gradle/org.gradle.api.plugins/ExtraPropertiesExtension

ExtraPropertiesExtension

interface ExtraPropertiesExtension(source)

Additional, ad-hoc, properties for Gradle domain objects.

Extra properties extensions allow new properties to be added to existing domain objects. They act like maps, allowing the storage of arbitrary key/value pairs. All ExtensionAware Gradle domain objects intrinsically have an extension named "{@value #EXTENSION_NAME}" of this type.

An important feature of extra properties extensions is that all of its properties are exposed for reading and writing via the ExtensionAware object that owns the extension.

project.ext.set("myProp", "myValue")
assert project.myProp == "myValue"

project.myProp = "anotherValue"
assert project.myProp == "anotherValue"
assert project.ext.get("myProp") == "anotherValue"

Extra properties extension objects support Groovy property syntax. That is, a property can be read via extension.«name» and set via extension.«name» = "value". Wherever possible, the Groovy property syntax should be preferred over the get and set methods.

project.ext {
  myprop = "a"
}
assert project.myprop == "a"
assert project.ext.myprop == "a"

project.myprop = "b"
assert project.myprop == "b"
assert project.ext.myprop == "b"

You can also use the Groovy accessor syntax to get and set properties on an extra properties extension.

project.ext["otherProp"] = "a"
assert project.otherProp == "a"
assert project.ext["otherProp"] == "a"

The exception that is thrown when an attempt is made to get the value of a property that does not exist is different depending on whether the Groovy syntax is used or not. If Groovy property syntax is used, the Groovy groovy.lang.MissingPropertyException will be thrown. When the get method is used, an UnknownPropertyException will be thrown.