Github user kchilton2 commented on a diff in the pull request:
https://github.com/apache/incubator-rya/pull/291#discussion_r182596490
--- Diff:
common/rya.api/src/main/java/org/apache/rya/api/domain/VarNameUtils.java ---
@@ -0,0 +1,202 @@
+/*
+ * 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.rya.api.domain;
+
+import org.apache.commons.lang.StringUtils;
+import org.eclipse.rdf4j.model.Value;
+import org.eclipse.rdf4j.model.ValueFactory;
+import org.eclipse.rdf4j.model.impl.SimpleValueFactory;
+import org.eclipse.rdf4j.query.algebra.Var;
+import org.eclipse.rdf4j.query.algebra.helpers.TupleExprs;
+
+/**
+ * Utility methods and constants for RDF {@link Var} names.
+ */
+public final class VarNameUtils {
+ private static final ValueFactory VF =
SimpleValueFactory.getInstance();
+
+ /**
+ * Prepended to the start of constant var names.
+ */
+ public static final String CONSTANT_PREFIX = "_const_";
+ private static final String LEGACY_CONSTANT_PREFIX = "-const-";
+
+ /**
+ * Prepended to the start of anonymous var names.
+ */
+ public static final String ANONYMOUS_PREFIX = "_anon_";
+ private static final String LEGACY_ANONYMOUS_PREFIX = "-anon-";
+
+ /**
+ * Private constructor to prevent instantiation.
+ */
+ private VarNameUtils() {
+ }
+
+ /**
+ * Prepends the constant prefix to the specified value.
+ * @param value the value to add the constant prefix to.
+ * @return the value with the constant prefix attached before it.
+ */
+ public static String prependConstant(final String value) {
--- End diff --
Params and return type are @ Nullable
---
