This rule raises an issue when a lambda expression uses block notation while expression notation could be used.
The right-hand side of a lambda expression can be written in two ways:
(a, b) → a + b
(a, b)
→ {return a + b;}
By convention, expression notation is preferred over block notation. Block notation must be used when the function implementation requires more
than one statement. However, when the code block consists of only one statement (which may or may not be a return
statement), it can be
rewritten using expression notation.
This convention exists because expression notation has a cleaner, more concise, functional programming style and is regarded as more readable.
return
statement, replace the code block with the argument expression from the
return
statement. return
statement, replace the code block with that statement. (a, b) -> { return a + b; } // Noncompliant, replace code block with expression
(a, b) -> a + b // Compliant
x -> {System.out.println(x+1);} // Noncompliant, replace code block with statement
x -> System.out.println(x+1) // Compliant