#hacktoberfest SerializeInterceptor - Unit Tests Coverage and Bug Fix

[cho8]

Issue #60 -- Increased Code Coverage.
Fixed a bug where file mime returned always included delimiter.
Refactored and added unit tests.

[coveralls]

Coverage increased (+0.2%) to 44.821% when pulling ba0fbd7 on cho8:serialize-interceptor-tests into eaeb2e6 on intuit:develop.

[cho8]

@diana-derose Can I get some feedback on this PR?

[diana-derose]

@cho8 - Could you explain what was the bug in the getMime method?

[cho8]

@diana-derose The getMime method was returning the delimiter when it parses for the file mime.

The beginIndex in substring(int beginIndex, int endIndex) is inclusive. In the case of getMime, this means it will include the delimiter when it parses out the mime on line 205:
return name.substring(name.lastIndexOf(delimiter), name.length());

e.g. filename.jpg would result in .jpg instead of just jpg

If the file uploaded is an image, the image content would never be retrieved as intended since the returned mime would never match a known image type from line 49
private static final String[] IMAGE_MIMES = {"jpg", "jpeg", "tif", "tiff", "gif", "png", "bmp"};

This PR fixes this issue by incrementing the beginIndex by 1
return name.substring(name.lastIndexOf(delimiter) + 1, name.length());

[cho8]

The above is also true for when getMime is used to check content-type
e.g. 'image/jpg would have returned as /jpg

[diana-derose]

@cho8 - Thanks for the details, I have approved it.