<>IDEA Lose focus , Cancel automatic compilation ( resolved )
  The project is deployed in the way of hot deployment , And then with Debug Mode start ( It is convenient for us to debug code in the process of project execution. ). Specific hot deployment methods , There are many tutorials on the Internet , Please visit Baidu by yourself . 
 But when we use Debug After the project is started in this way , We're writing Java When you code , Once the focus item is lost, an error will be reported , From a compilation point of view, this is a convenient function , After all, we can find the mistakes of our project in time , But from the perspective of user experience , Personally, I don't think it's that friendly . So I suggest that we cancel this function 
 Many hot deployment tutorials on the Internet let us set these two options to Update classes and resources
, They don't tell us what these two are , The key to change is here .
On Update action: When the code changes ,IDEA What to do 
 * 
Update resource: If there is an update , And the update resource is (xx.jsp,xx.xml, barring Java file ), It will take effect immediately 
 * 
Update classes and 
resources: If there is an update , And the update resource is ( Resource file or Java file ), It will take effect immediately . In normal operation mode , modify Java The document will not take effect immediately ;
 But in Debug Mode , It will take effect immediately . In both modes , modify resource Resource files are available immediately .
 * 
Redploy: Redeploy project , Put the original war package ( Our project is based on war The form of the package is placed in the Tomcat On the server ) Redeployment 
 * 
Restart: Restart the server ( The longest time , Not recommended )
On Frame deactivation: When you lose focus ( Don't stop at IDEA inside ),IDEA What to do 
 * 
Do nothing: Don't do anything ( Recommended )
 * 
Update resource: If there is an update , And the update resource is (xx.jsp,xx.xml, barring Java file ), It will take effect immediately 
 * 
Update classes and 
resource: If there is an update , And the update resource is ( Resource file or Java file ), It will take effect immediately . In normal operation mode , modify Java The document will not take effect immediately ;
 But in Debug Mode , It will take effect immediately . In both modes , modify resource Resource files are available immediately .
 So we just need to On Frame deactivation, Amend to read Do nothing that will do 
 Set to Do 
nothing after , Our project will not compile automatically ( On the basis of the fact that we have not set up automatic compilation ). However, I prefer manual compilation , After all, it's just a matter of ordering , How much computer performance will it cost to turn on automatic compilation . How to turn on automatic compilation , Please Baidu yourself .
Debug In the case of starting the project , You can click the little beetle icon to update the resources we want .
  But I found different versions IDEA The click effect of this little beetle icon is different , Specific operation according to your requirements IDEA Look again 
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