core: Make Inode a subclass of FileHandle; deprecate constructors

In an effort to simplify file handle/inode call, make Inode no longer
encapsulate FileHandle, but extend from it.

While the ultimate goal is to deprecate FileHandle, and allow Inode to
be used directly in more places, this is the first step in a series of
changes.

Deprecate the direct use of Inode constructors in favor of static helper
methods.

Adjust some places in the code that assumed encapsulation / called
constructors directly.

Related: #149
Signed-off-by: Christian Kohlschütter <[email protected]>

Author: kohlschuetter

core/src/main/java/org/dcache/nfs/vfs/FileHandle.java

@@ -201,6 +201,10 @@ public FileHandle build(byte[] opaque) {
             return new FileHandle(generation, export_idx, type, opaque);
         }
 
+        public Inode buildInode(byte[] opaque) {
+            return new Inode(generation, export_idx, type, opaque);
+        }
+
         public FileHandle build() {
             return build(fs_opaque);
         }

core/src/main/java/org/dcache/nfs/vfs/Inode.java

@@ -21,33 +21,52 @@
 
 import java.util.Arrays;
 
-public class Inode {
+public class Inode extends FileHandle {
+    /**
+     * This constructor will become marked {@code protected} in a future version.
+     *
+     * @param bytes The VFS-specific bytes.
+     */
+    @Deprecated
+    public Inode(byte[] bytes) {
+        super(bytes);
+    }
 
-    private final FileHandle fh;
+    @Deprecated(forRemoval = true)
+    public Inode(FileHandle fh) {
+        this(fh.bytes());
+    }
 
-    public Inode(byte[] bytes) {
-        this(new FileHandle(bytes));
+    Inode(int generation, int exportIdx, int type, byte[] fs_opaque) {
+        super(generation, exportIdx, type, fs_opaque);
+    }
+
+    public static Inode forFileHandle(FileHandle fh) {
+        if (fh instanceof Inode) {
+            return ((Inode) fh);
+        }
+        return new Inode(fh.bytes());
     }
 
-    public Inode(FileHandle h) {
-        fh = h;
+    public static Inode forNfsHandle(byte[] bytes) {
+        return new Inode(bytes);
     }
 
     public static Inode forFile(byte[] bytes) {
-        return new Inode(new FileHandle.FileHandleBuilder().build(bytes));
+        return new FileHandle.FileHandleBuilder().buildInode(bytes);
     }
 
     public byte[] getFileId() {
-        return fh.getFsOpaque();
+        return getFsOpaque();
     }
 
     public byte[] toNfsHandle() {
-        return fh.bytes();
+        return bytes();
     }
 
     @Override
     public int hashCode() {
-        return Arrays.hashCode(fh.bytes());
+        return Arrays.hashCode(bytes());
     }
 
     @Override
@@ -59,23 +78,18 @@ public boolean equals(Object obj) {
             return false;
         }
         final Inode other = (Inode) obj;
-        return Arrays.equals(fh.bytes(), other.fh.bytes());
+        return Arrays.equals(bytes(), other.bytes());
     }
 
     public boolean isPseudoInode() {
-        return fh.getType() == 1;
+        return getType() == 1;
     }
 
     public int exportIndex() {
-        return fh.getExportIdx();
+        return getExportIdx();
     }
 
     public int handleVersion() {
-        return fh.getVersion();
-    }
-
-    @Override
-    public String toString() {
-        return fh.toString();
+        return getVersion();
     }
 }

core/src/main/java/org/dcache/nfs/vfs/PseudoFs.java

@@ -547,7 +547,7 @@ public static Inode pseudoIdToReal(Inode inode, int index) {
                 .setExportIdx(index)
                 .setType(0)
                 .build(inode.getFileId());
-        return new Inode(fh);
+        return Inode.forFileHandle(fh);
     }
 
     private int getIndexId(PseudoFsNode node) {
@@ -618,7 +618,7 @@ private Inode pushExportIndex(Inode inode, int index) {
                 .setExportIdx(index)
                 .setType(0)
                 .build(inode.getFileId());
-        return new Inode(fh);
+        return Inode.forFileHandle(fh);
     }
 
     private Inode pushExportIndex(Inode parent, Inode inode) {
@@ -648,7 +648,7 @@ private Inode realToPseudo(Inode inode, int idx) {
                 .setExportIdx(idx)
                 .setType(1)
                 .build(inode.getFileId());
-        return new Inode(fh);
+        return Inode.forFileHandle(fh);
     }
 
     private void pathToPseudoFs(final PseudoFsNode root, Set<PseudoFsNode> all, FsExport e) {

core/src/main/java/org/dcache/nfs/vfs/VirtualFileSystem.java

@@ -520,4 +520,15 @@ default void removeXattr(Inode inode, String attr) throws IOException {
     default CompletableFuture<Long> copyFileRange(Inode src, long srcPos, Inode dst, long dstPos, long len) {
         return CompletableFuture.failedFuture(new NotSuppException());
     }
+
+    /**
+     * Converts an NFS file handle to an {@link Inode}.
+     * 
+     * @param bytes The NFS file handle.
+     * @return The {@link Inode}; must not be {@code null}.
+     * @throws IOException on error
+     */
+    default Inode inodeForNfsHandle(byte[] bytes) throws IOException {
+        return Inode.forNfsHandle(bytes);
+    }
 }

core/src/test/java/org/dcache/nfs/v3/NfsServerV3READDIRPLUS_3Test.java

@@ -42,7 +42,7 @@ public class NfsServerV3READDIRPLUS_3Test {
     @Before
     public void setup() throws Exception {
         dirHandle = new FileHandle(0, 1, 0, new byte[] {0, 0, 0, 1}); // the dir we want to read
-        dirInode = new Inode(dirHandle);
+        dirInode = Inode.forFileHandle(dirHandle);
         dirStat = new Stat(); // the stat marking it as a dir
         // noinspection OctalInteger
         dirStat.setMode(Stat.S_IFDIR | 0755);

core/src/test/java/org/dcache/nfs/v3/NfsServerV3READDIR_3Test.java

@@ -43,7 +43,7 @@ public class NfsServerV3READDIR_3Test {
     @Before
     public void setup() throws Exception {
         dirHandle = new FileHandle(0, 1, 0, new byte[] {0, 0, 0, 1}); // the dir we want to read
-        dirInode = new Inode(dirHandle);
+        dirInode = Inode.forFileHandle(dirHandle);
         dirStat = new Stat(); // the stat marking it as a dir
         // noinspection OctalInteger
         dirStat.setMode(Stat.S_IFDIR | 0755);

core/src/test/java/org/dcache/nfs/v4/OperationREADDIRTest.java

@@ -61,7 +61,7 @@ public class OperationREADDIRTest {
     @Before
     public void setup() throws Exception {
         dirHandle = new FileHandle(0, 0, 0, new byte[] {0, 0, 0, 0}); // the dir we want to read
-        dirInode = new Inode(dirHandle);
+        dirInode = Inode.forFileHandle(dirHandle);
         dirStat = new Stat(); // the stat marking it as a dir
         // noinspection OctalInteger
         dirStat.setMode(Stat.S_IFDIR | 0755);
@@ -174,7 +174,7 @@ private DirectoryEntry dir(String name) {
         int cookie = ino++;
 
         FileHandle handle = new FileHandle(0, 1, 0, Ints.toByteArray(cookie));
-        Inode inode = new Inode(handle);
+        Inode inode = Inode.forFileHandle(handle);
         Stat stat = new Stat(); // the stat marking it as a dir
         // noinspection OctalInteger
         stat.setMode(Stat.S_IFDIR | 0755);
@@ -202,7 +202,7 @@ private DirectoryEntry file(String name) {
         int cookie = ino++;
 
         FileHandle handle = new FileHandle(0, 1, 0, Ints.toByteArray(cookie));
-        Inode inode = new Inode(handle);
+        Inode inode = Inode.forFileHandle(handle);
         Stat stat = new Stat(); // the stat marking it as a dir
         // noinspection OctalInteger
         stat.setMode(Stat.S_IFREG | 0644);

core/src/test/java/org/dcache/nfs/vfs/DirectoryStreamTest.java

@@ -26,7 +26,7 @@ public void setUp() {
 
         for (int i = 0; i < 10; i++) {
             FileHandle fh = new FileHandle(0, 0, 0, Ints.toByteArray(i));
-            Inode inode = new Inode(fh);
+            Inode inode = Inode.forFileHandle(fh);
             Stat stat = new Stat();
 
             stat.setMode(Stat.S_IFDIR | 0755);

core/src/test/java/org/dcache/nfs/vfs/PseudoFsTest.java

@@ -384,10 +384,9 @@ public void testAccessDenyOnHighjackedInode() throws IOException {
         given(mockedRpc.getTransport()).willReturn(mockedTransport);
         given(mockedRpc.getCredential()).willReturn(mockedAuth);
 
-        Inode inode = new Inode(
-                new FileHandle.FileHandleBuilder()
+        Inode inode = new FileHandle.FileHandleBuilder()
                         .setExportIdx(1)
-                        .build(Longs.toByteArray(1L)));
+                        .buildInode(Longs.toByteArray(1L));
 
         given(mockedExportFile.getExport(1, localAddress.getAddress())).willReturn(null);