package org.ldk.structs;
import org.ldk.impl.bindings;
-
import org.ldk.enums.*;
+import org.ldk.util.*;
+import java.util.Arrays;
+/**
+ * The `Filter` trait defines behavior for indicating chain activity of interest pertaining to
+ * channels.
+ *
+ * This is useful in order to have a [`Watch`] implementation convey to a chain source which
+ * transactions to be notified of. Notification may take the form of pre-filtering blocks or, in
+ * the case of [BIP 157]/[BIP 158], only fetching a block if the compact filter matches. If
+ * receiving full blocks from a chain source, any further filtering is unnecessary.
+ *
+ * After an output has been registered, subsequent block retrievals from the chain source must not
+ * exclude any transactions matching the new criteria nor any in-block descendants of such
+ * transactions.
+ *
+ * Note that use as part of a [`Watch`] implementation involves reentrancy. Therefore, the `Filter`
+ * should not block on I/O. Implementations should instead queue the newly monitored data to be
+ * processed later. Then, in order to block until the data has been processed, any [`Watch`]
+ * invocation that has called the `Filter` must return [`TemporaryFailure`].
+ *
+ * [`TemporaryFailure`]: channelmonitor::ChannelMonitorUpdateErr::TemporaryFailure
+ * [BIP 157]: https://github.com/bitcoin/bips/blob/master/bip-0157.mediawiki
+ * [BIP 158]: https://github.com/bitcoin/bips/blob/master/bip-0158.mediawiki
+ */
+@SuppressWarnings("unchecked") // We correctly assign various generic arrays
public class Filter extends CommonBase {
- Filter(Object _dummy, long ptr) { super(ptr); }
- public Filter(bindings.LDKFilter arg) {
+ final bindings.LDKFilter bindings_instance;
+ Filter(Object _dummy, long ptr) { super(ptr); bindings_instance = null; }
+ private Filter(bindings.LDKFilter arg) {
super(bindings.LDKFilter_new(arg));
this.ptrs_to.add(arg);
+ this.bindings_instance = arg;
}
@Override @SuppressWarnings("deprecation")
protected void finalize() throws Throwable {
- bindings.Filter_free(ptr); super.finalize();
+ if (ptr != 0) { bindings.Filter_free(ptr); } super.finalize();
}
+ public static interface FilterInterface {
+ /**
+ * Registers interest in a transaction with `txid` and having an output with `script_pubkey` as
+ * a spending condition.
+ */
+ void register_tx(byte[] txid, byte[] script_pubkey);
+ /**
+ * Registers interest in spends of a transaction output identified by `outpoint` having
+ * `script_pubkey` as the spending condition.
+ */
+ void register_output(OutPoint outpoint, byte[] script_pubkey);
+ }
+ private static class LDKFilterHolder { Filter held; }
+ public static Filter new_impl(FilterInterface arg) {
+ final LDKFilterHolder impl_holder = new LDKFilterHolder();
+ impl_holder.held = new Filter(new bindings.LDKFilter() {
+ @Override public void register_tx(byte[] txid, byte[] script_pubkey) {
+ arg.register_tx(txid, script_pubkey);
+ }
+ @Override public void register_output(long outpoint, byte[] script_pubkey) {
+ OutPoint outpoint_hu_conv = new OutPoint(null, outpoint);
+ arg.register_output(outpoint_hu_conv, script_pubkey);
+ }
+ });
+ return impl_holder.held;
+ }
+ /**
+ * Registers interest in a transaction with `txid` and having an output with `script_pubkey` as
+ * a spending condition.
+ */
public void register_tx(byte[] txid, byte[] script_pubkey) {
bindings.Filter_register_tx(this.ptr, txid, script_pubkey);
}
+ /**
+ * Registers interest in spends of a transaction output identified by `outpoint` having
+ * `script_pubkey` as the spending condition.
+ */
public void register_output(OutPoint outpoint, byte[] script_pubkey) {
bindings.Filter_register_output(this.ptr, outpoint == null ? 0 : outpoint.ptr & ~1, script_pubkey);
this.ptrs_to.add(outpoint);