Eclipse Collections - Features you want with the collections you need.

//Initializing mutable list with empty(), of(), with() method
MutableList<String> mutableListEmpty =
  Lists.mutable.empty();
MutableList<String> mutableListOf =
  Lists.mutable.of("One", "One", "Two", "Three");
MutableList<String> mutableListWith =
  Lists.mutable.with("One", "One", "Two", "Three");

//Various container types available
MutableSet<String> mutableSet =
  Sets.mutable.with("One", "One", "Two", "Three");
MutableBag<String> mutableBag =
  Bags.mutable.with("One", "One", "Two", "Three");
MutableStack<String> mutableStack =
  Stacks.mutable.with("One", "One", "Two", "Three");
MutableMap<String, String> mutableMap =
  Maps.mutable.with("key1", "value1", "key2", "value2", "key3", "value3");
MutableMultimap<String, String> multimapWithList =
  Multimaps.mutable.list.with("key1", "value1-1", "key1", "value1-2", "key2","value2-1");
MutableBiMap<String, String> mutableBiMap =
  BiMaps.mutable.with("key1", "value1", "key2", "value2", "key3", "value3");
//Initializing immutable list with empty(), of(), with() method
ImmutableList<String> immutableListEmpty =
  Lists.immutable.empty();
ImmutableList<String> immutableListOf =
  Lists.immutable.of("One", "One", "Two", "Three");
ImmutableList<String> immutableListWith =
  Lists.immutable.with("One", "One", "Two", "Three");

//Various container types available
ImmutableSet<String> immutableSet =
  Sets.immutable.with("One", "One", "Two", "Three");
ImmutableBag<String> immutableBag =
  Bags.immutable.with("One", "One", "Two", "Three");
ImmutableStack<String> immutableStack =
  Stacks.immutable.with("One", "One", "Two", "Three");
ImmutableMap<String, String> immutableMap =
  Maps.immutable.with("key1", "value1", "key2", "value2", "key3", "value3");
ImmutableMultimap<String, String> immutableMultimapWithList =
  Multimaps.immutable.list.with("key1", "value1-1", "key1", "value1-2", "key2","value2-1");
ImmutableBiMap<String, String> immutableBiMap =
  BiMaps.immutable.with("key1", "value1", "key2", "value2", "key3", "value3");
//Mutable and immutable Lists, Sets, Bags, Stacks and Maps are available for all 8 primitive types
MutableIntList intList =
  IntLists.mutable.of(1, 2, 3);
MutableLongList longList =
  LongLists.mutable.of(1L, 2L, 3L);
MutableCharList charList =
  CharLists.mutable.of('a', 'b', 'c');
MutableShortList shortList =
  ShortLists.mutable.of((short)1, (short)2, (short)3);
MutableByteList byteList =
  ByteLists.mutable.of((byte)1, (byte)2, (byte)3);
MutableBooleanList booleanList =
  BooleanLists.mutable.of(true, false);
MutableFloatList floatList =
  FloatLists.mutable.of(1.0f, 2.0f, 3.0f);
MutableDoubleList doubleList =
  DoubleLists.mutable.of(1.0, 2.0, 3.0);

//You can create a ranged ints with IntInterval
IntInterval oneTo10 =
  IntInterval.fromTo(1, 10); // ints from 1 to 10
// [1, 2, 3, 4, 5, 6, 7, 8, 9, 10]
IntInterval oneTo10By3 =
  IntInterval.fromToBy(1, 10, 3); // ints from 1 to 10 step by 3
// [1, 4, 7, 10]
IntInterval oddsFrom1To10 =
  IntInterval.oddsFromTo(1, 10); // odd ints from 1 to 10
// [1, 3, 5, 7, 9]
IntInterval evensFrom1To10 =
  IntInterval.evensFromTo(1, 10); // even ints from 1 to 10
// [2, 4, 6, 8, 10]