Servlet exception in external preview

[szolo]

Steps to reproduce

User reported that there are exceptions in external preview while accessing project styles and mixins.

See Intercom (thread also contain attached images):

• https://app.intercom.io/a/apps/y0ueytrp/inbox/inbox/all/conversations/23086209381
• https://app.intercom.io/a/apps/y0ueytrp/inbox/inbox/all/conversations/23086226118
• https://app.intercom.io/a/apps/y0ueytrp/inbox/inbox/all/conversations/23086862974

Actual behavior

Throwable.<init>() line: 251
Exception.<init>() line: 54
RuntimeException.<init>() line: 51
NullPointerException.<init>() line: 60
ProjectServlet.isResourceAvailable(String) line: 314
ProjectServlet.doGet(HttpServletRequest, HttpServletResponse) line: 109
HttpServlet.service(HttpServletRequest, HttpServletResponse) line: 687
HttpServlet.srvice(ServletRequest, ServletResponse) line: 790
ServletHolder.handle(Request, ServletRequest, ServletResponse) line: 848
ServletHandler$CachedChain.doFilter(ServletRequest, ServletResponse) line: 1772

Expected behavior

No exception.

IDE, Designer and OS version

OS: Windows 10 10.0 amd64
Browser: Mozilla/5.0 (Windows NT 6.2; Win64; x64; Trident/7.0; rv:11.0) like Gecko
Java: 1.8.0_161
Eclipse: org.eclipse.epp.package.jee.product 4.12.0.20190614-1200
Designer: 4.3.2

[stale]

Hello there!

It looks like this issue hasn't progressed lately. There are so many issues that we just can't deal them all within a reasonable timeframe.

There are a few things you could help to get things rolling on this issue (this is an automated message, so expect that some of these are already in use):

• Check if the issue is still valid for the latest version. There are many duplicates in our issue tracker, so it is possible that the issue is already tackled.
• Provide more details how to reproduce the issue.
• Explain why it is important to get this issue fixed and politely draw others attention to it e.g. via the forum or social media.
• Add a reduced test case about the issue, so it is easier for somebody to start working on a solution.
• If the issue is clearly a bug, use the Warranty in your Vaadin subscription to raise its priority.

Thanks again for your contributions! Even though we haven't been able to get this issue fixed, we hope you to report your findings and enhancement ideas in the future too!

[stale]

Hello there!

It looks like this issue hasn't progressed lately. There are so many issues that we just can't deal them all within a reasonable timeframe.

There are a few things you could help to get things rolling on this issue (this is an automated message, so expect that some of these are already in use):

• Check if the issue is still valid for the latest version. There are many duplicates in our issue tracker, so it is possible that the issue is already tackled.
• Provide more details how to reproduce the issue.
• Explain why it is important to get this issue fixed and politely draw others attention to it e.g. via the forum or social media.
• Add a reduced test case about the issue, so it is easier for somebody to start working on a solution.
• If the issue is clearly a bug, use the Warranty in your Vaadin subscription to raise its priority.

Thanks again for your contributions! Even though we haven't been able to get this issue fixed, we hope you to report your findings and enhancement ideas in the future too!