Fix global annotations ignored when the class path contains a plus sign

core/src/main/java/org/quickperf/QuickPerfUserConfigClasses.java

@@ -47,7 +47,8 @@ private List<File> findDirectoriesForPackage() throws IOException {
         List<File> dirs = new ArrayList<>();
         while (resources.hasMoreElements()) {
             URL resource = resources.nextElement();
-            String classPath = URLDecoder.decode(resource.getPath(), "UTF-8");
+            // URLDecoder would decode + to a space, but in a URL path + is a plus sign
+            String classPath = URLDecoder.decode(resource.getPath().replace("+", "%2B"), "UTF-8");
             File file = new File(classPath);
             dirs.add(file);
         }

core/src/test/java/org/quickperf/QuickPerfUserConfigClassesTest.java

@@ -0,0 +1,108 @@
+/*
+ * Licensed 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.
+ *
+ * Copyright 2019-2022 the original author or authors.
+ */
+package org.quickperf;
+
+import org.junit.Rule;
+import org.junit.Test;
+import org.junit.rules.TemporaryFolder;
+
+import java.io.File;
+import java.io.IOException;
+import java.io.InputStream;
+import java.net.URL;
+import java.net.URLClassLoader;
+import java.nio.file.Files;
+
+import static org.assertj.core.api.Assertions.assertThat;
+
+public class QuickPerfUserConfigClassesTest {
+
+    @Rule
+    public final TemporaryFolder temporaryFolder = new TemporaryFolder();
+
+    public static class UserConfigClass {}
+
+    @Test public void
+    should_find_a_user_config_class_in_a_directory_whose_path_contains_a_plus_sign() throws Exception {
+
+        // GIVEN
+        File classPathDirectory = createClassPathDirectoryContainingUserConfigClass("my+project");
+        // file:/.../my+project/, as with -cp, Gradle, and the JVM forked by QuickPerf
+        URL classPathUrl = classPathDirectory.toURI().toURL();
+
+        // WHEN
+        Class[] classes = findClassesWithClassPath(classPathUrl);
+
+        // THEN
+        assertThat(classes).containsExactly(UserConfigClass.class);
+
+    }
+
+    @Test public void
+    should_find_a_user_config_class_when_the_plus_sign_of_the_directory_url_is_encoded() throws Exception {
+
+        // GIVEN
+        File classPathDirectory = createClassPathDirectoryContainingUserConfigClass("my+project");
+        // file:/.../my%2Bproject/, as with the manifest-only JAR of Maven Surefire 3 on Windows
+        URL classPathUrl = new URL(classPathDirectory.toURI().toString().replace("+", "%2B"));
+
+        // WHEN
+        Class[] classes = findClassesWithClassPath(classPathUrl);
+
+        // THEN
+        assertThat(classes).containsExactly(UserConfigClass.class);
+
+    }
+
+    @Test public void
+    should_find_a_user_config_class_in_a_directory_whose_path_contains_a_space() throws Exception {
+
+        // GIVEN
+        File classPathDirectory = createClassPathDirectoryContainingUserConfigClass("my project");
+        // file:/.../my%20project/
+        URL classPathUrl = classPathDirectory.toURI().toURL();
+
+        // WHEN
+        Class[] classes = findClassesWithClassPath(classPathUrl);
+
+        // THEN
+        assertThat(classes).containsExactly(UserConfigClass.class);
+
+    }
+
+    private File createClassPathDirectoryContainingUserConfigClass(String directoryName) throws IOException {
+        File classPathDirectory = temporaryFolder.newFolder(directoryName);
+        String classFilePath = UserConfigClass.class.getName().replace('.', '/') + ".class";
+        File classFile = new File(classPathDirectory, classFilePath);
+        classFile.getParentFile().mkdirs();
+        try (InputStream classFileContent = UserConfigClass.class.getClassLoader().getResourceAsStream(classFilePath)) {
+            Files.copy(classFileContent, classFile.toPath());
+        }
+        return classPathDirectory;
+    }
+
+    private Class[] findClassesWithClassPath(URL classPathUrl) throws Exception {
+        Thread currentThread = Thread.currentThread();
+        ClassLoader contextClassLoader = currentThread.getContextClassLoader();
+        // Without a parent, the class loader only finds the org/quickperf directory of classPathUrl
+        URLClassLoader classLoader = new URLClassLoader(new URL[] {classPathUrl}, null);
+        currentThread.setContextClassLoader(classLoader);
+        try {
+            return QuickPerfUserConfigClasses.INSTANCE.findClasses();
+        } finally {
+            currentThread.setContextClassLoader(contextClassLoader);
+            classLoader.close();
+        }
+    }
+
+}