* @param source The source of the problem, may be {@code null}.
     * @param lineNumber The one-based index of the line containing the error or {@code -1} if unknown.
     * @param columnNumber The one-based index of the column containing the error or {@code -1} if unknown.
     * @param exception The exception that caused this problem, may be {@code null}.
     */
    // mkleint: does this need to be public?
    public DefaultModelProblem(

        expect:
        repository.find('unknown') == null
    }

    def getFailsForUnknownClass() {
        given:
        repository.put('unkown', new TestDomainObject('unknown'))

        when:
        repository.get('unknown')

        then:
        UnknownDomainObjectException e = thrown()
        e.message == 'No meta-data is available for class \'unknown\'. Did you mean? [unkown]'
    }

     */
    String getSource();

    /**
     * Gets the one-based index of the line containing the problem. The line number should refer to some text file that
     * is given by {@link #getSource()}.
     *
     * @return The one-based index of the line containing the problem or a non-positive value if unknown.
     */
    int getLineNumber();

    /**

     *
     * @param message The error message, may be {@code null}.
     * @param lineNumber The one-based index of the line containing the error or {@code -1} if unknown.
     * @param columnNumber The one-based index of the column containing the error or {@code -1} if unknown.
     */
    public MetadataParseException(String message, int lineNumber, int columnNumber) {
        super(message);
        this.lineNumber = lineNumber;

     */
    public String getId() {
        return (getGroupId() == null ? "[unknown-group-id]" : getGroupId())
            + ":" + (getArtifactId() == null ? "[unknown-artifact-id]" : getArtifactId())
            + ":" + (getVersion() == null ? "[unknown-version]" : getVersion());
    }
            ]]>
          </code>
        </codeSegment>
      </codeSegments>
    </class>

     */
    String getSource();

    /**
     * Gets the one-based index of the line containing the problem. The line number should refer to some text file that
     * is given by {@link #getSource()}.
     *
     * @return The one-based index of the line containing the problem or a non-positive value if unknown.
     */
    int getLineNumber();

    /**

        when(session.getRequest()).thenReturn(executionRequest);
        Session sessionv4 = mock(Session.class);
        when(session.getSession()).thenReturn(sessionv4);
        when(sessionv4.getToolchains()).thenReturn(toolchainModels);

        List<Toolchain> toolchains = toolchainManager.getToolchains(session, "unknown", null);

		return i, Number, err
	case '-':
		if c = d.next(); c < '0' || c > '9' {
			return nil, Unknown, d.mkError(ErrSyntax, "in negative numeric literal")
		}
		n, err := d.number()
		if err != nil {
			return nil, Unknown, err
		}
		return -n, Number, nil
	case 'f':
		if d.remaining() < 4 {
			return nil, Unknown, d.mkError(ErrUnexpectedEOF)
		}
		//nolint:gocritic

    /**
     * Gets the identifier of the project that could not be built. The general format of the identifier is {@code
     * <groupId>:<artifactId>:<version>} but some of these coordinates may still be unknown at the point the exception
     * is thrown so this information is merely meant to assist the user.
     *
     * @return The identifier of the project or an empty string if not known, never {@code null}.
     */

		return payload, 0, 0, fmt.Errorf("xlMeta: unknown XLv2 header, expected %v, got %v", xlHeader[:4], buf[:4])
	}

	if bytes.Equal(buf[4:8], []byte("1   ")) {
		// Set as 1,0.
		major, minor = 1, 0
	} else {
		major, minor = binary.LittleEndian.Uint16(buf[4:6]), binary.LittleEndian.Uint16(buf[6:8])
	}
	if major > xlVersionMajor {
		return buf[8:], major, minor, fmt.Errorf("xlMeta: unknown major version %d found", major)
	}