org.gradle.api
Interfaces 
Action
DomainObjectCollection
DomainObjectContainer
Plugin
Project
ProjectAction
ProjectEvaluationListener
Rule
Task
TaskAction
Transformer
Classes 
AntBuilder
Enums 
JavaVersion
PathValidation
Exceptions 
CircularReferenceException
GradleException
GradleScriptException
IllegalDependencyNotation
IllegalOperationAtExecutionTimeException
InvalidUserDataException
UncheckedIOException
UnknownDomainObjectException
UnknownProjectException
UnknownTaskException