Allow usage of Java Single File Launcher in non-Java projects

java/java.file.launcher/nbproject/project.xml

@@ -299,6 +299,10 @@
                         <code-name-base>org.netbeans.modules.projectapi.nb</code-name-base>
                         <compile-dependency/>
                     </test-dependency>
+                    <test-dependency>
+                        <code-name-base>org.netbeans.modules.maven</code-name-base>
+                        <recursive/>
+                    </test-dependency>
                 </test-type>
             </test-dependencies>
             <friend-packages>

java/java.file.launcher/src/org/netbeans/modules/java/file/launcher/SingleSourceFileUtil.java

@@ -33,6 +33,9 @@
 import org.netbeans.api.java.platform.JavaPlatform;
 import org.netbeans.api.java.platform.JavaPlatformManager;
 import org.netbeans.api.project.FileOwnerQuery;
+import org.netbeans.api.project.Project;
+import org.netbeans.api.project.ProjectUtils;
+import org.netbeans.api.project.SourceGroup;
 import org.netbeans.modules.java.file.launcher.queries.MultiSourceRootProvider;
 import org.netbeans.modules.java.file.launcher.spi.SingleFileOptionsQueryImplementation;
 import org.netbeans.spi.java.queries.CompilerOptionsQueryImplementation;
@@ -88,16 +91,39 @@ public static boolean isSingleSourceFile(FileObject fObj) {
         return true;
     }
 
+    /**
+     * Find a Java-like project that owns the file.
+     *
+     * @param file the file to find project for
+     * @return the project (if it has some Java sources) or {@code null} otherwise
+     */
+    public static Project findJavaOwner(FileObject file) {
+        Project owner = FileOwnerQuery.getOwner(file);
+        if (owner != null) {
+            SourceGroup[] javaSources = ProjectUtils.getSources(owner).getSourceGroups("java"); // NOI18N
+            if (javaSources.length > 0) {
+                return owner;
+            }
+        }
+        return null;
+    }
+
     public static boolean isSupportedFile(FileObject file) {
         if (file == null) {
             return false;
         }
         try {
             FileObject dir = file.getParent();
             File dirFile = dir != null ? FileUtil.toFile(dir) : null;
-            return !MultiSourceRootProvider.DISABLE_MULTI_SOURCE_ROOT
-                    && FileOwnerQuery.getOwner(file) == null
-                    && !file.getFileSystem().isReadOnly()
+            if (MultiSourceRootProvider.DISABLE_MULTI_SOURCE_ROOT) {
+                return false;
+            }
+            Project owner = findJavaOwner(file);
+            if (owner != null) {
+                // no Single Java file support in Java projects
+                return false;
+            }
+            return !file.getFileSystem().isReadOnly()
                     && !(dirFile != null
                     && dirFile.getName().startsWith("vcs-")
                     && dirFile.getAbsolutePath().startsWith(System.getProperty("java.io.tmpdir")));

java/java.file.launcher/src/org/netbeans/modules/java/file/launcher/queries/MultiSourceRootProvider.java

@@ -489,7 +489,7 @@ private static final class RootPathResourceImplementation implements FilteringPa
         private final URL[] roots;
         private final AtomicReference<String> lastCheckedAsIncluded = new AtomicReference<>();
 
-        public RootPathResourceImplementation(FileObject root) {
+        RootPathResourceImplementation(FileObject root) {
             this.root = root.toURL();
             this.roots = new URL[] {this.root};
         }
@@ -507,7 +507,7 @@ public boolean includes(URL root, String resource) {
             }
             FileObject fo = URLMapper.findFileObject(root);
             fo = fo != null ? fo.getFileObject(resource) : null;
-            boolean included = fo == null || FileOwnerQuery.getOwner(fo) == null;
+            boolean included = fo == null || SingleSourceFileUtil.findJavaOwner(fo) == null;
             if (included) {
                 lastCheckedAsIncluded.set(resource);
             }

java/java.file.launcher/test/unit/src/org/netbeans/modules/java/file/launcher/actions/JavaFileTest.java

@@ -19,32 +19,43 @@
 package org.netbeans.modules.java.file.launcher.actions;
 
 import java.io.BufferedReader;
-import java.io.File;
-import java.io.FileWriter;
 import java.io.InputStreamReader;
+import java.io.OutputStreamWriter;
 import static junit.framework.TestCase.assertEquals;
 import org.netbeans.api.extexecution.base.ExplicitProcessParameters;
+import org.netbeans.api.project.Project;
+import org.netbeans.api.project.ProjectManager;
+import org.netbeans.api.project.ProjectUtils;
+import org.netbeans.api.project.SourceGroup;
 import org.netbeans.junit.NbTestCase;
 import org.netbeans.modules.java.file.launcher.SingleSourceFileUtil;
+import org.netbeans.spi.project.ActionProvider;
 import org.openide.filesystems.FileObject;
 import org.openide.filesystems.FileUtil;
+import org.openide.util.Lookup;
+import org.openide.util.lookup.Lookups;
 
 /**
  *
  * @author Sarvesh Kesharwani
  */
 public class JavaFileTest extends NbTestCase {
-
+
+    private FileObject javaFO;
+
     public JavaFileTest(String name) {
         super(name);
     }
-
-    public void testSingleJavaSourceRun() throws Exception {
+
+    @Override
+    protected void setUp() throws Exception {
         clearWorkDir();
-        File f1 = new File(getWorkDir(), "TestSingleJavaFile.java");
-        try (FileWriter w = new FileWriter(f1)) {
+        FileObject root = FileUtil.toFileObject(getWorkDir());
+        root.setAttribute("fallback", true);
+        javaFO = root.createData("TestSingleJavaFile.java");
+        try (var w = new OutputStreamWriter(javaFO.getOutputStream())) {
             w.write(
-                """
+                    """
                 public class TestSingleJavaFile {
                     public static void main (String args[]) {
                         System.out.print("hello world");
@@ -53,8 +64,11 @@ public static void main (String args[]) {
                 """
             );
         }
-        FileObject javaFO = FileUtil.toFileObject(f1);
-        assertNotNull("FileObject found: " + f1, javaFO);
+    }
+
+
+
+    public void testSingleJavaSourceRun() throws Exception {
         SingleJavaSourceRunActionProvider runActionProvider = new SingleJavaSourceRunActionProvider();
         LaunchProcess process = runActionProvider.invokeActionHelper("run.single", javaFO, ExplicitProcessParameters.empty());
         BufferedReader reader
@@ -79,9 +93,64 @@ public static void main (String args[]) {
             }
         }
     }
-
+    public void testSingleFileRunAvailableInNoProject() throws Exception {
+        FileObject fallbackDir = FileUtil.toFileObject(getWorkDir());
+
+        Lookup lkp = Lookups.fixed(javaFO);
+
+        SingleJavaSourceRunActionProvider ap = new SingleJavaSourceRunActionProvider();
+        boolean runEnabled = ap.isActionEnabled(ActionProvider.COMMAND_RUN_SINGLE, lkp);
+        assertTrue("Run is enabled in Java-less project", runEnabled);
+        boolean debugEnabled = ap.isActionEnabled(ActionProvider.COMMAND_DEBUG_SINGLE, lkp);
+        assertTrue("Run is enabled in Java-less project", debugEnabled);
+    }
+
+    public void testSingleFileRunAvailableInFallbackProject() throws Exception {
+        FileObject fallbackDir = FileUtil.toFileObject(getWorkDir());
+        Project fallback = ProjectManager.getDefault().findProject(fallbackDir);
+        assertNotNull("Fallback project found", fallback);
+        final SourceGroup[] srcGroups = ProjectUtils.getSources(fallback).getSourceGroups("java");
+        assertEquals("No Java sources in there", 0, srcGroups.length);
+
+        Lookup lkp = Lookups.fixed(javaFO);
+
+        SingleJavaSourceRunActionProvider ap = new SingleJavaSourceRunActionProvider();
+        boolean runEnabled = ap.isActionEnabled(ActionProvider.COMMAND_RUN_SINGLE, lkp);
+        assertTrue("Run is enabled in Java-less project", runEnabled);
+        boolean debugEnabled = ap.isActionEnabled(ActionProvider.COMMAND_DEBUG_SINGLE, lkp);
+        assertTrue("Run is enabled in Java-less project", debugEnabled);
+    }
+
+    public void testSingleFileRunDisableInAMavenProject() throws Exception {
+        FileObject mavenDir = FileUtil.toFileObject(getWorkDir());
+        FileObject pom = mavenDir.createData("pom.xml");
+        try (var os = pom.getOutputStream()) {
+            os.write("""
+            <project>
+              <modelVersion>4.0.0</modelVersion>
+              <groupId>com.example</groupId>
+              <artifactId>my-app</artifactId>
+              <version>1.0.0</version>
+            </project>
+            """.getBytes());
+        }
+        FileObject emptyJava = FileUtil.createData(mavenDir, "src/main/java/org/Empty.java");
+        Project mavenPrj = ProjectManager.getDefault().findProject(mavenDir);
+        assertNotNull("Found Maven project", mavenPrj);
+        final SourceGroup[] srcGroups = ProjectUtils.getSources(mavenPrj).getSourceGroups("java");
+        assertEquals("It has sources", 1, srcGroups.length);
+        assertTrue("Empty.java belongs in there", srcGroups[0].contains(emptyJava));
+
+        Lookup lkp = Lookups.fixed(javaFO);
+
+        SingleJavaSourceRunActionProvider ap = new SingleJavaSourceRunActionProvider();
+        boolean runEnabled = ap.isActionEnabled(ActionProvider.COMMAND_RUN_SINGLE, lkp);
+        assertFalse("Single File Run is disabled in Java project", runEnabled);
+        boolean debugEnabled = ap.isActionEnabled(ActionProvider.COMMAND_DEBUG_SINGLE, lkp);
+        assertFalse("Single File Debug is disabled in Java project", debugEnabled);
+    }
+
     private boolean isJDK11OrNewer() {
         return SingleSourceFileUtil.findJavaVersion() >= 11;
     }
-
 }

java/java.file.launcher/test/unit/src/org/netbeans/modules/java/file/launcher/actions/NonJavaProject.java

@@ -0,0 +1,45 @@
+/*
+ * 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.netbeans.modules.java.file.launcher.actions;
+
+import org.netbeans.api.project.Project;
+import org.netbeans.spi.project.ProjectState;
+import org.openide.filesystems.FileObject;
+import org.openide.util.Lookup;
+
+final class NonJavaProject implements Project {
+
+    private final FileObject dir;
+    private final ProjectState state;
+
+    public NonJavaProject(FileObject dir, ProjectState state) {
+        this.dir = dir;
+        this.state = state;
+    }
+
+    @Override
+    public FileObject getProjectDirectory() {
+        return dir;
+    }
+
+    @Override
+    public Lookup getLookup() {
+        return Lookup.EMPTY;
+    }
+}

java/java.file.launcher/test/unit/src/org/netbeans/modules/java/file/launcher/actions/NonJavaProjectFactory.java

@@ -0,0 +1,47 @@
+/*
+ * 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.netbeans.modules.java.file.launcher.actions;
+
+import java.io.IOException;
+import org.netbeans.api.project.Project;
+import org.netbeans.spi.project.ProjectFactory;
+import org.netbeans.spi.project.ProjectState;
+import org.openide.filesystems.FileObject;
+import org.openide.util.lookup.ServiceProvider;
+
+@ServiceProvider(service = ProjectFactory.class, position = 9999999)
+public final class NonJavaProjectFactory implements ProjectFactory {
+
+    @Override
+    public boolean isProject(FileObject projectDirectory) {
+        return Boolean.TRUE.equals(projectDirectory.getAttribute("fallback"));
+    }
+
+    @Override
+    public Project loadProject(FileObject projectDirectory, ProjectState state) throws IOException {
+        if (isProject(projectDirectory)) {
+            return new NonJavaProject(projectDirectory, state);
+        }
+        return null;
+    }
+
+    @Override
+    public void saveProject(Project project) throws IOException, ClassCastException {
+    }
+}