Java tutorial
/* * 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.process.remote; import org.apache.commons.configuration.Configuration; import org.apache.commons.configuration.PropertiesConfiguration; import org.apache.tinkerpop.gremlin.process.computer.GraphComputer; import org.apache.tinkerpop.gremlin.process.remote.traversal.strategy.decoration.RemoteStrategy; import org.apache.tinkerpop.gremlin.process.traversal.TraversalSource; import org.apache.tinkerpop.gremlin.process.traversal.TraversalStrategies; import org.apache.tinkerpop.gremlin.process.traversal.dsl.graph.GraphTraversalSource; import org.apache.tinkerpop.gremlin.structure.Edge; import org.apache.tinkerpop.gremlin.structure.Graph; import org.apache.tinkerpop.gremlin.structure.Transaction; import org.apache.tinkerpop.gremlin.structure.Vertex; import org.apache.tinkerpop.gremlin.structure.util.GraphFactory; import org.apache.tinkerpop.gremlin.structure.util.StringFactory; import org.apache.tinkerpop.gremlin.structure.util.empty.EmptyGraph; import java.lang.reflect.Constructor; import java.util.Collections; import java.util.Iterator; /** * A {@code ServerGraph} represents a proxy by which traversals spawned from this graph are expected over a * {@link RemoteConnection}. This is not a full {@link Graph} implementation in the sense that the most of the methods * will throw an {@link UnsupportedOperationException}. This implementation can only be used for spawning remote * traversal instances. * * @author Stephen Mallette (http://stephen.genoprime.com) * @deprecated As for release 3.2.2, replaced by {@link TraversalSource#withRemote(RemoteConnection)} or its overloads. */ @Graph.OptIn(Graph.OptIn.SUITE_PROCESS_STANDARD) @Graph.OptIn(Graph.OptIn.SUITE_PROCESS_COMPUTER) @Graph.OptOut(test = "org.apache.tinkerpop.gremlin.process.traversal.step.sideEffect.GroupCountTest", method = "g_V_hasXnoX_groupCountXaX_capXaX", reason = "This test asserts an empty side-effect which reflects as a null rather than an \"empty\" and thus doesn't assert") @Graph.OptOut(test = "org.apache.tinkerpop.gremlin.process.traversal.step.map.PeerPressureTest", method = "*", reason = "hmmmm") @Graph.OptOut(test = "org.apache.tinkerpop.gremlin.process.traversal.step.map.PageRankTest", method = "*", reason = "hmmmm") @Graph.OptOut(test = "org.apache.tinkerpop.gremlin.process.traversal.strategy.decoration.TranslationStrategyProcessTest", method = "*", reason = "hmmmm") @Graph.OptOut(test = "org.apache.tinkerpop.gremlin.process.traversal.step.map.ProjectTest", method = "g_V_hasLabelXpersonX_projectXa_bX_byXoutE_countX_byXageX", reason = "Not happy in OLAP.") @Graph.OptOut(test = "org.apache.tinkerpop.gremlin.process.traversal.step.map.ProjectTest", method = "g_V_outXcreatedX_projectXa_bX_byXnameX_byXinXcreatedX_countX_order_byXselectXbX__decrX_selectXaX", reason = "Not happy in OLAP.") @Graph.OptOut(test = "org.apache.tinkerpop.gremlin.process.traversal.CoreTraversalTest", method = "*", reason = "The test suite does not support profiling or lambdas and for groovy tests: 'Could not locate method: GraphTraversalSource.withStrategies([{traversalCategory=interface org.apache.tinkerpop.gremlin.process.traversal.TraversalStrategy$DecorationStrategy}])'") @Graph.OptOut(test = "org.apache.tinkerpop.gremlin.process.traversal.step.map.ProgramTest", method = "*", reason = "RemoteGraph retrieves detached vertices that can't be attached to a remote OLAP graph") @Graph.OptOut(test = "org.apache.tinkerpop.gremlin.process.traversal.strategy.decoration.ElementIdStrategyProcessTest", method = "*", reason = "RemoteGraph does not support ElementIdStrategy at this time - it requires a lambda in construction which is not serializable") @Graph.OptOut(test = "org.apache.tinkerpop.gremlin.process.traversal.strategy.decoration.EventStrategyProcessTest", method = "*", reason = "RemoteGraph does not support EventStrategy at this time - some of its members are not serializable") @Graph.OptOut(test = "org.apache.tinkerpop.gremlin.process.traversal.strategy.decoration.PartitionStrategyProcessTest", method = "*", reason = "RemoteGraph does not support PartitionStrategy at this time") @Graph.OptOut(test = "org.apache.tinkerpop.gremlin.process.traversal.strategy.verification.ReadOnlyStrategyProcessTest", method = "*", reason = "RemoteGraph does not support ReadOnlyStrategy at this time") @Graph.OptOut(test = "org.apache.tinkerpop.gremlin.process.traversal.strategy.decoration.SubgraphStrategyProcessTest", method = "*", reason = "RemoteGraph does not support SubgraphStrategy at this time") @Graph.OptOut(test = "org.apache.tinkerpop.gremlin.process.computer.ranking.pagerank.PageRankVertexProgramTest", method = "*", reason = "RemoteGraph does not support direct Graph.compute() access") @Graph.OptOut(test = "org.apache.tinkerpop.gremlin.process.computer.bulkloading.BulkLoaderVertexProgramTest", method = "*", reason = "RemoteGraph does not support direct Graph.compute() access") @Graph.OptOut(test = "org.apache.tinkerpop.gremlin.process.computer.bulkdumping.BulkDumperVertexProgramTest", method = "*", reason = "RemoteGraph does not support direct Graph.compute() access") @Graph.OptOut(test = "org.apache.tinkerpop.gremlin.process.computer.GraphComputerTest", method = "*", reason = "RemoteGraph does not support direct Graph.compute() access") @Graph.OptOut(test = "org.apache.tinkerpop.gremlin.process.traversal.TraversalInterruptionTest", method = "*", reason = "The interruption model in the test can't guarantee interruption at the right time with RemoteGraph.") @Graph.OptOut(test = "org.apache.tinkerpop.gremlin.process.traversal.TraversalInterruptionComputerTest", method = "*", reason = "The interruption model in the test can't guarantee interruption at the right time with RemoteGraph.") @Deprecated public class RemoteGraph implements Graph { private final RemoteConnection connection; public static final String GREMLIN_REMOTE_GRAPH_REMOTE_CONNECTION_CLASS = "gremlin.remoteGraph.remoteConnectionClass"; static { TraversalStrategies.GlobalCache.registerStrategies(RemoteGraph.class, TraversalStrategies.GlobalCache .getStrategies(EmptyGraph.class).clone().addStrategies(RemoteStrategy.instance())); } private RemoteGraph(final RemoteConnection connection) { this.connection = connection; } /** * Creates a new {@link RemoteGraph} instance using the specified configuration, which allows {@link RemoteGraph} * to be compliant with {@link GraphFactory}. Expects key for {@link #GREMLIN_REMOTE_GRAPH_REMOTE_CONNECTION_CLASS} * as well as any configuration required by the underlying {@link RemoteConnection} which will be instantiated. * Note that the {@code Configuration} object is passed down without change to the creation of the * {@link RemoteConnection} instance. */ public static RemoteGraph open(final Configuration conf) { if (!conf.containsKey(GREMLIN_REMOTE_GRAPH_REMOTE_CONNECTION_CLASS)) throw new IllegalArgumentException( "Configuration must contain the '" + GREMLIN_REMOTE_GRAPH_REMOTE_CONNECTION_CLASS + "' key"); final RemoteConnection remoteConnection; try { final Class<? extends RemoteConnection> clazz = Class .forName(conf.getString(GREMLIN_REMOTE_GRAPH_REMOTE_CONNECTION_CLASS)) .asSubclass(RemoteConnection.class); final Constructor<? extends RemoteConnection> ctor = clazz.getConstructor(Configuration.class); remoteConnection = ctor.newInstance(conf); } catch (Exception ex) { throw new IllegalStateException(ex); } return new RemoteGraph(remoteConnection); } public static RemoteGraph open(final String configFile) throws Exception { return open(new PropertiesConfiguration(configFile)); } /** * Creates a new {@link RemoteGraph} instance. {@link RemoteGraph} will attempt to call the * {@link RemoteConnection#close()} method when the {@link #close()} method is called on this class. * * @param connection the {@link RemoteConnection} instance to use * {@link RemoteConnection} */ public static RemoteGraph open(final RemoteConnection connection) { return new RemoteGraph(connection); } public RemoteConnection getConnection() { return connection; } /** * Closes the underlying {@link RemoteConnection}. */ @Override public void close() throws Exception { connection.close(); } @Override public Vertex addVertex(final Object... keyValues) { throw new UnsupportedOperationException( String.format("RemoteGraph is a proxy to %s - this method is not supported", connection)); } @Override public <C extends GraphComputer> C compute(final Class<C> graphComputerClass) throws IllegalArgumentException { throw new UnsupportedOperationException( String.format("RemoteGraph is a proxy to %s - this method is not supported", connection)); } @Override public GraphComputer compute() throws IllegalArgumentException { throw new UnsupportedOperationException( String.format("RemoteGraph is a proxy to %s - this method is not supported", connection)); } /** * This method returns an empty {@link Iterator} - it is not meant to be called directly. */ @Override public Iterator<Vertex> vertices(final Object... vertexIds) { return Collections.emptyIterator(); } /** * This method returns an empty {@link Iterator} - it is not meant to be called directly. */ @Override public Iterator<Edge> edges(final Object... edgeIds) { return Collections.emptyIterator(); } @Override public Transaction tx() { throw new UnsupportedOperationException( String.format("RemoteGraph is a proxy to %s - this method is not supported", connection)); } @Override public Variables variables() { throw new UnsupportedOperationException( String.format("RemoteGraph is a proxy to %s - this method is not supported", connection)); } @Override public Configuration configuration() { throw new UnsupportedOperationException( String.format("RemoteGraph is a proxy to %s - this method is not supported", connection)); } @Override public Features features() { return RemoteFeatures.INSTANCE; } @Override public String toString() { return StringFactory.graphString(this, connection.toString()); } public static class RemoteFeatures implements Features { static RemoteFeatures INSTANCE = new RemoteFeatures(); private RemoteFeatures() { } @Override public GraphFeatures graph() { return RemoteGraphFeatures.INSTANCE; } } public static class RemoteGraphFeatures implements Features.GraphFeatures { static RemoteGraphFeatures INSTANCE = new RemoteGraphFeatures(); private RemoteGraphFeatures() { } @Override public boolean supportsTransactions() { return false; } @Override public boolean supportsThreadedTransactions() { return false; } } }