@Nonnull
    @Override
    MessageBuilder append(char c);

    /**
     * Append content to the message buffer.
     *
     * @param value the content to append
     * @param offset the index of the first {@code char} to append
     * @param len the number of {@code char}s to append
     * @return the current builder
     */
    @Nonnull
    default MessageBuilder a(char[] value, int offset, int len) {

     * method provides an atomic compare-and-update of some key's value.
     *
     * @param key the key under which to store the session data, must not be {@code null}
     * @param oldValue the expected data currently associated with the key, may be {@code null}
     * @param newValue the data to associate with the key, may be {@code null} to remove the mapping

     *
     * @param message The detail message, may be {@code null}.
     * @param groupId The group id of the unresolvable model, may be {@code null}.
     * @param artifactId The artifact id of the unresolvable model, may be {@code null}.
     * @param version The version of the unresolvable model, may be {@code null}.
     * @param cause The cause, may be {@code null}.
     */

     * file and has not been subjected to inheritance, interpolation or profile/default injection.
     *
     * @param model The model to validate, must not be {@code null}.
     * @param request The model building request that holds further settings, must not be {@code null}.
     * @param problems The container used to collect problems that were encountered, must not be {@code null}.
     */

     * Resolves the runtime dependencies of the specified plugin.
     *
     * @param plugin The plugin for which to resolve the dependencies, must not be {@code null}.
     * @param pluginArtifact The plugin's main artifact, may be {@code null}.
     * @param dependencyFilter A filter to exclude artifacts from resolution (but not collection), may be {@code null}.

    public LookupException(String message) {
        super(message);
    }

    /**
     * @param message the message to give
     * @param e the {@link Exception}
     */
    public LookupException(String message, Exception e) {
        super(message, e);
    }

    /**
     * @param e the {@link Exception}
     */
    public LookupException(Exception e) {
        super(e);
    }

    /**
     * @param property the property to check
     * @return <code>true</code> if this is a valid property for this processor
     */
    boolean isValidProperty(String property);

    /**
     * This method is responsible for examining the request and possibly overwrite of the valid properties in the model
     *
     * @param modelProperties
     * @param request
     */

    @Nonnull
    Collection<ChecksumAlgorithm> select(@Nonnull Collection<String> algorithmNames);

    /**
     * Calculates checksums for specified data.
     *
     * @param data        The content for which to calculate checksums, must not be {@code null}.
     * @param algorithms  The checksum algorithms to use, must not be {@code null}.
     * @return The calculated checksums, indexed by algorithms, never {@code null}.

 */
public interface MavenArtifactRelocationSource {
    /**
     * Returns {@link Artifact} instance where to relocate to, or {@code null}.
     *
     * @param session The session, never {@code null}.
     * @param result The artifact descriptor result, never {@code null}.
     * @param model The artifact model, never {@code null}.
     * @return The {@link Artifact} to relocate to, or {@code null} if no relocation wanted.
     */

 * but at Maven runtime it MAY actually use that service.
 *
 * @since 4.0.0
 */
public interface ModelVersionParser {

    /**
     * Parses the specified version string, for example "1.0".
     *
     * @param version the version string to parse, must not be {@code null}
     * @return the parsed version, never {@code null}
     * @throws VersionParserException if the string violates the syntax rules of this scheme
     */
    @Nonnull