org.gradle.api.plugins
Interfaces 
Convention
ObjectConfigurationAction
PluginCollection
PluginContainer
Classes 
BasePlugin
BasePluginConvention
GroovyBasePlugin
GroovyPlugin
JavaBasePlugin
JavaPlugin
JavaPluginConvention
MavenPlugin
MavenPluginConvention
ProjectReportsPlugin
ProjectReportsPluginConvention
ReportingBasePlugin
ReportingBasePluginConvention
WarPlugin
WarPluginConvention
Exceptions 
PluginInstantiationException
UnknownPluginException