Fail to detect exception class in try catch block

[csoroiu]

I spotted 2 issues with try...catch blocks.
As a context i am using master version and the java15/java16 as signatures.

1. First is related to the fact that animal-sniffer is not reporting an exception class not available in java < 1.7. There should be an error reported on line 5, as java.lang.ReflectiveOperationException is not present in java 5 & 6 for the code below.

public void exceptionClassNotAvailableInJava6() {
    try {
        Method method = TestClass.class.getDeclaredMethod("emptyMethod");
        method.invoke(null);
    } catch (ReflectiveOperationException exception) {
        logException(exception);
    }
}

2. The second is a little bit trickier. The effect of the below multi-catch statement is that the runtime type of the exception variable, when compiled with java7 or 8, is java.lang.ReflectiveOperationException and the frame that is generated contains java.lang.ReflectiveOperationException on the stack. Same as above, there should be an error reported on line 5, as java.lang.ReflectiveOperationException is not present in java 5 & 6 for the code below. That particular exception was added in the middle of the hierarchy in Java 7.

public void exceptionMultiCatch() {
    try {
        Method method = TestClass.class.getDeclaredMethod("emptyMethod");
        method.invoke(null);
    } catch (NoSuchMethodException | IllegalAccessException | InvocationTargetException exception) {
        logException(exception);
    }
}

Both code block from above pass the check even if they should not.
I'll post a PR soon on this matter.

[csoroiu]

fixed by #47