Package io.github.jwharm.javagi.gobject

Class JavaClosure

java.lang.Object

io.github.jwharm.javagi.base.ProxyInstance

org.gnome.gobject.Closure

io.github.jwharm.javagi.gobject.JavaClosure

All Implemented Interfaces:

Proxy

public class JavaClosure
extends Closure

An implementation of Closure that can be used with Java callbacks. In most cases, the callback will be invoked using reflection. For two common cases (Runnable and BooleanSupplier), the callback will be invoked directly.

Nested Class Summary

Nested classes/interfaces inherited from class org.gnome.gobject.Closure

Closure.MarshalCallback

Constructor Summary

Constructors

Constructor	Description
JavaClosure(Object lambda)	Construct a Closure that will invoke the provided Java lambda using reflection.
JavaClosure(Object instance, Method method)	Construct a Closure that will invoke the provided Java method using reflection.
JavaClosure(Runnable callback)	Construct a Closure for a method or lambda that takes no parameters and returns void.
JavaClosure(BooleanSupplier callback)	Construct a Closure for a method or lambda that takes no parameters and returns boolean.

Method Summary

Modifier and Type	Method	Description
static Method	getSingleMethod(Class<?> cls)	Get the single abstract method (SAM) implementation of a class that implements a functional interface.

Methods inherited from class org.gnome.gobject.Closure

addFinalizeNotifier, addInvalidateNotifier, addMarshalGuards, getMemoryLayout, getType, invalidate, invoke, object, overrideMarshal, readData, readNotifiers, ref, removeFinalizeNotifier, removeInvalidateNotifier, setMarshal, setMetaMarshal, simple, sink, unref, writeData, writeNotifiers

Methods inherited from class io.github.jwharm.javagi.base.ProxyInstance

equals, handle, hashCode

Methods inherited from class java.lang.Object

clone, finalize, getClass, notify, notifyAll, toString, wait, wait, wait

Constructor Details

JavaClosure

public JavaClosure(Runnable callback)

Construct a Closure for a method or lambda that takes no parameters and returns void.

Parameters:

callback - a callback with signature void run()

JavaClosure

public JavaClosure(BooleanSupplier callback)

Construct a Closure for a method or lambda that takes no parameters and returns boolean.

Parameters:

callback - a callback with signature boolean run()

JavaClosure

public JavaClosure(Object lambda)
            throws IllegalArgumentException

Construct a Closure that will invoke the provided Java lambda using reflection. The Closure function arguments are read from the argument-Value containers and passed to the lambda. The return value of the lambda is put in the Closure return-Value.

Parameters:

lambda - a lambda (instance of a functional interface)

Throws:

IllegalArgumentException - if the lambda is not an instance of a functional interface

JavaClosure

public JavaClosure(Object instance,
 Method method)

Construct a Closure that will invoke the provided Java method using reflection. The Closure function arguments are read from the argument-Value containers and passed to the method. The return value of the method is put in the Closure return-Value.

Parameters:

instance - a class instance on which the provided method will be invoked. When the method is static, this parameter is ignored and and may be null.

method - the method to invoke. See Method.invoke(Object, Object...)

Method Details

getSingleMethod

public static Method getSingleMethod(Class<?> cls)
                              throws IllegalArgumentException

Get the single abstract method (SAM) implementation of a class that implements a functional interface. A functional interface is an interface with exactly one abstract method.

Parameters:

cls - a functional interface

Returns:

the Method reference to the method that implements the SAM

Throws:

IllegalArgumentException - if cls is not a functional interface