Package ch.bailu.gtk.gio

Class Initable

java.lang.Object
ch.bailu.gtk.type.Type
ch.bailu.gtk.type.Pointer
ch.bailu.gtk.gobject.Object
ch.bailu.gtk.type.Interface
ch.bailu.gtk.gio.Initable
All Implemented Interfaces:
PointerInterface
public class Initable extends Interface
#GInitable is implemented by objects that can fail during
initialization. If an object implements this interface then
it must be initialized as the first thing after construction,
either via g_initable_init() or g_async_initable_init_async()
(the latter is only available if it also implements #GAsyncInitable).

If the object is not initialized, or initialization returns with an
error, then all operations on the object except g_object_ref() and
g_object_unref() are considered to be invalid, and have undefined
behaviour. They will often fail with g_critical() or g_warning(), but
this must not be relied on.

Users of objects implementing this are not intended to use
the interface method directly, instead it will be used automatically
in various ways. For C applications you generally just call
g_initable_new() directly, or indirectly via a foo_thing_new() wrapper.
This will call g_initable_init() under the cover, returning %NULL and
setting a #GError on failure (at which point the instance is
unreferenced).

For bindings in languages where the native constructor supports
exceptions the binding could check for objects implementing %GInitable
during normal construction and automatically initialize them, throwing
an exception on failure.

https://docs.gtk.org/gio/iface.Initable.html

  • Constructor Details

  • Method Details

    • getClassHandler

      public static ClassHandler getClassHandler()

    • init

      public boolean init(@Nullable Cancellable cancellable) throws AllocationError
      Initializes the object implementing the interface.

      This method is intended for language bindings. If writing in C,
      g_initable_new() should typically be used instead.

      The object must be initialized before any real use after initial
      construction, either with this function or g_async_initable_init_async().

      Implementations may also support cancellation. If @cancellable is not %NULL,
      then initialization can be cancelled by triggering the cancellable object
      from another thread. If the operation was cancelled, the error
      %G_IO_ERROR_CANCELLED will be returned. If @cancellable is not %NULL and
      the object doesn't support cancellable initialization the error
      %G_IO_ERROR_NOT_SUPPORTED will be returned.

      If the object is not initialized, or initialization returns with an
      error, then all operations on the object except g_object_ref() and
      g_object_unref() are considered to be invalid, and have undefined
      behaviour. See the [introduction][ginitable] for more details.

      Callers should not assume that a class which implements #GInitable can be
      initialized multiple times, unless the class explicitly documents itself as
      supporting this. Generally, a class’ implementation of init() can assume
      (and assert) that it will only be called once. Previously, this documentation
      recommended all #GInitable implementations should be idempotent; that
      recommendation was relaxed in GLib 2.54.

      If a class explicitly supports being initialized multiple times, it is
      recommended that the method is idempotent: multiple calls with the same
      arguments should return the same results. Only the first call initializes
      the object; further calls return the result of the first call.

      One reason why a class might need to support idempotent initialization is if
      it is designed to be used via the singleton pattern, with a
      #GObjectClass.constructor that sometimes returns an existing instance.
      In this pattern, a caller would expect to be able to call g_initable_init()
      on the result of g_object_new(), regardless of whether it is in fact a new
      instance.
      Parameters:
      cancellable - optional #GCancellable object, %NULL to ignore.
      Returns:
      %TRUE if successful. If an error has occurred, this function will return %FALSE and set @error appropriately if present.
      Throws:
      AllocationError

    • getTypeID

      public static long getTypeID()

    • getParentTypeID

      public static long getParentTypeID()

    • getTypeSize

      public static TypeSystem.TypeSize getTypeSize()

    • getParentTypeSize

      public static TypeSystem.TypeSize getParentTypeSize()

    • getInstanceSize

      public static int getInstanceSize()