As of java 1.7 the java language specification allows integer literals to contain underscores in order to make them more readable. If it is applied in a good way it can enormously increase the readability of your code.

In java 1.6 one had to define integer literals like this:

With java 1.7 such integer literals can be written more readably by using the underscore as a  thousands separators.

or when using binary literals one can use the underscores to group bytes

 

Further information can be found at


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