The package javafx.beans.value contains the two fundamental interfaces javafx.beans.value.ObservableValue and javafx.beans.value.WritableValue and all of its sub-interfaces.

ObservableValue

An ObservableValue wraps a value that can be read and observed for invalidations and changes. Listeners have to implement either javafx.beans.InvalidationListener or javafx.beans.value.ChangeListener. To allow working with primitive types directly a number of sub-interfaces are defined.

Type	Sub-interface of ObservableValue
`boolean`	`javafx.beans.value.ObservableBooleanValue`
`double`	`javafx.beans.value.ObservableDoubleValue`
`float`	`javafx.beans.value.ObservableFloatValue`
`int`	`javafx.beans.value.ObservableIntegerValue`
`long`	`javafx.beans.value.ObservableLongValue`
`double`, `float`, `int`, `long`	`javafx.beans.value.ObservableNumberValue`
`Object`	`javafx.beans.value.ObservableObjectValue`
`String`	`javafx.beans.value.ObservableStringValue`

WritableValue

A WritableValue wraps a value that can be read and set. As with


	ObservableValues

, a number of sub-interfaces are defined to work with primitive types directly.

Type	Sub-interface of WritableValue
`boolean`	`javafx.beans.value.WritableBooleanValue`
`double`	`javafx.beans.value.WritableDoubleValue`
`float`	`javafx.beans.value.WritableFloatValue`
`int`	`javafx.beans.value.WritableIntegerValue`
`long`	`javafx.beans.value.WritableLongValue`
`double`, `float`, `int`, `long`	`javafx.beans.value.WritableNumberValue`
`Object`	`javafx.beans.value.WritableObjectValue`
`String`	`javafx.beans.value.WritableStringValue`