javax.tools.JavaCompilerTool.getStandardFileManager().list() treats directories as package, if path is relative and if the path is absolute list will not give any thing. Rather it should throw IllegalArgumentException

Test case :
<testcase>
public class T6351767 {
    public static void main(String... args) throws Exception {

        // Createing necessary things.....
        File dir = new File("temp"+args.hashCode());
        if (!dir.exists())
            dir.mkdir();
        if (!dir.isDirectory())
            throw new AssertionError("Not a directory " + dir);

        File dir1 = new File(dir.getPath()+"/temp"+args.hashCode());
        if (!dir1.exists())
            dir1.mkdir();
        if (!dir1.isDirectory())
            throw new AssertionError("Not a directory " + dir);

        File dir2 = new File(dir1.getPath()+"/File1.java");
        if (!dir2.exists())
            dir2.createNewFile();
        if (!dir2.isFile())
            throw new AssertionError("Not a file" + dir);


        // Main Code
        try {
            JavaCompilerTool compiler = ToolProvider.defaultJavaCompiler();
            JavaFileManager jfm = compiler.getStandardFileManager();

            for (JavaFileObject jfo : jfm.list(dir1.getPath(), EnumSet.of(Kind.SOURCE))) {
                        if(jfo.getName().equals("File1.java"))
                                throw new AssertionError("Getting files from directory :"+jfo);
            }
        } finally {
                dir2.delete();
            dir1.delete(); // cleanup
            dir.delete();
        }

    }
}

</testcase>

Tried in SunOS 5.10 sparc Ultra-60
<java-version>
java version "1.6.0-rc"
Java(TM) 2 Runtime Environment, Standard Edition (build 1.6.0-rc-b60)
Java HotSpot(TM) Client VM (build 1.6.0-rc-b60, mixed mode)
</java-version>