Is there a way to deploy a jar without restarting in Tomcat 9?

Question

I know this question has came up before here, however this is in regards to tomcat 9.

Is there anything that has changed in latest tomcat releases that allows to deploy a jar file without restarting tomcat ? We have been using tomcat 7 in our development and all developers restarting tomcat has been time consuming. Its application that has 700 java files that gets built in to a .jar file and about 1000 jsp files that rely on those .jar file, we are not using war. Can WatchedResource be used for this ?

Have you considered [JRebel](http://stackoverflow.com/questions/37393783/tomcat-hot-depolyment-for-new-class-files)? — paulsm4, Apr 01 '17 at 18:26
I am not an expert Tomcat user; but why don't you deploy a WAR; which can by nature be re-loaded without restarting tomcat? — GhostCat, Apr 01 '17 at 18:33

score 1 · Answer 1 · answered Apr 01 '17 at 18:27

1

You can always restart your webapp and not your Tomcat instance as long as the JAR resides in WEB-INF/lib and not in CATALINA_BASE/lib.

answered Apr 01 '17 at 18:27

Michael-O

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I am not using war deploy , they are plain jsps and jars , so that wont work right ? – Pit Digger Apr 01 '17 at 23:17
Same approach, you have an exploded app. Hit reload in Tomcat manager or via JMX. – Michael-O Apr 01 '17 at 23:27

score 1 · Answer 2 · answered Apr 01 '17 at 18:36

If you are using Eclipse IDE, then you can simply use FileSync plugin to hot deploy the .class files into tomcat WEB-INF/classes folder.

Basically, you need to map YOUR_PROJECT/target/classes folder to WEB-INF/classes so that they will always be in sync.

This is what we do in our project to avoid the restarts of Tomcat because of source file changes.

Is there a way to deploy a jar without restarting in Tomcat 9?

2 Answers2