Multiple code improvements - squid:S1192, squid:S1166, squid:S1172, squid:S1213, squid:S1155, squid:UselessImportCheck

[georgekankava]

This pull request is focused on resolving occurrences of Sonar rules
squid:S1192 - String literals should not be duplicated.
squid:S1166 - Exception handlers should preserve the original exception.
squid:S1172 - Unused method parameters should be removed.
squid:S1213 - The members of an interface declaration or class should appear in a pre-defined order.
squid:S1155 - Collection.isEmpty() should be used to test for emptiness.
squid:UselessImportCheck - Useless imports should be removed.
This pull request removes 42 minutes of technical debt.
You can find more information about the issue here:
https://dev.eclipse.org/sonar/rules/show/squid:S1192
https://dev.eclipse.org/sonar/rules/show/squid:S1166
https://dev.eclipse.org/sonar/rules/show/squid:S1172
https://dev.eclipse.org/sonar/rules/show/squid:S1213
https://dev.eclipse.org/sonar/rules/show/squid:S1155
https://dev.eclipse.org/sonar/rules/show/squid:UselessImportCheck
Please let me know if you have any questions.
George Kankava

[balamurugana]

@harshavardhana please check whether its ok.

[balamurugana]

You would need to fix appveyor/travis-ci builds

[balamurugana]

I see HeaderParser is not used here. Is this import needed?

[balamurugana]

@georgekankava please rebase this pull request.

[georgekankava]

@balamurugana sorry for the delay. I have rebased the PR.

[balamurugana]

LGTM. Please fix below stylecheck error from gradle build

:checkstyleMain[ant:checkstyle] /home/bala/java/src/github.com/minio-java/src/main/java/io/minio/Digest.java:35: First sentence should be present.
[ant:checkstyle] /home/bala/java/src/github.com/minio-java/src/main/java/io/minio/Digest.java:186: First sentence should be present.
[ant:checkstyle] /home/bala/java/src/github.com/minio-java/src/main/java/io/minio/Digest.java:189: At-clause should have a non-empty description.
[ant:checkstyle] /home/bala/java/src/github.com/minio-java/src/main/java/io/minio/Digest.java:190: At-clause should have a non-empty description.
[ant:checkstyle] /home/bala/java/src/github.com/minio-java/src/main/java/io/minio/Digest.java:191: At-clause should have a non-empty description.
[ant:checkstyle] /home/bala/java/src/github.com/minio-java/src/main/java/io/minio/Digest.java:192: At-clause should have a non-empty description.
[ant:checkstyle] /home/bala/java/src/github.com/minio-java/src/main/java/io/minio/Digest.java:193: At-clause should have a non-empty description.
[ant:checkstyle] /home/bala/java/src/github.com/minio-java/src/main/java/io/minio/Digest.java:194: At-clause should have a non-empty description.
[ant:checkstyle] /home/bala/java/src/github.com/minio-java/src/main/java/io/minio/Digest.java:195: At-clause should have a non-empty description.
[ant:checkstyle] /home/bala/java/src/github.com/minio-java/src/main/java/io/minio/Digest.java:196: At-clause should have a non-empty description.
[ant:checkstyle] /home/bala/java/src/github.com/minio-java/src/main/java/io/minio/Digest.java:197: At-clause should have a non-empty description.
[ant:checkstyle] /home/bala/java/src/github.com/minio-java/src/main/java/io/minio/Digest.java:236:9: WhitespaceAround: 'if' is not followed by whitespace.
[ant:checkstyle] /home/bala/java/src/github.com/minio-java/src/main/java/io/minio/Digest.java:239:9: WhitespaceAround: 'if' is not followed by whitespace.

[georgekankava]

@balamurugana I am about to fix the checkstyle errors.

[georgekankava]

@balamurugana updated.

[abperiasamy]

LGTM