_ Git - ldk-java/blob - src/main/java/org/ldk/structs/ProbabilisticScorer.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 /**
  12  * [`Score`] implementation using channel success probability distributions.
  13  *
  14  * Based on *Optimally Reliable & Cheap Payment Flows on the Lightning Network* by Rene Pickhardt
  15  * and Stefan Richter [[1]]. Given the uncertainty of channel liquidity balances, probability
  16  * distributions are defined based on knowledge learned from successful and unsuccessful attempts.
  17  * Then the negative `log10` of the success probability is used to determine the cost of routing a
  18  * specific HTLC amount through a channel.
  19  *
  20  * Knowledge about channel liquidity balances takes the form of upper and lower bounds on the
  21  * possible liquidity. Certainty of the bounds is decreased over time using a decay function. See
  22  * [`ProbabilisticScoringParameters`] for details.
  23  *
  24  * Since the scorer aims to learn the current channel liquidity balances, it works best for nodes
  25  * with high payment volume or that actively probe the [`NetworkGraph`]. Nodes with low payment
  26  * volume are more likely to experience failed payment paths, which would need to be retried.
  27  *
  28  * # Note
  29  *
  30  * Mixing the `no-std` feature between serialization and deserialization results in undefined
  31  * behavior.
  32  *
  33  * [1]: https://arxiv.org/abs/2107.05322
  34  */
  35 @SuppressWarnings("unchecked") // We correctly assign various generic arrays
  36 public class ProbabilisticScorer extends CommonBase {
  37         ProbabilisticScorer(Object _dummy, long ptr) { super(ptr); }
  38         @Override @SuppressWarnings("deprecation")
  39         protected void finalize() throws Throwable {
  40                 super.finalize();
  41                 if (ptr != 0) { bindings.ProbabilisticScorer_free(ptr); }
  42         }
  43
  44         /**
  45          * Creates a new scorer using the given scoring parameters for sending payments from a node
  46          * through a network graph.
  47          */
  48         public static ProbabilisticScorer of(ProbabilisticScoringParameters params, NetworkGraph network_graph, Logger logger) {
  49                 long ret = bindings.ProbabilisticScorer_new(params == null ? 0 : params.ptr & ~1, network_graph == null ? 0 : network_graph.ptr & ~1, logger == null ? 0 : logger.ptr);
  50                 Reference.reachabilityFence(params);
  51                 Reference.reachabilityFence(network_graph);
  52                 Reference.reachabilityFence(logger);
  53                 if (ret >= 0 && ret <= 4096) { return null; }
  54                 org.ldk.structs.ProbabilisticScorer ret_hu_conv = null; if (ret < 0 || ret > 4096) { ret_hu_conv = new org.ldk.structs.ProbabilisticScorer(null, ret); }
  55                 ret_hu_conv.ptrs_to.add(ret_hu_conv);
  56                 ret_hu_conv.ptrs_to.add(network_graph);
  57                 ret_hu_conv.ptrs_to.add(logger);
  58                 return ret_hu_conv;
  59         }
  60
  61         /**
  62          * Dump the contents of this scorer into the configured logger.
  63          *
  64          * Note that this writes roughly one line per channel for which we have a liquidity estimate,
  65          * which may be a substantial amount of log output.
  66          */
  67         public void debug_log_liquidity_stats() {
  68                 bindings.ProbabilisticScorer_debug_log_liquidity_stats(this.ptr);
  69                 Reference.reachabilityFence(this);
  70         }
  71
  72         /**
  73          * Constructs a new Score which calls the relevant methods on this_arg.
  74          * This copies the `inner` pointer in this_arg and thus the returned Score must be freed before this_arg is
  75          */
  76         public Score as_Score() {
  77                 long ret = bindings.ProbabilisticScorer_as_Score(this.ptr);
  78                 Reference.reachabilityFence(this);
  79                 if (ret >= 0 && ret <= 4096) { return null; }
  80                 Score ret_hu_conv = new Score(null, ret);
  81                 ret_hu_conv.ptrs_to.add(this);
  82                 return ret_hu_conv;
  83         }
  84
  85         /**
  86          * Serialize the ProbabilisticScorer object into a byte array which can be read by ProbabilisticScorer_read
  87          */
  88         public byte[] write() {
  89                 byte[] ret = bindings.ProbabilisticScorer_write(this.ptr);
  90                 Reference.reachabilityFence(this);
  91                 return ret;
  92         }
  93
  94         /**
  95          * Read a ProbabilisticScorer from a byte array, created by ProbabilisticScorer_write
  96          */
  97         public static Result_ProbabilisticScorerDecodeErrorZ read(byte[] ser, ProbabilisticScoringParameters arg_a, NetworkGraph arg_b, Logger arg_c) {
  98                 long ret = bindings.ProbabilisticScorer_read(ser, arg_a == null ? 0 : arg_a.ptr & ~1, arg_b == null ? 0 : arg_b.ptr & ~1, arg_c == null ? 0 : arg_c.ptr);
  99                 Reference.reachabilityFence(ser);
 100                 Reference.reachabilityFence(arg_a);
 101                 Reference.reachabilityFence(arg_b);
 102                 Reference.reachabilityFence(arg_c);
 103                 if (ret >= 0 && ret <= 4096) { return null; }
 104                 Result_ProbabilisticScorerDecodeErrorZ ret_hu_conv = Result_ProbabilisticScorerDecodeErrorZ.constr_from_ptr(ret);
 105                 ret_hu_conv.ptrs_to.add(arg_b);
 106                 ret_hu_conv.ptrs_to.add(arg_c);
 107                 return ret_hu_conv;
 108         }
 109
 110 }