AspectJ
AspectJ is an aspect-oriented extension created at PARC for the Java programming language. It is available in Eclipse Foundation open-source projects, both stand-alone and integrated into Eclipse. AspectJ has become the widely used de facto standard for AOP by emphasizing simplicity and usability for end users. It uses Java-like syntax and has included IDE integrations for displaying crosscutting structure since its initial public release in 2001.
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