问题
is there any difference between :
TreeMap<String, String> myMap = new TreeMap<>();
and
TreeMap<String, String> myMap = new TreeMap<String,String>();
Thanks!
回答1:
They are the same in java 7 where the diamond operator <> was introduced. In older versions of java the diamond operator will not work.
The diamond operator brings type inference to constructors. Type inference on generic methods is available in java 5 and higher. Prior to java 7, to create a generic class using the compiler's type inference you had to use generic factory methods like static <K,T> Map<K,T> createMap().
回答2:
First one will only work in Java 7, the second one from Java 5+
回答3:
No difference at all..! Its just a language construct. <> is newly introduced operator known as diamond operator from java 7.
来源：https://stackoverflow.com/questions/12857129/java-collection-constructor