_ Git - ldk-java/blob - src/main/java/org/ldk/structs/EventsProvider.java

   1 package org.ldk.structs;
   2
   3 import org.ldk.impl.bindings;
   4 import org.ldk.enums.*;
   5 import org.ldk.util.*;
   6 import java.util.Arrays;
   7 import java.lang.ref.Reference;
   8 import javax.annotation.Nullable;
   9
  10 /**
  11  * A trait indicating an object may generate events.
  12  *
  13  * Events are processed by passing an [`EventHandler`] to [`process_pending_events`].
  14  *
  15  * Implementations of this trait may also feature an async version of event handling, as shown with
  16  * [`ChannelManager::process_pending_events_async`] and
  17  * [`ChainMonitor::process_pending_events_async`].
  18  *
  19  * # Requirements
  20  *
  21  * When using this trait, [`process_pending_events`] will call [`handle_event`] for each pending
  22  * event since the last invocation.
  23  *
  24  * In order to ensure no [`Event`]s are lost, implementors of this trait will persist [`Event`]s
  25  * and replay any unhandled events on startup. An [`Event`] is considered handled when
  26  * [`process_pending_events`] returns, thus handlers MUST fully handle [`Event`]s and persist any
  27  * relevant changes to disk *before* returning.
  28  *
  29  * Further, because an application may crash between an [`Event`] being handled and the
  30  * implementor of this trait being re-serialized, [`Event`] handling must be idempotent - in
  31  * effect, [`Event`]s may be replayed.
  32  *
  33  * Note, handlers may call back into the provider and thus deadlocking must be avoided. Be sure to
  34  * consult the provider's documentation on the implication of processing events and how a handler
  35  * may safely use the provider (e.g., see [`ChannelManager::process_pending_events`] and
  36  * [`ChainMonitor::process_pending_events`]).
  37  *
  38  * (C-not implementable) As there is likely no reason for a user to implement this trait on their
  39  * own type(s).
  40  *
  41  * [`process_pending_events`]: Self::process_pending_events
  42  * [`handle_event`]: EventHandler::handle_event
  43  * [`ChannelManager::process_pending_events`]: crate::ln::channelmanager::ChannelManager#method.process_pending_events
  44  * [`ChainMonitor::process_pending_events`]: crate::chain::chainmonitor::ChainMonitor#method.process_pending_events
  45  * [`ChannelManager::process_pending_events_async`]: crate::ln::channelmanager::ChannelManager::process_pending_events_async
  46  * [`ChainMonitor::process_pending_events_async`]: crate::chain::chainmonitor::ChainMonitor::process_pending_events_async
  47  */
  48 @SuppressWarnings("unchecked") // We correctly assign various generic arrays
  49 public class EventsProvider extends CommonBase {
  50         final bindings.LDKEventsProvider bindings_instance;
  51         EventsProvider(Object _dummy, long ptr) { super(ptr); bindings_instance = null; }
  52         private EventsProvider(bindings.LDKEventsProvider arg) {
  53                 super(bindings.LDKEventsProvider_new(arg));
  54                 this.ptrs_to.add(arg);
  55                 this.bindings_instance = arg;
  56         }
  57         @Override @SuppressWarnings("deprecation")
  58         protected void finalize() throws Throwable {
  59                 if (ptr != 0) { bindings.EventsProvider_free(ptr); } super.finalize();
  60         }
  61         /**
  62          * Destroys the object, freeing associated resources. After this call, any access
  63          * to this object may result in a SEGFAULT or worse.
  64          *
  65          * You should generally NEVER call this method. You should let the garbage collector
  66          * do this for you when it finalizes objects. However, it may be useful for types
  67          * which represent locks and should be closed immediately to avoid holding locks
  68          * until the GC runs.
  69          */
  70         public void destroy() {
  71                 if (ptr != 0) { bindings.EventsProvider_free(ptr); }
  72                 ptr = 0;
  73         }
  74         public static interface EventsProviderInterface {
  75                 /**
  76                  * Processes any events generated since the last call using the given event handler.
  77                  *
  78                  * See the trait-level documentation for requirements.
  79                  */
  80                 void process_pending_events(EventHandler handler);
  81         }
  82         private static class LDKEventsProviderHolder { EventsProvider held; }
  83         public static EventsProvider new_impl(EventsProviderInterface arg) {
  84                 final LDKEventsProviderHolder impl_holder = new LDKEventsProviderHolder();
  85                 impl_holder.held = new EventsProvider(new bindings.LDKEventsProvider() {
  86                         @Override public void process_pending_events(long handler) {
  87                                 EventHandler ret_hu_conv = new EventHandler(null, handler);
  88                                 if (ret_hu_conv != null) { ret_hu_conv.ptrs_to.add(this); };
  89                                 arg.process_pending_events(ret_hu_conv);
  90                                 Reference.reachabilityFence(arg);
  91                         }
  92                 });
  93                 return impl_holder.held;
  94         }
  95         /**
  96          * Processes any events generated since the last call using the given event handler.
  97          *
  98          * See the trait-level documentation for requirements.
  99          */
 100         public void process_pending_events(org.ldk.structs.EventHandler handler) {
 101                 bindings.EventsProvider_process_pending_events(this.ptr, handler.ptr);
 102                 Reference.reachabilityFence(this);
 103                 Reference.reachabilityFence(handler);
 104                 if (this != null) { this.ptrs_to.add(handler); };
 105         }
 106
 107 }