8317128: java/nio/file/Files/CopyAndMove.java failed with AccessDeniedException

Reviewed-by: alanb, lancea

Author: Brian Burkhalter

src/java.base/share/classes/java/nio/file/CopyMoveHelper.java

@@ -25,9 +25,13 @@
 
 package java.nio.file;
 
-import java.nio.file.attribute.*;
 import java.io.InputStream;
 import java.io.IOException;
+import java.nio.file.attribute.BasicFileAttributes;
+import java.nio.file.attribute.BasicFileAttributeView;
+import java.nio.file.attribute.PosixFileAttributes;
+import java.nio.file.attribute.PosixFileAttributeView;
+import java.nio.file.spi.FileSystemProvider;
 
 /**
  * Helper class to support copying or moving files when the source and target
@@ -69,14 +73,6 @@ static CopyOptions parse(CopyOption... options) {
             }
             return result;
         }
-
-        CopyOption[] replaceExistingOrEmpty() {
-            if (replaceExisting) {
-                return new CopyOption[] { StandardCopyOption.REPLACE_EXISTING };
-            } else {
-                return new CopyOption[0];
-            }
-        }
     }
 
     /**
@@ -137,14 +133,22 @@ static void copyToForeignTarget(Path source, Path target,
         if (sourceAttrs.isSymbolicLink())
             throw new IOException("Copying of symbolic links not supported");
 
+        // ensure source can be copied
+        FileSystemProvider provider = source.getFileSystem().provider();
+        provider.checkAccess(source, AccessMode.READ);
+
+        // delete target if it exists and REPLACE_EXISTING is specified
+        if (opts.replaceExisting)
+            Files.deleteIfExists(target);
+        else if (Files.exists(target))
+            throw new FileAlreadyExistsException(target.toString());
+
         // create directory or copy file
         if (sourceAttrs.isDirectory()) {
-            if (opts.replaceExisting)
-                Files.deleteIfExists(target);
             Files.createDirectory(target);
         } else {
             try (InputStream in = Files.newInputStream(source)) {
-                Files.copy(in, target, opts.replaceExistingOrEmpty());
+                Files.copy(in, target);
             }
         }
 

src/java.base/windows/classes/sun/nio/fs/WindowsException.java

@@ -1,5 +1,5 @@
 /*
- * Copyright (c) 2008, 2016, Oracle and/or its affiliates. All rights reserved.
+ * Copyright (c) 2008, 2023, Oracle and/or its affiliates. All rights reserved.
  * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
  *
  * This code is free software; you can redistribute it and/or modify it
@@ -31,7 +31,7 @@
 import static sun.nio.fs.WindowsConstants.*;
 
 /**
- * Internal exception thrown when a Win32 calls fails.
+ * Internal exception thrown when a Win32 call fails.
  */
 
 class WindowsException extends Exception {