Arquivos dentro do web-inf/classes sao scaneados a procura de mudanças
fonte: http://edocs.bea.com/wls/docs70/webapp/deployment.html#143807
Hot-DeploymentRedeploy files in the WEB-INF/classes directory in the following way. If a class is deployed in WEB-INF/classes, then simply copying a new version of the file with a later time stamp will cause the Web Application to reload everything in the WEB-INF/classes folder with a new classloader.
The frequency in which WLS will look at the filesystem is governed through the console. In the Deployments–>Web Applications tab, select your Web Application. Go to the Configuration tab, and Files subtab, and enter a value in seconds for the Reload Period.