Master Filesystem Valhalla compatibility

The WeakHashMap keys, which are used to track the lifecycle of
BaseFileObj, must be identity objects.

This is also a bugfix, since Integers are bad reference strength
indicators due to the internal Integer boxing cache.

Author: mbien

platform/masterfs/nbproject/project.properties

@@ -16,7 +16,7 @@
 # under the License.
 
 javac.compilerargs=-Xlint -Xlint:-serial
-javac.source=1.8
+javac.release=17
 javadoc.arch=${basedir}/arch.xml
 javadoc.apichanges=${basedir}/apichanges.xml
 

platform/masterfs/src/org/netbeans/modules/masterfs/filebasedfs/children/ChildrenSupport.java

@@ -305,7 +305,7 @@ private static Set<FileNaming> deepMinus(Set<FileNaming> base, Set<FileNaming> m
 
     private FileNaming lookupChildInCache(final FileNaming folder, final String childName, boolean lookupExisting) {
         final File f = new File(folder.getFile(), childName);
-        final Integer id = NamingFactory.createID(f);
+        final FileNaming.ID id = NamingFactory.createID(f);
 
         class FakeNaming implements FileNaming {
             public FileNaming lastEqual;
@@ -324,7 +324,7 @@ public File getFile() {
                 return f;
             }
 
-            public Integer getId() {
+            public FileNaming.ID getId() {
                 return id;
             }
             public FileNaming rename(String name, ProvidedExtensions.IOHandler h) {
@@ -346,7 +346,7 @@ public boolean equals(Object obj) {
 
             @Override
             public int hashCode() {
-                return id.intValue();
+                return id.value();
             }
 
             public boolean isFile() {

platform/masterfs/src/org/netbeans/modules/masterfs/filebasedfs/fileobjects/FileObjectFactory.java

@@ -56,10 +56,15 @@
  * @author Radek Matous
  */
 public final class FileObjectFactory {
-    public static final Map<File, FileObjectFactory> AllFactories = new HashMap<File, FileObjectFactory>();
+    public static final Map<File, FileObjectFactory> AllFactories = new HashMap<>();
     public static boolean WARNINGS = true;
+
+    // values are Reference<BaseFileObj> or List<Reference<BaseFileObj>>
+    // if a BaseFileObj is no longer strongly reachable it shall dissappear from this Map
+
     //@GuardedBy("allIBaseLock")
-    final Map<Integer, Object> allIBaseFileObjects = new WeakHashMap<Integer, Object>();
+    final Map<FileNaming.ID, Object> allIBaseFileObjects = new WeakHashMap<>();
+
     final ReadWriteLock allIBaseLock = new ReentrantReadWriteLock();
     private BaseFileObj root;
     private static final Logger LOG_REFRESH = Logger.getLogger("org.netbeans.modules.masterfs.REFRESH"); // NOI18N
@@ -604,14 +609,14 @@ public static boolean isParentOf(final File dir, final File file) {
     }
 
     public final void rename(Set<BaseFileObj> changeId) {
-        final Map<Integer, Object> toRename = new HashMap<Integer, Object>();
+        final Map<FileNaming.ID, Object> toRename = new HashMap<>();
         allIBaseLock.writeLock().lock();
         try {
-            final Iterator<Map.Entry<Integer, Object>> it = allIBaseFileObjects.entrySet().iterator();
+            final Iterator<Map.Entry<FileNaming.ID, Object>> it = allIBaseFileObjects.entrySet().iterator();
             while (it.hasNext()) {
-                Map.Entry<Integer, Object> entry = it.next();
+                Map.Entry<FileNaming.ID, Object> entry = it.next();
                 final Object obj = entry.getValue();
-                final Integer key = entry.getKey();
+                final FileNaming.ID key = entry.getKey();
                 if (!(obj instanceof List<?>)) {
                     @SuppressWarnings("unchecked")
                     final WeakReference<BaseFileObj> ref = (WeakReference<BaseFileObj>) obj;
@@ -633,8 +638,8 @@ public final void rename(Set<BaseFileObj> changeId) {
                 }
             }
 
-            for (Map.Entry<Integer, Object> entry : toRename.entrySet()) {
-                Integer key = entry.getKey();
+            for (Map.Entry<FileNaming.ID, Object> entry : toRename.entrySet()) {
+                FileNaming.ID key = entry.getKey();
                 Object previous = allIBaseFileObjects.remove(key);
                 if (previous instanceof List<?>) {
                     List<?> list = (List<?>) previous;
@@ -655,7 +660,7 @@ public final BaseFileObj getCachedOnly(final File file) {
     }
     public final BaseFileObj getCachedOnly(final File file, boolean checkExtension) {
         BaseFileObj retval;
-        final Integer id = NamingFactory.createID(file);
+        final FileNaming.ID id = NamingFactory.createID(file);
         allIBaseLock.readLock().lock();
         try {
             final Object value = allIBaseFileObjects.get(id);
@@ -698,7 +703,7 @@ private static BaseFileObj getReference(final List<?> list, final File file) {
         return retVal;
     }
 
-    private BaseFileObj putInCache(final BaseFileObj newValue, final Integer id) {
+    private BaseFileObj putInCache(final BaseFileObj newValue, final FileNaming.ID id) {
         allIBaseLock.writeLock().lock();
         try {
             final WeakReference<BaseFileObj> newRef = new WeakReference<BaseFileObj>(newValue);

platform/masterfs/src/org/netbeans/modules/masterfs/filebasedfs/naming/FileName.java

@@ -34,10 +34,10 @@
 public class FileName implements FileNaming {
     private final CharSequence name;
     private final FileNaming parent;
-    private final Integer id;
+    private final ID id;
     private CharSequence currentName;
 
-    protected FileName(final FileNaming parent, final File file, Integer theKey) {
+    protected FileName(final FileNaming parent, final File file, ID theKey) {
         this.parent = parent;
         this.name = CharSequences.create(parseName(parent, file));
         this.id = theKey == null ? NamingFactory.createID(file) : theKey;
@@ -93,7 +93,7 @@ public FileNaming rename(String name, ProvidedExtensions.IOHandler handler) thro
         return parent;
     }
 
-    public final @Override Integer getId() {
+    public final @Override ID getId() {
         return id;
     }
 
@@ -120,7 +120,7 @@ public FileNaming rename(String name, ProvidedExtensions.IOHandler handler) thro
     }
 
     public final @Override int hashCode() {
-        return id.intValue();
+        return id.value();
     }
 
     public @Override boolean isFile() {

platform/masterfs/src/org/netbeans/modules/masterfs/filebasedfs/naming/FileNaming.java

@@ -40,7 +40,15 @@ public interface FileNaming {
     boolean isFile();
     boolean isDirectory();
 
-    Integer getId();
+    ID getId();
 
     FileNaming rename(String name, ProvidedExtensions.IOHandler handler) throws IOException;
+    
+    
+    /// FileObject ID as identity object.
+    /// FileName and FileInfo objects may hold a strong reference to it, but
+    /// don't let it escape, since FileObjectFactory uses it in a WeakHashMap to track
+    /// the BaseFileObj lifecycle.
+    public record ID(int value) {}
+    
 }

platform/masterfs/src/org/netbeans/modules/masterfs/filebasedfs/naming/FolderName.java

@@ -32,7 +32,7 @@ public class FolderName extends FileName {
 
 
     @SuppressWarnings("LeakingThisInConstructor")
-    FolderName(final FileNaming parent, final File file, Integer theKey) {
+    FolderName(final FileNaming parent, final File file, ID theKey) {
         super(parent, file, theKey);
         synchronized (FolderName.class) {
             FolderName.fileCache.put(this, file);

platform/masterfs/src/org/netbeans/modules/masterfs/filebasedfs/naming/NamingFactory.java

@@ -193,8 +193,8 @@ private static void collectSubnames(FileNaming root, Collection<FileNaming> all)
         }
     }
 
-    public static Integer createID(final File file) {
-        return Utils.hashCode(file);
+    public static FileNaming.ID createID(final File file) {
+        return new FileNaming.ID(Utils.hashCode(file));
     }
     private static FileNaming registerInstanceOfFileNaming(
         FileNaming parentName, FileInfo file, FileType type,
@@ -218,8 +218,8 @@ private static void rehash(int newSize) {
                 if (fn == null) {
                     continue;
                 }
-                Integer id = createID(fn.getFile());
-                int index = Math.abs(id) % arr.length;
+                FileNaming.ID id = createID(fn.getFile());
+                int index = Math.abs(id.value()) % arr.length;
                 NameRef prev = arr[index];
                 arr[index] = nr;
                 if (prev == null) {
@@ -246,8 +246,8 @@ private static FileNaming registerInstanceOfFileNaming(
         cleanQueue();
 
         FileNaming retVal;
-        Integer key = createID(file.getFile());
-        int index = Math.abs(key) % names.length;
+        FileNaming.ID key = createID(file.getFile());
+        int index = Math.abs(key.value()) % names.length;
         NameRef ref = getReference(names[index], file.getFile());
 
         FileNaming cachedElement = (ref != null) ? ref.get() : null;
@@ -347,7 +347,7 @@ private static NameRef getReference(NameRef value, File f) {
     static enum FileType {file, directory, unknown}
 
     private static FileNaming createFileNaming(
-        final FileInfo f, Integer theKey, final FileNaming parentName, FileType type
+        final FileInfo f, FileNaming.ID theKey, final FileNaming parentName, FileType type
     ) {
         FileName retVal = null;
         //TODO: check all tests for isFile & isDirectory
@@ -370,12 +370,12 @@ private static FileNaming createFileNaming(
         return retVal;
     }
 
-    public static String dumpId(Integer id) {
-        return dump(id, null);
+    public static String dumpId(FileNaming.ID id) {
+        return dump(id.value(), null);
     }
 
     public static synchronized boolean isValid(FileNaming fn) {
-        int index = Math.abs(fn.getId()) % names.length;
+        int index = Math.abs(fn.getId().value()) % names.length;
         NameRef value = names[index];
         while (value != null) {
             if (value.get() == fn) {

platform/masterfs/src/org/netbeans/modules/masterfs/filebasedfs/utils/FileChangedManager.java

@@ -321,7 +321,7 @@ private Integer remove(int id) {
     }                
 
     private static int getKey(File f) {
-        return NamingFactory.createID(f);
+        return NamingFactory.createID(f).value();
     }
     private static int getKey(String f) {
         return getKey(new File(f));

platform/masterfs/src/org/netbeans/modules/masterfs/filebasedfs/utils/FileInfo.java

@@ -39,7 +39,7 @@ public final class FileInfo {
     private int isUNC = -1;    
     private int isConvertibleToFileObject = -1;
 
-    private Integer id = null;        
+    private FileNaming.ID id = null;        
     private FileInfo root = null;    
     private final File file;
 
@@ -190,7 +190,7 @@ public File getFile() {
         return file;
     }
 
-    public Integer getID() {
+    public FileNaming.ID getID() {
         if (id == null) {
             id = NamingFactory.createID(getFile());
         }        

platform/masterfs/test/unit/src/org/netbeans/modules/masterfs/filebasedfs/fileobjects/FileObjectFactorySizeTest.java

@@ -59,6 +59,7 @@ public void testIssuingFileObject() throws IOException {
         //root + workdir
         assertEquals(2, fbs.getSize());
         assertEquals(2, fbs.getSize());
+
         Reference<FileObject> rf = new  WeakReference<>(workDir.getParent());
         assertGC("", rf);
         assertNull(((BaseFileObj)workDir).getExistingParent());