1 files changed, 69 insertions, 0 deletions
diff --git a/org.eclipse.jgit.junit/src/org/eclipse/jgit/junit/SeparateClassloaderTestRunner.java b/org.eclipse.jgit.junit/src/org/eclipse/jgit/junit/SeparateClassloaderTestRunner.java
new file mode 100644
index 0000000000..2a482df04a
--- /dev/null
+++ b/org.eclipse.jgit.junit/src/org/eclipse/jgit/junit/SeparateClassloaderTestRunner.java
@@ -0,0 +1,69 @@
+/*
+ * Copyright (C) 2019 Nail Samatov <sanail@yandex.ru> and others
+ *
+ * This program and the accompanying materials are made available under the
+ * terms of the Eclipse Distribution License v. 1.0 which is available at
+ * https://www.eclipse.org/org/documents/edl-v10.php.
+ *
+ * SPDX-License-Identifier: BSD-3-Clause
+ */
+package org.eclipse.jgit.junit;
+
+import java.net.MalformedURLException;
+import java.net.URL;
+import java.net.URLClassLoader;
+import java.nio.file.Paths;
+
+import org.junit.runners.BlockJUnit4ClassRunner;
+import org.junit.runners.model.InitializationError;
+
+/**
+ * This class is used when it's required to load jgit classes in separate
+ * classloader for each test class. It can be needed to isolate static field
+ * initialization between separate tests.
+ *
+ * @since 5.5
+ */
+public class SeparateClassloaderTestRunner extends BlockJUnit4ClassRunner {
+
+	/**
+	 * Creates a SeparateClassloaderTestRunner to run {@code klass}.
+	 *
+	 * @param klass
+	 *            test class to run.
+	 * @throws InitializationError
+	 *             if the test class is malformed or can't be found.
+	 */
+	public SeparateClassloaderTestRunner(Class<?> klass)
+			throws InitializationError {
+		super(loadNewClass(klass));
+	}
+
+	private static Class<?> loadNewClass(Class<?> klass)
+			throws InitializationError {
+		try {
+			String pathSeparator = System.getProperty("path.separator");
+			String[] classPathEntries = System.getProperty("java.class.path")
+					.split(pathSeparator, -1);
+			URL[] urls = new URL[classPathEntries.length];
+			for (int i = 0; i < classPathEntries.length; i++) {
+				urls[i] = Paths.get(classPathEntries[i]).toUri().toURL();
+			}
+			ClassLoader testClassLoader = new URLClassLoader(urls) {
+
+				@Override
+				public Class<?> loadClass(String name)
+						throws ClassNotFoundException {
+					if (name.startsWith("org.eclipse.jgit.")) {
+						return super.findClass(name);
+					}
+
+					return super.loadClass(name);
+				}
+			};
+			return Class.forName(klass.getName(), true, testClassLoader);
+		} catch (ClassNotFoundException | MalformedURLException e) {
+			throw new InitializationError(e);
+		}
+	}
+}