Basic usage information

Out of the box SpringLoaded should be usable without extra configuration, it has sensible defaults. Trying it out is as simple as:

java -javaagent:<pathto>/springloaded.jar -noverify SomeJavaClass

What is the default behaviour?

Making a type reloadable is quite expensive so not everything the JVM loads goes through the process. When the JVM loads a type it can determine where the class was loaded from - this information is used to make a simple choice. If the class came from a .class file on disk, it is considered a piece of the application and made reloadable. If the class came from inside a zip/jar, it is considered a piece of the infrastructure and not made reloadable. Now, it is sometimes expensive to track down where types have been loaded from so the process for rejecting some infrastructure types is accelerated by considering just the name of the type. The following packages are considered 'infrastructure':

antlr/
org/springsource/loaded/
com/springsource/tcserver/
com/springsource/insight/
groovy/
groovyjarjarantlr/
groovyjarjarasm/
grails/
java/
javassist/
org/codehaus/groovy/
org/apache/
org/springframework/
org/hibernate/
org/hsqldb/
org/aspectj/
org/xml/
org/h2/

If you use one of these packages as your application package prefix, it will not be made reloadable at the moment. An aid in trying to diagnose when this is happening is the explain mode for springloaded, see Configuration Options for more information, but basically specifying this:

java -Dspringloaded=explain -javaagent:<pathto>/springloaded.jar -noverfy SomeJavaClass

will cause logging to come out explaining the decision process in springloaded:

Feb 05, 2014 11:00:51 AM org.springsource.loaded.TypeRegistry couldBeReloadable
INFO: WhyNotReloadable? The type org/apache/maven/model/building/ModelBuilder is using a package name 'org/apache/' which is considered
     infrastructure and types within it are not made reloadable