return list != null ? Collections.unmodifiableList(list) : Collections.emptyList();
    }

    private static Map<String, String> unmodifiable(Map<String, String> map) {
        return map != null ? Collections.unmodifiableMap(map) : Collections.emptyMap();
    }

    private static Map<String, String> toMap(Properties properties) {
        if (properties != null && !properties.isEmpty()) {

        final ComponentDef<?> componentDef = prototypeMap.get(name);
        if (componentDef != null) {
            return (T) componentDef.get();
        }
        final ComponentHolder<?> componentHolder = singletonMap.get(name);
        if (componentHolder != null) {
            return (T) componentHolder.get();
        }
        return null;
    }

    @Override
    public boolean available() {
        return available;

            }
        }
        return null;
    }

    protected Integer getAttributeAsInteger(final NamedNodeMap attributes, final String name) {
        final Node namedItem = attributes.getNamedItem(name);
        if (namedItem == null) {
            return null;
        }
        final String value = namedItem.getTextContent();
        if (value == null) {
            return null;
        }
        try {

    protected void assertObjectNotNull(String variableName, Object value) {
        if (variableName == null) {
            String msg = "The value should not be null: variableName=null value=" + value;
            throw new IllegalArgumentException(msg);
        }
        if (value == null) {
            String msg = "The value should not be null: variableName=" + variableName;
            throw new IllegalArgumentException(msg);
        }

    protected void assertObjectNotNull(String variableName, Object value) {
        if (variableName == null) {
            String msg = "The value should not be null: variableName=null value=" + value;
            throw new IllegalArgumentException(msg);
        }
        if (value == null) {
            String msg = "The value should not be null: variableName=" + variableName;
            throw new IllegalArgumentException(msg);
        }

                            valueClass == null ? null : valueClass.getName(), valueClass == null ? null : valueClass.getClassLoader(),
                            value, targetClass == null ? null : targetClass.getName(),
                            targetClass == null ? null : targetClass.getClassLoader()),
                    e);
        }
    }

    /**
     * インスタンスフィールドかどうか返します。

    if (localInputFuture == null | localExceptionType == null | localFallback == null
        // This check, unlike all the others, is a volatile read
        || isCancelled()) {
      return;
    }
    inputFuture = null;

    // For an explanation of the cases here, see the comments on AbstractTransformFuture.run.
    V sourceResult = null;
    Throwable throwable = null;
    try {

        doUpdate(entity, null);
    }

    public void insertOrUpdate(User entity) {
        doInsertOrUpdate(entity, null, null);
    }

    public void insertOrUpdate(User entity, RequestOptionCall<IndexRequestBuilder> opLambda) {
        entity.asDocMeta().indexOption(opLambda);
        doInsertOrUpdate(entity, null, null);
    }

    public void delete(User entity) {

     * @param model The model to wrap, may be {@code null}.
     */
    ModelData(Source source, Model model) {
        this.source = source;
        this.model = model;
    }

    /**
     * Creates a new container for the specified model.
     *
     * @param model The model to wrap, may be {@code null}.
     * @param groupId The effective group identifier of the model, may be {@code null}.

     * @param profile The (read-only) profile whose values should be injected, may be <code>null</code>.
     * @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}.
     */