The AspectJ weaver applies aspects to Java classes. It can be used as a Java agent in order to apply load-time
weaving (LTW) during class-loading and also contains the AspectJ runtime classes.
The AspectJ runtime is a small library necessary to run Java programs enhanced by AspectJ aspects during a previous
compile-time or post-compile-time (binary weaving) build step.
AspectJ tools most notably contains the AspectJ compiler (AJC). AJC applies aspects to Java classes during
compilation, fully replacing Javac for plain Java classes and also compiling native AspectJ or annotation-based
@AspectJ syntax. Furthermore, AJC can weave aspects into existing class files in a post-compile binary weaving step.
This library is a superset of AspectJ weaver and hence also of AspectJ runtime.
AspectJ forks Eclipse Java Development Tools (JDT) Core, utilising the Eclipse Compiler (ECJ) + APT classes as the
foundation for the AspectJ Compiler (AJC).
The AspectJ matcher can be used for matching pointcuts independently of any AspectJ compilation or weaving steps.
Most notably, this can be used by frameworks such as Spring AOP which utilise the @AspectJ pointcut syntax but
implement aspect weaving in a way independent of AspectJ, e.g. using dynamic proxies.