Java Code Examples for com.tinkerpop.blueprints.Element#removeProperty()

/**
 * For those graphs that do no support automatic reindexing of elements when a key is provided for indexing, this method can be used to simulate that behavior.
 * The elements in the graph are iterated and their properties (for the provided keys) are removed and then added.
 * Be sure that the key indices have been created prior to calling this method so that they can pick up the property mutations calls.
 * Finally, if the graph is a TransactionalGraph, then a 1000 mutation buffer is used for each commit.
 *
 * @param graph    the graph containing the provided elements
 * @param elements the elements to index into the key indices
 * @param keys     the keys of the key indices
 * @return the number of element properties that were indexed
 */
public static long reIndexElements(final Graph graph, final Iterable<? extends Element> elements, final Set<String> keys) {
    final boolean isTransactional = graph instanceof TransactionalGraph;
    long counter = 0;
    for (final Element element : elements) {
        for (final String key : keys) {
            final Object value = element.removeProperty(key);
            if (null != value) {
                counter++;
                element.setProperty(key, value);


                if (isTransactional && (counter % 1000 == 0)) {
                    ((TransactionalGraph) graph).commit();
                }
            }
        }
    }
    if (isTransactional) {
        ((TransactionalGraph) graph).commit();
    }
    return counter;
}
 

/**
 * Clear all the properties from an iterable of elements.
 *
 * @param elements the elements to remove properties from
 */
public static void removeProperties(final Iterable<Element> elements) {
    for (final Element element : elements) {
        final List<String> keys = new ArrayList<String>();
        keys.addAll(element.getPropertyKeys());
        for (final String key : keys) {
            element.removeProperty(key);
        }
    }
}
 

/**
 * Typecasts a property value. This only works for casting to a class that has a constructor of the for new X(String).
 * If no such constructor exists, a RuntimeException is thrown and the original element property is left unchanged.
 *
 * @param key       the key for the property value to typecast
 * @param classCast the class to typecast to
 * @param elements  the elements to have their property typecasted
 */
public static void typecastProperty(final String key, final Class classCast, final Iterable<Element> elements) {
    for (final Element element : elements) {
        final Object value = element.removeProperty(key);
        if (null != value) {
            try {
                element.setProperty(key, classCast.getConstructor(String.class).newInstance(value.toString()));
            } catch (Exception e) {
                element.setProperty(key, value);
                throw new RuntimeException(e.getMessage(), e);
            }
        }
    }
}
 

/**
 * Renames a property by removing the old key and adding the stored value to the new key.
 * If property does not exist, nothing occurs.
 *
 * @param oldKey   the key to rename
 * @param newKey   the key to rename to
 * @param elements the elements to rename
 */
public static void renameProperty(final String oldKey, final String newKey, final Iterable<Element> elements) {
    for (final Element element : elements) {
        Object value = element.removeProperty(oldKey);
        if (null != value)
            element.setProperty(newKey, value);
    }
}
 

/**
 * Remove a property from all elements in the provided iterable.
 *
 * @param key      the property to remove by key
 * @param elements the elements to remove the property from
 */
public static void removeProperty(final String key, final Iterable<Element> elements) {
    for (final Element element : elements) {
        element.removeProperty(key);
    }
}