1

is there any difference between : 

TreeMap<String, String> myMap = new TreeMap<>();

and

TreeMap<String, String> myMap = new TreeMap<String,String>();

Thanks!

Sreenath S
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Huy Than
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3 Answers3

2

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().

cyon
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1

First one will only work in Java 7, the second one from Java 5+

Elchin
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  • Although note that since Generics are only used at compile-time, and don't exist in the byte-code, code using only Java-6 features plus the diamond operator, and compiled with a Java 7 compiler will run on a Java 6 JVM. – Edd Feb 01 '13 at 10:34
1

No difference at all..! Its just a language construct. <> is newly introduced operator known as diamond operator from java 7.

Priyank Doshi
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