| /* |
| * 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.language.grammar; |
| |
| import org.apache.tinkerpop.gremlin.process.traversal.dsl.graph.GraphTraversalSource; |
| |
| /** |
| * Handles transactions via calls to {@code tx()}. |
| */ |
| public class TraversalSourceTxVisitor extends DefaultGremlinBaseVisitor<Void> { |
| private GraphTraversalSource source; |
| private final GremlinAntlrToJava antlr; |
| |
| public TraversalSourceTxVisitor(final GraphTraversalSource source, final GremlinAntlrToJava antlr) { |
| this.source = source; |
| this.antlr = antlr; |
| } |
| |
| @Override |
| public Void visitTransactionPart(final GremlinParser.TransactionPartContext ctx) { |
| // position 4 holds the tx command |
| final String cmd = ctx.getChild(4).getText(); |
| final GraphTraversalSource g = null == source ? antlr.graph.traversal() : source; |
| switch (cmd) { |
| case "begin": |
| // script based transactions are automatic, meaning commit()/rollback() should keep g in a state |
| // where the transaction is opened on the next script execution. begin() is a more necessary syntax in |
| // remote client-side Gremlin where you need to construct a boundary for the session which hosts the |
| // transaction. we support begin() here to at least allow the function to be called without error so |
| // as to hold syntax consistency, but it is effectively a no-op. |
| // g.tx().begin(); |
| break; |
| case "commit": |
| g.tx().commit(); |
| break; |
| case "rollback": |
| g.tx().rollback(); |
| break; |
| default: |
| notImplemented(ctx); |
| break; |
| } |
| |
| return null; |
| } |
| } |