[FIXED] unable to hotswap html file in Intellij with tomcat 9

Issue

I am new to IntelliJ, and I created a run configuration to debug my web application using intellij.

What I did are:

1. ran my application on intellij debug mode, and saw server start up successfully, html file got rendered correctly.
   2. modified a java file.
   3. modified a html file.
   4. saved them.
   5. clicked somewhere outside the intellij window to trigger hotswap.
   6. I saw message pop up saying only 1 file updated (It was the java file).

The issue I found is:

1. The html never got updated.

What I noticed are:

1. the java file was recompiled and "hotswapped" successfully.
   2. the html file was not "hotswapped":
      • The page in browser did not reflect the change I made.
      • html did not update even I manually refresh the web page in browser.
      • if i modify only the html file in IntelliJ, pop up alwasy would always say "loaded classes are up to date. Nothing to upload".
   3. but I verified html source is successfully changed, and the html file being deployed to the exploded war directory was also successfully changed.
   4. when I clicked the "redeploy" button, then I could see the html get updated.
   5. I have also tried adding cachingAllowed="false" to tomcat context.xml file, but no luck.

My questions are:

1. How to enable hotswap in IntelliJ with tomcat9? (Did I miss anything?)
   2. What is the difference between "hotswap" and "redeploy"?

Thanks.

IntelliJ version: Ultimate 2018.1

Tomcat version: apache-tomcat-9.0.7

Solution

• answer

I found the answer over here: https://intellij-support.jetbrains.com/hc/en-us/community/posts/115000004090-Updating-HTML-and-Resources-without-restarting-application-server-Tomcat-8-Thymeleaf-3-Sparkjava-?page=1#community_comment_360000203964

• Reason as Ulisses Silva pointed out: the Thymeleaf's implementation of the TemplateResolver has a "cacheable" attribute with "true" as default attribute.

• Solution

set the "cacheable" attribute to false as follows to your TemplateResolver definition:

<property name="cacheable" value="false" />

Answered By - zaozaoer