Java VertexProperty.empty方法代码示例

import org.apache.tinkerpop.gremlin.structure.VertexProperty; //导入方法依赖的package包/类
@Override
public <V> VertexProperty<V> getVertexProperty(final Neo4jVertex vertex, final String key) {
    final Neo4jNode node = vertex.getBaseVertex();
    if (node.hasProperty(key)) {
        if (node.getProperty(key).equals(VERTEX_PROPERTY_TOKEN)) {
            if (node.degree(Neo4jDirection.OUTGOING, Graph.Hidden.hide(key)) > 1)
                throw Vertex.Exceptions.multiplePropertiesExistForProvidedKey(key);
            else {
                return (VertexProperty<V>) new Neo4jVertexProperty<>(vertex, node.relationships(Neo4jDirection.OUTGOING, Graph.Hidden.hide(key)).iterator().next().end());
            }
        } else {
            return new Neo4jVertexProperty<>(vertex, key, (V) node.getProperty(key));
        }
    } else
        return VertexProperty.<V>empty();
}
 

import org.apache.tinkerpop.gremlin.structure.VertexProperty; //导入方法依赖的package包/类
/**
 * {@inheritDoc}
 */
@Override
@SuppressWarnings("unchecked")
public <V> VertexProperty<V> property(String key) {
    Objects.requireNonNull(key, "key cannot be null");
    // check we have a property with the given key
    Collection<?> collection = properties.get(key);
    if (collection != null) {
        // check size
        if (collection.size() == 1) {
            // iterator
            Iterator<?> iterator = collection.iterator();
            // advance iterator to first element
            if (iterator.hasNext()) {
                // first element
                return (VertexProperty<V>)iterator.next();
            }
            return VertexProperty.empty();
        }
        // exception
        throw Vertex.Exceptions.multiplePropertiesExistForProvidedKey(key);
    }
    return VertexProperty.empty();
}
 

import org.apache.tinkerpop.gremlin.structure.VertexProperty; //导入方法依赖的package包/类
@Override
protected <V> VertexProperty<V> specificProperty(String key) {
    if (key == NAME && name != null) {
        return new TinkerVertexProperty(this, key, name);
    } else if (key == SONG_TYPE && songType != null) {
        return new TinkerVertexProperty(this, key, songType);
    } else if (key == PERFORMANCES && performances != null) {
        return new TinkerVertexProperty(this, key, performances);
    } else {
        return VertexProperty.empty();
    }
}
 

import org.apache.tinkerpop.gremlin.structure.VertexProperty; //导入方法依赖的package包/类
@Override
protected <V> VertexProperty<V> specificProperty(String key) {
    if (key == NAME && name != null) {
        return new TinkerVertexProperty(this, key, name);
    } else {
        return VertexProperty.empty();
    }
}
 

import org.apache.tinkerpop.gremlin.structure.VertexProperty; //导入方法依赖的package包/类
@Override
public <T> VertexProperty<T> property(String key) {
    T value = value(key);
    if (value == null) {
        return VertexProperty.<T>empty();
    } else {
        return new BitsyVertexProperty<T>(this, key, value);
    }
}
 

import org.apache.tinkerpop.gremlin.structure.VertexProperty; //导入方法依赖的package包/类
@Override
public <V> VertexProperty<V> property(final String key) {
    final VertexProperty<V> vertexProperty = getBaseVertex().<V>property(key);
    return vertexProperty.isPresent() ?
            new HadoopVertexProperty<>((VertexProperty<V>) ((Vertex) this.baseElement).property(key), this) :
            VertexProperty.<V>empty();
}
 

import org.apache.tinkerpop.gremlin.structure.VertexProperty; //导入方法依赖的package包/类
@Override
public <V> VertexProperty<V> property(final String key) {
    if (null != this.properties && this.properties.containsKey(key)) {
        final List<VertexProperty> list = (List) this.properties.get(key);
        if (list.size() > 1)
            throw Vertex.Exceptions.multiplePropertiesExistForProvidedKey(key);
        else
            return list.get(0);
    } else
        return VertexProperty.<V>empty();
}
 

import org.apache.tinkerpop.gremlin.structure.VertexProperty; //导入方法依赖的package包/类
@Override
protected void sideEffect(final Traverser.Admin<S> traverser) {
    final String key = (String) this.parameters.get(traverser, T.key, () -> {
        throw new IllegalStateException("The AddPropertyStep does not have a provided key: " + this);
    }).get(0);
    final Object value = this.parameters.get(traverser, T.value, () -> {
        throw new IllegalStateException("The AddPropertyStep does not have a provided value: " + this);
    }).get(0);
    final Object[] vertexPropertyKeyValues = this.parameters.getKeyValues(traverser, T.key, T.value);

    final Element element = traverser.get();


    if (this.callbackRegistry != null) {
        final Property currentProperty = traverser.get().property(key);
        final boolean newProperty = element instanceof Vertex ? currentProperty == VertexProperty.empty() : currentProperty == Property.empty();
        final Event.ElementPropertyChangedEvent evt;
        if (element instanceof Vertex)
            evt = new Event.VertexPropertyChangedEvent(DetachedFactory.detach((Vertex) element, true), newProperty ? null : DetachedFactory.detach((VertexProperty) currentProperty, true), value, vertexPropertyKeyValues);
        else if (element instanceof Edge)
            evt = new Event.EdgePropertyChangedEvent(DetachedFactory.detach((Edge) element, true), newProperty ? null : DetachedFactory.detach(currentProperty), value);
        else if (element instanceof VertexProperty)
            evt = new Event.VertexPropertyPropertyChangedEvent(DetachedFactory.detach((VertexProperty) element, true), newProperty ? null : DetachedFactory.detach(currentProperty), value);
        else
            throw new IllegalStateException(String.format("The incoming object cannot be processed by change eventing in %s:  %s", AddPropertyStep.class.getName(), element));

        this.callbackRegistry.getCallbacks().forEach(c -> c.accept(evt));
    }

    if (null != this.cardinality)
        ((Vertex) element).property(this.cardinality, key, value, vertexPropertyKeyValues);
    else if (vertexPropertyKeyValues.length > 0)
        ((Vertex) element).property(key, value, vertexPropertyKeyValues);
    else
        element.property(key, value);
}
 

import org.apache.tinkerpop.gremlin.structure.VertexProperty; //导入方法依赖的package包/类
@Override
public <V> VertexProperty<V> property(final String key) {
    V value = getProperty(key);
    return value != null ? new HBaseVertexProperty<>(graph, this, key, value) : VertexProperty.empty();
}
 

import org.apache.tinkerpop.gremlin.structure.VertexProperty; //导入方法依赖的package包/类
@Override
public <V> VertexProperty<V> getVertexProperty(final Neo4jVertex vertex, final String key) {
    return vertex.getBaseVertex().hasProperty(key) ? new Neo4jVertexProperty<>(vertex, key, (V) vertex.getBaseVertex().getProperty(key)) : VertexProperty.<V>empty();
}