rspec/rules/S2293/java/rule.adoc

== Why is this an issue?

Java 7 introduced the diamond operator (``++<>++``) to reduce the verbosity of generics code. For instance, instead of having to declare a ``++List++``'s type in both its declaration and its constructor, you can now simplify the constructor declaration with ``++<>++``, and the compiler will infer the type.


*Note* that this rule is automatically disabled when the project's ``++sonar.java.source++`` is lower than ``++7++``.


=== Noncompliant code example

[source,java]
----
List<String> strings = new ArrayList<String>();  // Noncompliant
Map<String,List<Integer>> map = new HashMap<String,List<Integer>>();  // Noncompliant
----


=== Compliant solution

[source,java]
----
List<String> strings = new ArrayList<>();
Map<String,List<Integer>> map = new HashMap<>();
----


ifdef::env-github,rspecator-view[]

'''
== Implementation Specification
(visible only on this page)

=== Message

Replace the type specification in this constructor call with the diamond operator ("<>"). [(sonar.java.source not set. Assuming 7 or greater.)]


'''
== Comments And Links
(visible only on this page)

=== on 17 Dec 2014, 13:55:04 Nicolas Peru wrote:
Fine by me. This rule should probably be implemented only when we have figured a way to activate rules depending on version of java used.

=== on 17 Dec 2014, 14:46:31 Ann Campbell wrote:
\[~nicolas.peru] I've set it to off by default & tagged it java7 just like some of the other Java 7/8-specific rules. I think this could be implemented now & we trust the user to turn it on only when indicated.

endif::env-github,rspecator-view[]