}

        public PluginDependencySpec id(String id, int requestLineNumber) {
            PluginDependencySpecImpl spec = new PluginDependencySpecImpl(id, requestLineNumber);
            specs.add(spec);
            return spec;
        }
    }

    private static class PluginDependencySpecImpl implements PluginDependencySpec {
        private final PluginId id;
        private String version;

        @Override
        public PluginDependencySpec id(String id) {
            return new PluginDependencySpecImpl(DefaultPluginId.of(id));
        }
    }

    private class PluginDependencySpecImpl implements PluginDependencySpec {
        private final PluginId id;

        private PluginDependencySpecImpl(PluginId id) {
            this.id = id;
        }

        @Override