http://git-wip-us.apache.org/repos/asf/geode/blob/be8db8b7/geode-core/src/test/java/org/apache/geode/test/dunit/standalone/VersionManager.java
----------------------------------------------------------------------
diff --git
a/geode-core/src/test/java/org/apache/geode/test/dunit/standalone/VersionManager.java
b/geode-core/src/test/java/org/apache/geode/test/dunit/standalone/VersionManager.java
new file mode 100755
index 0000000..7bda948
--- /dev/null
+++
b/geode-core/src/test/java/org/apache/geode/test/dunit/standalone/VersionManager.java
@@ -0,0 +1,170 @@
+/*
+ * 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.geode.test.dunit.standalone;
+
+import org.apache.geode.test.dunit.Host;
+import org.apache.geode.test.dunit.VM;
+
+import java.io.BufferedReader;
+import java.io.File;
+import java.io.FileReader;
+import java.io.IOException;
+import java.util.ArrayList;
+import java.util.Collections;
+import java.util.HashMap;
+import java.util.List;
+import java.util.Map;
+
+/**
+ * VersionManager loads the class-paths for all of the releases of Geode
configured for
+ * backward-compatibility testing in the geode-core build.gradle file.
+ * <p>
+ * Tests may use these versions in launching VMs to run older clients or
servers.
+ *
+ * @see Host#getVM(String, int)
+ */
+public class VersionManager {
+ public static final String CURRENT_VERSION = "000";
+
+ private static VersionManager instance;
+
+ protected static void init() {
+ instance = new VersionManager();
+ instance.findVersions();
+ }
+
+ public static VersionManager getInstance() {
+ if (instance == null) {
+ init();
+ }
+ return instance;
+ }
+
+ /**
+ * classPaths for old versions loaded from a file generated by Gradle
+ */
+ private Map<String, String> classPaths = new HashMap<>();
+
+ private List<String> testVersions = new ArrayList<String>(10);
+
+ private String oldestVersion;
+
+ /**
+ * Test to see if a version string is known to VersionManager. Versions are
either CURRENT_VERSION
+ * or one of the versions returned by VersionManager#getVersions()
+ */
+ public boolean isValidVersion(String version) {
+ return version.equals(CURRENT_VERSION) || classPaths.containsKey(version);
+ }
+
+ /**
+ * Returns true if the version is equal to the CURRENT_VERSION constant
+ */
+ public static boolean isCurrentVersion(String version) {
+ return version.equals(CURRENT_VERSION);
+ }
+
+ /**
+ * Returns the classPath for the given version, or null if the version is
not valid. Use
+ * CURRENT_VERSION for the version in development.
+ */
+ public String getClasspath(String version) {
+ return classPaths.get(version);
+ }
+
+ /**
+ * Returns a list of older versions available for testing
+ */
+ public List<String> getVersions() {
+ return Collections.unmodifiableList(testVersions);
+ }
+
+ public List<String> getVersionsWithoutCurrent() {
+ List<String> result = new ArrayList<>(testVersions);
+ result.remove(CURRENT_VERSION);
+ return result;
+ }
+
+ /**
+ * returns the oldest version defined in the geodeOldVersionClasspaths.txt
file
+ */
+ public String getOldestVersion() {
+ return oldestVersion;
+ }
+
+ private void findVersions() {
+ // this file is created by the gradle task createClasspathsPropertiesFile
+ File propFile = new
File("../../../geode-old-versions/build/geodeOldVersionClasspaths.txt");
+ if (!propFile.exists()) {
+ // running under an IDE
+ propFile = new
File("../geode-old-versions/build/geodeOldVersionClasspaths.txt");
+ }
+ String oldver = "ZZZ";
+ if (propFile.exists()) {
+ System.out.println("found geodeOldVersionClasspaths.txt - loading
properties");
+ Map<String, String> dunitProperties = loadProperties(propFile);
+ for (Map.Entry<String, String> entry : dunitProperties.entrySet()) {
+ String version = entry.getKey();
+ if (version.startsWith("test") && version.length() >= "test".length())
{
+ if (version.equals("test")) {
+ version = CURRENT_VERSION;
+ } else {
+ version = version.substring("test".length());
+ if (version.compareTo(oldver) < 0) {
+ oldver = version;
+ }
+ }
+ classPaths.put(version, entry.getValue());
+ testVersions.add(version);
+ }
+ }
+ if (oldver.equals("ZZZ")) {
+ oldestVersion = CURRENT_VERSION;
+ } else {
+ oldestVersion = oldver;
+ }
+ } else {
+ System.out.println(
+ "WARNING: could not find geodeTestClasspaths.txt - tests will use
current version");
+ }
+ }
+
+ /**
+ * Loads properties from a file, returning a Map object. Note: this method
cannot use
+ * Properties.load() because that method interprets back-slashes as escape
characters, causing
+ * class-paths on Windows machines to be garbled.
+ */
+ private Map<String, String> loadProperties(File propFile) {
+ Map<String, String> dunitProperties = new HashMap<>();
+ try {
+ String propertyLine;
+ FileReader reader = new FileReader(propFile);
+ BufferedReader breader = new BufferedReader(reader);
+ while ((propertyLine = breader.readLine()) != null) {
+ propertyLine = propertyLine.trim();
+ if (propertyLine.length() != 0 || !propertyLine.startsWith("#")) {
+ String[] split = propertyLine.split("=");
+ dunitProperties.put(split[0], split[1]);
+ }
+ }
+ } catch (IOException e) {
+ e.printStackTrace();
+ }
+ return dunitProperties;
+ }
+
+
+
+}
