Declare Soft
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## Declare Soft

The semantics of the `declare soft` statement have been refined in AspectJ 5 to only soften exceptions that are not already runtime exceptions. If the exception type specified in a declare soft statement is `RuntimeException` or a subtype of `RuntimeException` then a new XLint warning will be issued:

           	  declare soft : SomeRuntimeException : execution(* *(..));

           	  >> "SomeRuntimeException will not be softened as it is already a RuntimeException" [XLint:runtimeExceptionNotSoftened]

This XLint message can be controlled by setting the `runtimeExceptionNotSoftened` XLint parameter.

If the exception type specified in a declare soft statement is a super type of `RuntimeException` (such as `Exception` for example) then any checked exception thrown at a matched join point, where the exception is an instance of the softened exception, will be softened to an `org.aspectj.lang.SoftException`.

           	public aspect SoftenExample {

           	  declare soft : Exception : execution(* Foo.*(..));

           	}

           	class Foo {

           	  public static void main(String[] args) {
           	    Foo foo = new Foo();
           	    foo.foo();
           	    foo.bar();
           	  }

           	  void foo() throws Exception {
           	    throw new Exception();        // this will be converted to a SoftException
           	  }

           	  void bar() throws Exception {
           	    throw new RuntimeException();  // this will remain a RuntimeException
           	  }

           	}

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