Maps

• Maps.uniqueIndex()将列表转换为map 

 //iterator各个元素作为Map.values, key为Function.apply返回值
 Maps.uniqueIndex(ps.iterator(), new Function<Person, String>() {
     @Override
     public String apply(Person p) {
         return p.getName();
     }
 });

• Maps.asMap()，<K, V>和Maps.uniqueIndex()相反

 Maps.asMap(ps, new Function<Person, String>() {
     @Override
     public String apply(Person p) {
         return p.getName();
     }
 });

• Maps Transform API:

Maps.transformEntries(map, new Maps.EntryTransformer<String, Boolean, String>() {
    @Override
    public String transformEntry(String key, Boolean value) {
        return value ? "yes" : "no";
    }
}); 将Map<String, Boolean> --> Map<String, String>, 其他的还有Maps.transformValues转换值