GitHub user krishna-pandey opened a pull request: https://github.com/apache/zeppelin/pull/2564
[ZEPPELIN-2896] Replacing addHeader with setHeader method in CorsFilter.java ### What is this PR for? HTTP Response Headers were being added multiple times. Replacing addHeader method with setHeader overrides the Response Header value with new/existing value instead of adding another duplicate response Header. ### What type of PR is it? [Bug Fix] ### What is the Jira issue? * https://issues.apache.org/jira/browse/ZEPPELIN-2896 ### How should this be tested? Open the Zeppelin URL in Chrome Browser. Select "More Tools" -> "Developer Tools" from the right-side menu. Under Network Section, select the request with name "localhost" and check for "Response Headers". You should see response headers appearing only once.  You can merge this pull request into a Git repository by running: $ git pull https://github.com/krishna-pandey/zeppelin ZEPPELIN-2896 Alternatively you can review and apply these changes as the patch at: https://github.com/apache/zeppelin/pull/2564.patch To close this pull request, make a commit to your master/trunk branch with (at least) the following in the commit message: This closes #2564 ---- commit 89a3fdcd3994070f872ca755587a0f10f76c6917 Author: krishna-pandey <krish.pande...@gmail.com> Date: 2017-09-04T09:39:59Z replacing addHeader with setHeader ---- ---