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What does <> mean for java generics?

I have a bit of code:

class MyClass<RCM> 
  private List<RCM> allPreExistingConfigsForCodes() {
    if(this.allCodesForThisType.size() == 0)
       return new ArrayList<RCM>(0);

IntelliJ is telling me I should replace new ArrayList<RCM> with new ArrayList<> what would that mean?

question from:https://stackoverflow.com/questions/8660202/what-does-mean-for-java-generics

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From the Java Tutorials generics lesson:

In Java SE 7 and later, you can replace the type arguments required to invoke the constructor of a generic class with an empty set of type arguments (<>) as long as the compiler can determine, or infer, the type arguments from the context. This pair of angle brackets, <>, is informally called the diamond. For example, you can create an instance of Box<Integer> with the following statement:

Box<Integer> integerBox = new Box<>();


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