IO-724 FileUtils#deleteDirectory(File) exception Javadoc inaccurate update

[liran2000]

FileUtils.deleteDirectory javadoc is inaccurate for nonexistent directory.

Change for returned exception javadoc, as the conditions at the method implementation do not match the javadoc.

Method implementation does not throws the IllegalArgumentException from the javadoc if directory does not exist:
if (!directory.exists()) {
return;
}

This one line code proves it:
FileUtils.deleteDirectory(new File("nonexistingdir"));

[XenoAmess]

Thinng about this will be better when after we apply JSR305

If my memory be correct, there be a branch adding these annotations to suggest Nullable or NotNull.

How's it going @garydgregory ?

[liran2000]

Thinng about this will be better when after we apply JSR305

If my memory be correct, there be a branch adding these annotations to suggest Nullable or NotNull.

The most important here is to remove the "IllegalArgumentException" if directory does not exist from the javadoc, which does not match the implementation condition: if (!directory.exists()) { return;}

Regarding Nullable/NotNull, got it, removed this addition for now.

[coveralls]

Coverage remained the same at 89.25% when pulling eb4d3c8 on liran2000:IO-724-javadoc into ff02373 on apache:master.

[garydgregory]

Thinng about this will be better when after we apply JSR305

If my memory be correct, there be a branch adding these annotations to suggest Nullable or NotNull.

How's it going @garydgregory ?

Fixing Javadoc here is good. JSR305/8 is a different story, which we are not doing for now.

[liran2000]

@XenoAmess @garydgregory thank you, can you then please review and merge this PR ?

[garydgregory]

@XenoAmess @garydgregory thank you, can you then please review and merge this PR ?

I should be able to look at this later today, AFK ATM.

[liran2000]

@XenoAmess @garydgregory thank you, can you then please review and merge this PR ?

I should be able to look at this later today, AFK ATM.

@garydgregory thanks, will wait for your review and merge.