Example of InterledgerException

InterledgerException.java

package org.interledger.ilp.exceptions;

import java.time.ZonedDateTime;
import java.util.Collections;
import java.util.List;
import java.util.Objects;
import java.util.stream.Collectors;
import org.interledger.ilp.InterledgerAddress;
import org.interledger.ilp.InterledgerAddressBuilder;

/**
 * Base ILP exception.
 *
 * RFC REF: https://github.com/interledger/rfcs/blob/master/0003-interledger-protocol/0003-interledger-protocol.md
 */
public class InterledgerException extends RuntimeException {

  private static final long serialVersionUID = 1L;

  private final ErrorCode errorCode;
  private final InterledgerAddress triggeredBy;
  private final List<InterledgerAddress> forwardedBy;
  private final ZonedDateTime triggeredAt;

  /**
   * <p>Minimal-args Constructor.</p>
   *
   * <p>Allows a caller to construct an instance of this class with the minimal amount of supplied
   * information.</p>
   *
   * @param errorCode An instance of {@link ErrorCode}.
   * @param triggeredBy An instance of {@link InterledgerAddress} for the entity that originally
   * emitted the error (MAY be an address prefix if the entity that originally omitted the error is
   * a ledger).
   */
  public InterledgerException(
      final ErrorCode errorCode,
      final InterledgerAddress triggeredBy
  ) {
    this.errorCode = Objects.requireNonNull(errorCode);
    this.triggeredBy = Objects.requireNonNull(triggeredBy);
    this.triggeredAt = ZonedDateTime.now();
    this.forwardedBy = Collections.EMPTY_LIST; // immutable
  }

  /**
   * <p>All-args Constructor.</p>
   *
   * <p>Allows a caller to construct an instance of this class by specifying all required
   * fields.</p>
   *
   * @param errorCode An instance of {@link ErrorCode}.
   * @param triggeredBy An instance of {@link InterledgerAddress} for the entity that originally
   * emitted the error (MAY be an address prefix if the entity that originally omitted the error is
   * a ledger).
   * @param triggeredAt A {@link ZonedDateTime} indicating when the error was initially emitted.
   * @param forwardedBy A {@link List} of type {@link InterledgerAddress} that contains the
   */
  public InterledgerException(
      final ErrorCode errorCode,
      final InterledgerAddress triggeredBy,
      final ZonedDateTime triggeredAt,
      final List<InterledgerAddress> forwardedBy
  ) {
    this.errorCode = Objects.requireNonNull(errorCode);
    this.triggeredBy = Objects.requireNonNull(triggeredBy);
    this.triggeredAt = Objects.requireNonNull(triggeredAt);

    // Deep-copy the incoming list to normalize the InternetAddress, and then make it immutable.
    final List<InterledgerAddress> newList = deepCopyAndNormalize(forwardedBy);
    this.forwardedBy = Collections.unmodifiableList(newList);
  }

  /**
   * <p>All-args Constructor.</p>
   *
   * <p>Allows a caller to construct an instance of this class by specifying all required
   * fields.</p>
   *
   * @param errorCode An instance of {@link ErrorCode}.
   * @param triggeredBy An instance of {@link InterledgerAddress} for the entity that originally
   * emitted the error (MAY be an address prefix if the entity that originally omitted the error is
   * a ledger).
   * @param triggeredAt A {@link ZonedDateTime} indicating when the error was initially emitted.
   * @param forwardedBy A {@link List} of type {@link InterledgerAddress} that contains the
   * addresses of ILP connectors that relayed the error message.
   * @param data A {@link String} containing error data for debugging purposes.
   * @param cause An instance of {@link Throwable} that caused this exception.  Used for debugging.
   */
  public InterledgerException(
      final ErrorCode errorCode,
      final InterledgerAddress triggeredBy,
      final ZonedDateTime triggeredAt,
      final List<InterledgerAddress> forwardedBy,
      final String data,
      final Throwable cause
  ) {
    super(data, cause);
    this.errorCode = Objects.requireNonNull(errorCode);
    this.triggeredBy = Objects.requireNonNull(triggeredBy);
    this.triggeredAt = Objects.requireNonNull(triggeredAt);

    // Deep-copy the incoming list to normalize the InternetAddress, and then make it immutable.
    final List<InterledgerAddress> newList = deepCopyAndNormalize(forwardedBy);
    this.forwardedBy = Collections.unmodifiableList(newList);
  }

  /**
   * Construct for adding an additional forwardedBy.
   *
   * @param interledgerException An instance of {@link InterledgerException}.
   * @param forwardedBy An instance of {@link InterledgerAddress} that contains an address to be
   * added to the list of forwarded -by addresses in the supplied {@code interledgerException}.
   */
  public InterledgerException(
      final InterledgerException interledgerException,
      final InterledgerAddress forwardedBy
  ) {
    super(interledgerException.getMessage(), interledgerException.getCause());

    this.errorCode = interledgerException.getErrorCode();
    this.triggeredBy = interledgerException.getTriggeredBy();
    this.triggeredAt = interledgerException.getTriggeredAt();

    // Deep-copy the incoming list to normalize the InternetAddress, and then make it immutable.
    final List<InterledgerAddress> newList = deepCopyAndNormalize(
        interledgerException.getForwardedBy());
    newList.add(forwardedBy);
    this.forwardedBy = Collections.unmodifiableList(newList);
  }

  /**
   * Deep-copy the {@link List} supplied by {@code addresses} and return a new list with normalized
   * instances of {@link InterledgerAddress}.
   */
  private List<InterledgerAddress> deepCopyAndNormalize(final List<InterledgerAddress> addresses) {
    return addresses.stream()
        .map(InterledgerAddressBuilder::new)
        .map(InterledgerAddressBuilder::build)
        .collect(Collectors.toList());
  }

  public ErrorCode getErrorCode() {
    return errorCode;
  }

  public InterledgerAddress getTriggeredBy() {
    return triggeredBy;
  }

  public List<InterledgerAddress> getForwardedBy() {
    return forwardedBy;
  }

  public ZonedDateTime getTriggeredAt() {
    return triggeredAt;
  }

  public enum ErrorCode {
    // FINAL ERRORS
    F00_BAD_REQUEST("F00", "BAD REQUEST"),
    F01_INVALID_PAQUET("F01", "INVALID PAQUET"),
    F02_UNREACHABLE("F02", "UNREACHABLE"),
    F03_INVALID_AMOUNT("F03", "INVALID AMOUNT"),
    F04_INSUFFICIENT_DST_AMOUNT("F04", "INSUFFICIENT DST. AMOUNT"),
    F05_WRONG_CONDITION("F05", "WRONG CONDITION"),
    F06_UNEXPECTED_PAYMENT("F06", "UNEXPECTED PAYMENT"),
    F07_CANNOT_RECEIVE("F07", "CANNOT RECEIVE"),
    F99_APPLICATION_ERROR("F99", "APPLICATION ERROR"),

    T00_INTERNAL_ERROR("T00", "INTERNAL ERROR"),
    T01_LEDGER_UNREACHABLE("T01", "LEDGER UNREACHABLE"),
    T02_LEDGER_BUSY("T02", "LEDGER BUSY"),
    T03_CONNECTOR_BUSY("T03", "CONNECTOR BUSY"),
    T04_INSUFFICIENT_LIQUIDITY("T04", "INSUFFICIENT LIQUIDITY"),
    T05_RATE_LIMITED("T05", "RATE LIMITED"),
    T99_APPLICATION_ERROR("T99", "APPLICATION ERROR"),

    R00_TRANSFER_TIMED_OUT("R00", "TRANSFER TIMED OUT"),
    R01_INSUFFICEINT_SOURCE_AMOUNT("R01", "INSUFFICEINT SOURCE AMOUNT"),
    R02_INSUFFICIENT_TIMEOUT("R02", "INSUFFICIENT TIMEOUT"),
    R99_APPLICATION_ERROR("R99", "APPLICATION ERROR");

    private final String code;
    private final String name;

    ErrorCode(String code, String name) {
      if (code == null || name == null) {
        throw new RuntimeException("code and/or name can not be null");
      }
      code = code.trim();
      name = name.trim();
      if (code.length() != 3) {
        throw new RuntimeException("error code length must be equal to 3");
      }
      char type = code.charAt(0);
      if (type != 'F' && type != 'T' && type != 'R') {
        throw new RuntimeException("error code must be := 'F' | 'T' | 'R'");
      }
      this.code = code;
      this.name = name;
    }

    @Override
    public String toString() {
      return this.code + "-" + this.name();
    }

  }

}