8", "a3", "a5"); Set<String> set1 = Sets.newHashSet("a2", "a3"); Set<String> set2 = Sets.newHashSet("a8", "a3", "a5"); MutableSet<String> mutableSet1 = UnifiedSet.newSetWith("a2", "a3"); MutableSet<String> mutableSet2 = UnifiedSet.newSetWith("a8", "a3", "a5"); //   ,          (difference) Set<String> jdk = new HashSet<>(set1); // c  JDK jdk.removeAll(set2); Set<String> guava = Sets.difference(set1, set2); //   guava Collection<String> apache = CollectionUtils.removeAll(collection1, collection2); // c  Apache Set<String> gs = mutableSet1.difference(mutableSet2); // c  GS System.out.println("difference = " + jdk + ":" + guava + ":" + apache + ":" + gs); //  difference = [a2]:[a2]:[a2]:[a2] 

  Collection<String> collection1 = Lists.newArrayList("a2", "a3"); Collection<String> collection2 = Lists.newArrayList("a8", "a3", "a5"); Set<String> set1 = Sets.newHashSet("a2", "a3"); Set<String> set2 = Sets.newHashSet("a8", "a3", "a5"); MutableSet<String> mutableSet1 = UnifiedSet.newSetWith("a2", "a3"); MutableSet<String> mutableSet2 = UnifiedSet.newSetWith("a8", "a3", "a5"); //     (symmetric difference)    Set<String> intersect = new HashSet<>(set1); // c  JDK intersect.retainAll(set2); Set<String> jdk = new HashSet<>(set1); jdk.addAll(set2); jdk.removeAll(intersect); Set<String> guava = Sets.symmetricDifference(set1, set2); //   guava Collection<String> apache = CollectionUtils.disjunction(collection1, collection2); // c  Apache Set<String> gs = mutableSet1.symmetricDifference(mutableSet2); // c  GS System.out.println("symmetricDifference = " + jdk + ":" + guava + ":" + apache + ":" + gs); //  symmetricDifference = [a2, a5, a8]:[a2, a5, a8]:[a2, a5, a8]:[a2, a5, a8] 

  Set<String> set1 = Sets.newHashSet("a1", "a2"); Set<String> set2 = Sets.newHashSet("a4"); MutableSet<String> mutableSet1 = UnifiedSet.newSetWith("a1", "a2"); MutableSet<String> mutableSet2 = UnifiedSet.newSetWith("a4"); Collection<String> collection1 = set1; Collection<String> collection2 = set2; //     Set<String> jdk = new HashSet<>(set1); // c  JDK jdk.addAll(set2); Set<String> guava = Sets.union(set1, set2); //   guava Collection<String> apache = CollectionUtils.union(collection1, collection2); // c  Apache Set<String> gs = mutableSet1.union(mutableSet2); // c  GS System.out.println("union = " + jdk + ":" + guava + ":" + apache + ":" + gs); //  union = [a1, a2, a4]:[a1, a2, a4]:[a1, a2, a4]:[a1, a2, a4] 

  List<String> jdk = Lists.newArrayList("a1", "a2", "a3", "a1"); Iterable<String> iterable = jdk; MutableList<String> gs = FastList.newList(jdk); //   Collections.sort(jdk); //   jdk List<String> guava = Ordering.natural().sortedCopy(iterable); //   guava gs.sortThis(); // c  gs System.out.println("sort = " + jdk + ":" + guava + ":" + gs); //  sort = [a1, a1, a2, a3]:[a1, a1, a2, a3]:[a1, a1, a2, a3] 

  Collection<String> jdk = Lists.newArrayList("a1", "a2", "a3", "a1"); Iterable<String> guava = Lists.newArrayList(jdk); Iterable<String> apache = Lists.newArrayList(jdk); MutableCollection<String> gs = FastList.newList(jdk); //      jdk.removeIf((s) -> s.contains("1")); //   jdk Iterables.removeIf(guava, (s) -> s.contains("1")); //   guava CollectionUtils.filter(apache, (s) -> !s.contains("1")); //   apache gs.removeIf((Predicate<String>) (s) -> s.contains("1")); // c  gs System.out.println("removeIf = " + jdk + ":" + guava + ":" + apache + ":" + gs); //  removeIf = [a2, a3]:[a2, a3]:[a2, a3]:[a2, a3] 

  Collection<String> jdk = Lists.newArrayList("a1", "a2", "a3", "a1"); Iterable<String> guava = Lists.newArrayList(jdk); Iterable<String> apache = Lists.newArrayList(jdk); MutableCollection<String> gs = FastList.newList(jdk); //       jdk.removeIf((s) -> !s.contains("1")); //   jdk Iterables.removeIf(guava, (s) -> !s.contains("1")); //   guava CollectionUtils.filter(apache, (s) -> s.contains("1")); //   apache gs.removeIf((Predicate<String>) (s) -> !s.contains("1")); // c  gs System.out.println("retainIf = " + jdk + ":" + guava + ":" + apache + ":" + gs); //  retainIf = [a1, a1]:[a1, a1]:[a1, a1]:[a1, a1] 

  Collection<String> collection = Lists.newArrayList("a1", "a2", "a3", "a1"); Iterable<String> iterable = collection; Collection<String> apache = Lists.newArrayList(collection); MutableCollection<String> mutableCollection = FastList.newList(collection); //        List<String> jdk = collection.stream().map((s) -> s + "_1").collect(Collectors.toList()); //   jdk Iterable<String> guava = Iterables.transform(iterable, (s) -> s + "_1"); //   guava CollectionUtils.transform(apache, (s) -> s + "_1"); //   apache MutableCollection<String> gs = mutableCollection.collect((s) -> s + "_1"); // c  gs System.out.println("transform = " + jdk + ":" + guava + ":" + apache + ":" + gs); //  transform = [a1_1, a2_1, a3_1, a1_1]:[a1_1, a2_1, a3_1, a1_1]:[a1_1, a2_1, a3_1, a1_1]:[a1_1, a2_1, a3_1, a1_1] 

  Collection<StringBuilder> jdk = Lists.newArrayList(new StringBuilder("a1"), new StringBuilder("a2"), new StringBuilder("a3")); Iterable<StringBuilder> iterable = Lists.newArrayList(new StringBuilder("a1"), new StringBuilder("a2"), new StringBuilder("a3"));; Collection<StringBuilder> apache = Lists.newArrayList(new StringBuilder("a1"), new StringBuilder("a2"), new StringBuilder("a3")); MutableCollection<StringBuilder> gs = FastList.newListWith(new StringBuilder("a1"), new StringBuilder("a2"), new StringBuilder("a3")); //      jdk.stream().forEach((s) -> s.append("_1")); //   jdk Iterable<StringBuilder> guava = Iterables.transform(iterable, (s) -> s.append("_1")); //   guava CollectionUtils.transform(apache, (s) -> s.append("_1")); //   apache gs.forEach((Procedure<StringBuilder>) (s) -> s.append("_1")); // c  gs System.out.println("change = " + jdk + ":" + guava + ":" + apache + ":" + gs); // changeAll = [a1_1, a2_1, a3_1]:[a1_1, a2_1, a3_1]:[a1_1, a2_1, a3_1]:[a1_1, a2_1, a3_1]