# Factory Path Preferences

Annotation processors can generate additional Java code or other files, and produce problem markers, based on Java 5 (JSR-175) annotations. The Annotation Processing preference pane permits configuration of preferences that apply to all processors in a project or workspace. The Factory Path preference pane specifies which processors are enabled and permits configuration of individual processors. Settings in the Factory Path preference pane will only have an effect if annotation processing is enabled in the Annotation Processing preference pane.

The pane displays a list of all the plugins and jar files that contain annotation processors that may be applied to the project. To add or remove jar files from the list, use the corresponding buttons. Jar files may be specified by absolute path using the Add External Jars... button, or by path relative to a classpath variable using the Add Variable... button. All installed plugins that extend the org.eclipse.jdt.apt.annotationProcessorFactory extension point are also displayed in the list.

To enable a particular plugin or jar file, select the corresponding checkbox within the list. Processors within plugins and jars that are not checked will not be executed. If more than one processor claims the same annotation, only first one on the list will be served that annotation. To reorder the list, use the Up and Down buttons.

The Advanced... button leads to the Advanced Factory Path Options dialog, which is used to view the individual processors within a plugin or jar file and to configure additional options. If a plugin or jar file on the factory path is known to contain processors but it does not show any contents in the Advanced Factory Path Options dialog, it may be missing the META-INF/services entry or plugin.xml entry that is required to declare the processors. More information about developing annotation processors is available in the Getting Started with APT topic.