guava之Multiset

可重复set和map,便于计数

可变集合接口	属于JDK还是Guava	不可变版本
Collection	JDK	ImmutableCollection
List	JDK	ImmutableList
Set	JDK	ImmutableSet
SortedSet/NavigableSet	JDK	ImmutableSortedSet
Map	JDK	ImmutableMap
SortedMap	JDK	ImmutableSortedMap
Multiset	Guava	ImmutableMultiset
SortedMultiset	Guava	ImmutableSortedMultiset
Multimap	Guava	ImmutableMultimap
ListMultimap	Guava	ImmutableListMultimap
SetMultimap	Guava	ImmutableSetMultimap
BiMap	Guava	ImmutableBiMap
ClassToInstanceMap	Guava	ImmutableClassToInstanceMap
Table	Guava	ImmutableTable

Multiset<String> m = HashMultiset.create();
m.add("a");
m.add("a");
m.add("a");
m.add("b");
m.add("b");
m.add("c");
m.add("d",5);
Set<String> set = m.elementSet();

Set<Multiset.Entry<String>> entrys  = m.entrySet();
System.out.println(set);

entrys.forEach(entry-> System.out.println(entry.getElement()+"-->"+entry.getCount()));

m.remove("a");
System.out.println("a-->"+m.count("a"));

m.setCount("a",100);
System.out.println("a-->"+m.count("a"));

m.setCount("a",10,1);
System.out.println("a-->"+m.count("a"));

m.setCount("a",100,1);
System.out.println("a-->"+m.count("a"));

结果:

[a, b, c, d]
a-->3
b-->2
c-->1
d-->5
a-->2
a-->100
a-->100
a-->1