| /* |
| * Licensed to the Apache Software Foundation (ASF) under one |
| * or more contributor license agreements. See the NOTICE file |
| * distributed with this work for additional information |
| * regarding copyright ownership. The ASF licenses this file |
| * to you under the Apache License, Version 2.0 (the |
| * "License"); you may not use this file except in compliance |
| * with the License. You may obtain a copy of the License at |
| * |
| * http://www.apache.org/licenses/LICENSE-2.0 |
| * |
| * Unless required by applicable law or agreed to in writing, |
| * software distributed under the License is distributed on an |
| * "AS IS" BASIS, WITHOUT WARRANTIES OR CONDITIONS OF ANY |
| * KIND, either express or implied. See the License for the |
| * specific language governing permissions and limitations |
| * under the License. |
| */ |
| package org.apache.tinkerpop.gremlin.structure.util; |
| |
| import org.apache.tinkerpop.gremlin.structure.Edge; |
| import org.apache.tinkerpop.gremlin.structure.Element; |
| import org.apache.tinkerpop.gremlin.structure.Graph; |
| import org.apache.tinkerpop.gremlin.structure.Property; |
| import org.apache.tinkerpop.gremlin.structure.T; |
| import org.apache.tinkerpop.gremlin.structure.Vertex; |
| import org.apache.tinkerpop.gremlin.structure.VertexProperty; |
| import org.javatuples.Pair; |
| |
| import java.util.ArrayList; |
| import java.util.Arrays; |
| import java.util.HashMap; |
| import java.util.HashSet; |
| import java.util.Iterator; |
| import java.util.List; |
| import java.util.Map; |
| import java.util.Objects; |
| import java.util.Optional; |
| import java.util.Set; |
| import java.util.stream.Collectors; |
| import java.util.stream.IntStream; |
| import java.util.stream.Stream; |
| |
| /** |
| * Utility class supporting common functions for {@link Element}. |
| * |
| * @author Marko A. Rodriguez (http://markorodriguez.com) |
| * @author Stephen Mallette (http://stephen.genoprime.com) |
| */ |
| public final class ElementHelper { |
| |
| private ElementHelper() { |
| } |
| |
| /** |
| * Determine whether the {@link Element} label can be legally set. This is typically used as a pre-condition check. |
| * |
| * @param label the element label |
| * @throws IllegalArgumentException whether the label is legal and if not, a clear reason exception is provided |
| */ |
| public static void validateLabel(final String label) throws IllegalArgumentException { |
| if (null == label) |
| throw Element.Exceptions.labelCanNotBeNull(); |
| if (label.isEmpty()) |
| throw Element.Exceptions.labelCanNotBeEmpty(); |
| if (Graph.Hidden.isHidden(label)) |
| throw Element.Exceptions.labelCanNotBeAHiddenKey(label); |
| } |
| |
| /** |
| * Determines whether the property key/value for the specified thing can be legally set. This is typically used as |
| * a pre-condition check prior to setting a property. |
| * |
| * @param key the key of the property |
| * @param value the value of the property\ |
| * @throws IllegalArgumentException whether the key/value pair is legal and if not, a clear reason exception |
| * message is provided |
| */ |
| public static void validateProperty(final String key, final Object value) throws IllegalArgumentException { |
| if (null == key) |
| throw Property.Exceptions.propertyKeyCanNotBeNull(); |
| if (key.isEmpty()) |
| throw Property.Exceptions.propertyKeyCanNotBeEmpty(); |
| if (Graph.Hidden.isHidden(key)) |
| throw Property.Exceptions.propertyKeyCanNotBeAHiddenKey(key); |
| } |
| |
| /** |
| * Determines whether a list of key/values are legal, ensuring that there are an even number of values submitted |
| * and that the keys in the list of arguments are {@link String} or {@link T} objects. |
| * |
| * @param propertyKeyValues a list of key/value pairs |
| * @throws IllegalArgumentException if something in the pairs is illegal |
| */ |
| public static void legalPropertyKeyValueArray(final Object... propertyKeyValues) throws IllegalArgumentException { |
| if (propertyKeyValues.length % 2 != 0) |
| throw Element.Exceptions.providedKeyValuesMustBeAMultipleOfTwo(); |
| for (int i = 0; i < propertyKeyValues.length; i = i + 2) { |
| if (!(propertyKeyValues[i] instanceof String) && !(propertyKeyValues[i] instanceof T)) |
| throw Element.Exceptions.providedKeyValuesMustHaveALegalKeyOnEvenIndices(); |
| } |
| } |
| |
| /** |
| * Extracts the value of the {@link T#id} key from the list of arguments. |
| * |
| * @param keyValues a list of key/value pairs |
| * @return the value associated with {@link T#id} |
| */ |
| public static Optional<Object> getIdValue(final Object... keyValues) { |
| for (int i = 0; i < keyValues.length; i = i + 2) { |
| if (keyValues[i].equals(T.id)) |
| return Optional.ofNullable(keyValues[i + 1]); |
| } |
| return Optional.empty(); |
| } |
| |
| /** |
| * Remove a key from the set of key/value pairs. Assumes that validations have already taken place to |
| * assure that key positions contain strings and that there are an even number of elements. If after removal |
| * there are no values left, the key value list is returned as empty. |
| * |
| * @param keyToRemove the key to remove |
| * @param keyValues the list to remove the accessor from |
| * @return the key/values without the specified accessor or an empty array if no values remain after removal |
| */ |
| public static Optional<Object[]> remove(final String keyToRemove, final Object... keyValues) { |
| return ElementHelper.remove((Object) keyToRemove, keyValues); |
| } |
| |
| /** |
| * Removes an accessor from the set of key/value pairs. Assumes that validations have already taken place to |
| * assure that key positions contain strings and that there are an even number of elements. If after removal |
| * there are no values left, the key value list is returned as empty. |
| * |
| * @param accessor to remove |
| * @param keyValues the list to remove the accessor from |
| * @return the key/values without the specified accessor or an empty array if no values remain after removal |
| */ |
| public static Optional<Object[]> remove(final T accessor, final Object... keyValues) { |
| return ElementHelper.remove((Object) accessor, keyValues); |
| } |
| |
| private static Optional<Object[]> remove(final Object keyToRemove, final Object... keyValues) { |
| final List list = Arrays.asList(keyValues); |
| final List revised = IntStream.range(0, list.size()) |
| .filter(i -> i % 2 == 0) |
| .filter(i -> !keyToRemove.equals(list.get(i))) |
| .flatMap(i -> IntStream.of(i, i + 1)) |
| .mapToObj(i -> list.get(i)) |
| .collect(Collectors.toList()); |
| return revised.size() > 0 ? Optional.of(revised.toArray()) : Optional.empty(); |
| } |
| |
| /** |
| * Append a key/value pair to a list of existing key/values. If the key already exists in the keyValues then |
| * that value is overwritten with the provided value. |
| */ |
| public static Object[] upsert(final Object[] keyValues, final Object key, final Object val) { |
| if (!getKeys(keyValues).contains(key)) |
| return Stream.concat(Stream.of(keyValues), Stream.of(key, val)).toArray(); |
| else { |
| final Object[] kvs = new Object[keyValues.length]; |
| for (int i = 0; i < keyValues.length; i = i + 2) { |
| kvs[i] = keyValues[i]; |
| if (keyValues[i].equals(key)) |
| kvs[i + 1] = val; |
| else |
| kvs[i + 1] = keyValues[i + 1]; |
| } |
| |
| return kvs; |
| } |
| } |
| |
| /** |
| * Replaces one key with a different key. |
| * |
| * @param keyValues the list of key/values to alter |
| * @param oldKey the key to replace |
| * @param newKey the new key |
| */ |
| public static Object[] replaceKey(final Object[] keyValues, final Object oldKey, final Object newKey) { |
| final Object[] kvs = new Object[keyValues.length]; |
| for (int i = 0; i < keyValues.length; i = i + 2) { |
| if (keyValues[i].equals(oldKey)) |
| kvs[i] = newKey; |
| else |
| kvs[i] = keyValues[i]; |
| kvs[i + 1] = keyValues[i + 1]; |
| } |
| |
| return kvs; |
| } |
| |
| /** |
| * Converts a set of key values to a Map. Assumes that validations have already taken place to |
| * assure that key positions contain strings and that there are an even number of elements. |
| */ |
| public static Map<String, Object> asMap(final Object... keyValues) { |
| return asPairs(keyValues).stream().collect(Collectors.toMap(Pair::getValue0, Pair::getValue1)); |
| } |
| |
| /** |
| * Convert a set of key values to a list of Pair objects. Assumes that validations have already taken place to |
| * assure that key positions contain strings and that there are an even number of elements. |
| */ |
| public static List<Pair<String, Object>> asPairs(final Object... keyValues) { |
| final List<Object> list = Arrays.asList(keyValues); |
| return IntStream.range(1, list.size()) |
| .filter(i -> i % 2 != 0) |
| .mapToObj(i -> Pair.with(list.get(i - 1).toString(), list.get(i))) |
| .collect(Collectors.toList()); |
| } |
| |
| /** |
| * Gets the list of keys from the key values. |
| * |
| * @param keyValues a list of key/values pairs |
| */ |
| public static Set<String> getKeys(final Object... keyValues) { |
| final Set<String> keys = new HashSet<>(); |
| for (int i = 0; i < keyValues.length; i = i + 2) { |
| keys.add(keyValues[i].toString()); |
| } |
| return keys; |
| } |
| |
| /** |
| * Extracts the value of the {@link T#label} key from the list of arguments. |
| * |
| * @param keyValues a list of key/value pairs |
| * @return the value associated with {@link T#label} |
| * @throws ClassCastException if the value of the label is not a {@link String} |
| * @throws NullPointerException if the value for the {@link T#label} key is {@code null} |
| */ |
| public static Optional<String> getLabelValue(final Object... keyValues) { |
| for (int i = 0; i < keyValues.length; i = i + 2) { |
| if (keyValues[i].equals(T.label)) { |
| ElementHelper.validateLabel((String) keyValues[i + 1]); |
| return Optional.of((String) keyValues[i + 1]); |
| } |
| } |
| return Optional.empty(); |
| } |
| |
| /** |
| * Assign key/value pairs as properties to an {@link Element}. If the value of {@link T#id} or |
| * {@link T#label} is in the set of pairs, then they are ignored. |
| * |
| * @param element the graph element to assign the {@code propertyKeyValues} |
| * @param propertyKeyValues the key/value pairs to assign to the {@code element} |
| * @throws ClassCastException if the value of the key is not a {@link String} |
| * @throws IllegalArgumentException if the value of {@code element} is null |
| */ |
| public static void attachProperties(final Element element, final Object... propertyKeyValues) { |
| if (null == element) |
| throw Graph.Exceptions.argumentCanNotBeNull("element"); |
| |
| final boolean allowNullPropertyValues = element instanceof Vertex ? |
| element.graph().features().vertex().supportsNullPropertyValues() : element instanceof Edge ? |
| element.graph().features().edge().supportsNullPropertyValues() : |
| element.graph().features().vertex().properties().supportsNullPropertyValues(); |
| |
| for (int i = 0; i < propertyKeyValues.length; i = i + 2) { |
| if (!propertyKeyValues[i].equals(T.id) && !propertyKeyValues[i].equals(T.label)) |
| if (!allowNullPropertyValues && null == propertyKeyValues[i + 1]) |
| element.properties(((String) propertyKeyValues[i])).forEachRemaining(Property::remove); |
| else |
| element.property((String) propertyKeyValues[i], propertyKeyValues[i + 1]); |
| } |
| } |
| |
| /** |
| * Assign key/value pairs as properties to an {@link Vertex}. If the value of {@link T#id} or {@link T#label} is |
| * in the set of pairs, then they are ignored. The {@link VertexProperty.Cardinality} of the key is determined from |
| * the {@link Graph.Features.VertexFeatures}. |
| * |
| * @param vertex the graph vertex to assign the {@code propertyKeyValues} |
| * @param propertyKeyValues the key/value pairs to assign to the {@code element} |
| * @throws ClassCastException if the value of the key is not a {@link String} |
| * @throws IllegalArgumentException if the value of {@code element} is null |
| */ |
| public static void attachProperties(final Vertex vertex, final Object... propertyKeyValues) { |
| if (null == vertex) |
| throw Graph.Exceptions.argumentCanNotBeNull("vertex"); |
| |
| final boolean allowNullPropertyValues = vertex.graph().features().vertex().supportsNullPropertyValues(); |
| |
| for (int i = 0; i < propertyKeyValues.length; i = i + 2) { |
| if (!propertyKeyValues[i].equals(T.id) && !propertyKeyValues[i].equals(T.label)) |
| if (!allowNullPropertyValues && null == propertyKeyValues[i + 1]) |
| vertex.properties(((String) propertyKeyValues[i])).forEachRemaining(VertexProperty::remove); |
| else |
| vertex.property(vertex.graph().features().vertex().getCardinality((String) propertyKeyValues[i]), (String) propertyKeyValues[i], propertyKeyValues[i + 1]); |
| } |
| } |
| |
| /** |
| * Assign key/value pairs as properties to a {@link Vertex}. If the value of {@link T#id} or {@link T#label} is |
| * in the set of pairs, then they are ignored. |
| * |
| * @param vertex the vertex to attach the properties to |
| * @param cardinality the cardinality of the key value pair settings |
| * @param propertyKeyValues the key/value pairs to assign to the {@code element} |
| * @throws ClassCastException if the value of the key is not a {@link String} |
| * @throws IllegalArgumentException if the value of {@code element} is null |
| */ |
| public static void attachProperties(final Vertex vertex, final VertexProperty.Cardinality cardinality, |
| final Object... propertyKeyValues) { |
| if (null == vertex) |
| throw Graph.Exceptions.argumentCanNotBeNull("vertex"); |
| |
| final boolean allowNullPropertyValues = vertex.graph().features().vertex().supportsNullPropertyValues(); |
| |
| for (int i = 0; i < propertyKeyValues.length; i = i + 2) { |
| if (!propertyKeyValues[i].equals(T.id) && !propertyKeyValues[i].equals(T.label)) |
| if (!allowNullPropertyValues && null == propertyKeyValues[i + 1]) |
| vertex.properties(((String) propertyKeyValues[i])).forEachRemaining(VertexProperty::remove); |
| else |
| vertex.property(cardinality, (String) propertyKeyValues[i], propertyKeyValues[i + 1]); |
| } |
| } |
| |
| /** |
| * This is a helper method for dealing with vertex property cardinality and typically used in {@link Vertex#property(VertexProperty.Cardinality, String, Object, Object...)}. |
| * If the cardinality is list, simply return {@link Optional#empty}. |
| * If the cardinality is single, delete all existing properties of the provided key and return {@link Optional#empty}. |
| * If the cardinality is set, find one that has the same key/value and attached the properties to it and return it. Else, if no equal value is found, return {@link Optional#empty}. |
| * |
| * @param vertex the vertex to stage a vertex property for |
| * @param cardinality the cardinality of the vertex property |
| * @param key the key of the vertex property |
| * @param value the value of the vertex property |
| * @param keyValues the properties of vertex property |
| * @param <V> the type of the vertex property value |
| * @return a vertex property if it has been found in set with equal value |
| */ |
| public static <V> Optional<VertexProperty<V>> stageVertexProperty(final Vertex vertex, |
| final VertexProperty.Cardinality cardinality, |
| final String key, final V value, final Object... keyValues) { |
| if (cardinality.equals(VertexProperty.Cardinality.single)) |
| vertex.properties(key).forEachRemaining(VertexProperty::remove); |
| else if (cardinality.equals(VertexProperty.Cardinality.set)) { |
| final Iterator<VertexProperty<V>> itty = vertex.properties(key); |
| while (itty.hasNext()) { |
| final VertexProperty<V> property = itty.next(); |
| if (property.value().equals(value)) { |
| ElementHelper.attachProperties(property, keyValues); |
| return Optional.of(property); |
| } |
| } |
| } // do nothing on Cardinality.list |
| return Optional.empty(); |
| } |
| |
| /** |
| * Retrieve the properties associated with a particular element. |
| * The result is a Object[] where odd indices are String keys and even indices are the values. |
| * |
| * @param element the element to retrieve properties from |
| * @param includeId include Element.ID in the key/value list |
| * @param includeLabel include Element.LABEL in the key/value list |
| * @param propertiesToCopy the properties to include with an empty list meaning copy all properties |
| * @return a key/value array of properties where odd indices are String keys and even indices are the values. |
| */ |
| public static Object[] getProperties(final Element element, final boolean includeId, final boolean includeLabel, final Set<String> propertiesToCopy) { |
| final List<Object> keyValues = new ArrayList<>(); |
| if (includeId) { |
| keyValues.add(T.id); |
| keyValues.add(element.id()); |
| } |
| if (includeLabel) { |
| keyValues.add(T.label); |
| keyValues.add(element.label()); |
| } |
| element.keys().forEach(key -> { |
| if (propertiesToCopy.isEmpty() || propertiesToCopy.contains(key)) { |
| keyValues.add(key); |
| keyValues.add(element.value(key)); |
| } |
| }); |
| return keyValues.toArray(new Object[keyValues.size()]); |
| } |
| |
| /** |
| * A standard method for determining if two {@link Element} objects are equal. This method should be used by any |
| * {@link Object#equals(Object)} implementation to ensure consistent behavior. This method is used for Vertex, |
| * Edge, and VertexProperty. |
| * |
| * @param a The first {@link Element} |
| * @param b The second {@link Element} (as an {@link Object}) |
| * @return true if elements and equal and false otherwise |
| */ |
| public static boolean areEqual(final Element a, final Object b) { |
| if (a == b) |
| return true; |
| if (null == b || null == a) |
| return false; |
| if (!((a instanceof Vertex && b instanceof Vertex) || |
| (a instanceof Edge && b instanceof Edge) || |
| (a instanceof VertexProperty && b instanceof VertexProperty))) |
| return false; |
| return haveEqualIds(a, (Element) b); |
| } |
| |
| public static boolean areEqual(final Vertex a, final Vertex b) { |
| return null != b && null != a && (a == b || haveEqualIds(a, b)); |
| } |
| |
| public static boolean areEqual(final Edge a, final Edge b) { |
| return null != b && null != a && (a == b || haveEqualIds(a, b)); |
| } |
| |
| public static boolean areEqual(final VertexProperty a, final VertexProperty b) { |
| return null != b && null != a && (a == b || haveEqualIds(a, b)); |
| } |
| |
| /** |
| * A standard method for determining if two {@link VertexProperty} objects are equal. This method should be used by any |
| * {@link Object#equals(Object)} implementation to ensure consistent behavior. |
| * |
| * @param a the first {@link VertexProperty} |
| * @param b the second {@link VertexProperty} |
| * @return true if equal and false otherwise |
| */ |
| public static boolean areEqual(final VertexProperty a, final Object b) { |
| return ElementHelper.areEqual((Element) a, b); |
| } |
| |
| /** |
| * Simply tests if the value returned from {@link Element#id()} are {@code equal()}. |
| * |
| * @param a the first {@link Element} |
| * @param b the second {@link Element} |
| * @return true if ids are equal and false otherwise |
| */ |
| public static boolean haveEqualIds(final Element a, final Element b) { |
| return a.id().equals(b.id()); |
| } |
| |
| /** |
| * If two {@link Element} instances are equal, then they must have the same hash codes. This methods ensures consistent hashCode values. |
| * |
| * @param element the element to get the hashCode for |
| * @return the hash code of the element |
| */ |
| public static int hashCode(final Element element) { |
| return element.id().hashCode(); |
| } |
| |
| /** |
| * If two {@link Property} instances are equal, then they must have the same hash codes. This methods ensures consistent hashCode values. |
| * For {@link VertexProperty} use {@link ElementHelper#hashCode(Element)}. |
| * |
| * @param property the property to get the hashCode for |
| * @return the hash code of the property |
| */ |
| public static int hashCode(final Property property) { |
| return property.key().hashCode() + Objects.hashCode(property.value()); |
| } |
| |
| /** |
| * A standard method for determining if two {@link Property} objects are equal. This method should be used by any |
| * {@link Object#equals(Object)} implementation to ensure consistent behavior. |
| * |
| * @param a the first {@link Property} |
| * @param b the second {@link Property} |
| * @return true if equal and false otherwise |
| */ |
| public static boolean areEqual(final Property a, final Object b) { |
| if (a == b) |
| return true; |
| if (null == b || null == a) |
| return false; |
| if (!(b instanceof Property)) |
| return false; |
| if (!a.isPresent() && !((Property) b).isPresent()) |
| return true; |
| if (!a.isPresent() && ((Property) b).isPresent() || a.isPresent() && !((Property) b).isPresent()) |
| return false; |
| return a.key().equals(((Property) b).key()) && a.value().equals(((Property) b).value()); |
| |
| } |
| |
| public static Map<String, Object> propertyValueMap(final Element element, final String... propertyKeys) { |
| final Map<String, Object> values = new HashMap<>(); |
| element.properties(propertyKeys).forEachRemaining(property -> values.put(property.key(), property.value())); |
| return values; |
| } |
| |
| public static Map<String, Property> propertyMap(final Element element, final String... propertyKeys) { |
| final Map<String, Property> propertyMap = new HashMap<>(); |
| element.properties(propertyKeys).forEachRemaining(property -> propertyMap.put(property.key(), property)); |
| return propertyMap; |
| } |
| |
| public static Map<String, List> vertexPropertyValueMap(final Vertex vertex, final String... propertyKeys) { |
| final Map<String, List> valueMap = new HashMap<>(); |
| vertex.properties(propertyKeys).forEachRemaining(property -> { |
| if (valueMap.containsKey(property.key())) |
| valueMap.get(property.key()).add(property.value()); |
| else { |
| final List list = new ArrayList(); |
| list.add(property.value()); |
| valueMap.put(property.key(), list); |
| } |
| }); |
| return valueMap; |
| } |
| |
| public static Map<String, List<VertexProperty>> vertexPropertyMap(final Vertex vertex, final String... propertyKeys) { |
| final Map<String, List<VertexProperty>> propertyMap = new HashMap<>(); |
| vertex.properties(propertyKeys).forEachRemaining(property -> { |
| if (propertyMap.containsKey(property.key())) |
| propertyMap.get(property.key()).add(property); |
| else { |
| final List<VertexProperty> list = new ArrayList<>(); |
| list.add(property); |
| propertyMap.put(property.key(), list); |
| } |
| }); |
| return propertyMap; |
| } |
| |
| /** |
| * Checks if a key exists within a list of provided keys. Returns {@code false} if the key is {@code null} or if |
| * the {@link Graph.Hidden}. Returns {@code true} if no {@code providedKeys} are supplied. |
| * |
| * @param key must not be {@code null} |
| */ |
| public static boolean keyExists(final String key, final String... providedKeys) { |
| Objects.requireNonNull(key); |
| if (Graph.Hidden.isHidden(key)) return false; |
| if (null == providedKeys || 0 == providedKeys.length) return true; |
| if (1 == providedKeys.length) return key.equals(providedKeys[0]); |
| else { |
| for (final String temp : providedKeys) { |
| if (key.equals(temp)) |
| return true; |
| } |
| return false; |
| } |
| } |
| |
| public static boolean idExists(final Object id, final Object... providedIds) { |
| if (0 == providedIds.length) return true; |
| |
| // it is OK to evaluate equality of ids via toString() now given that the toString() the test suite |
| // enforces the value of id.()toString() to be a first class representation of the identifier |
| if (1 == providedIds.length) { |
| return id != null && providedIds[0] != null && id.toString().equals(providedIds[0].toString()); |
| } else { |
| for (final Object temp : providedIds) { |
| if (id != null && temp != null && temp.toString().equals(id.toString())) |
| return true; |
| } |
| return false; |
| } |
| } |
| } |