Overview (File System API) - NetBeans API Javadoc (Current Development Version)

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File System API
org.openide.filesystems	NetBeans internally uses the concept of a virtual filesystem.

NetBeans internally uses the concept of a virtual filesystem. This module provide APIs for accessing such virtual files as well as some support classes to make writing of custom vitual filesystems easier.

What is New (see all changes)?

• Mar 12 '07 Allow modules to dynamically add/remove layer content

  Repository.getDefaultFileSystem's content can now be influenced by adding own FileSystems into global Lookup.getDefault(). This is supposed to work in a standalone mode as well as inside NetBeans Platform. The tutorial is available in the usecases section of achitecture description.

• Sep 7 '06 Added additional methods FileUtil.createData and FileUtil.createFolder that take java.io.File as a parameter.

  Added two utility methods for creation of folders and data files that take java.io.File as a parameter: public static FileObject createFolder (final File folder) throws IOException and public static FileObject createData (final File folder) throws IOException

• May 29 '06 Semantics of XMLFileSystem's methodvalue extended to also support methods that do not depend on FileSystems API at all

  XMLFileSystem's methodvalue now supports also Map attribute, so one can write factory methods that are completely independent on filesystems by creating methods like static Object methodName(Map attrs) or static Object methodName(Map attrs, String s).

• May 3 '06 Added additional method FileObject.getOutputStream that doesn't take FileLock as a parameter.

  Although newly added method FileObject.getOutputStream doesn't take FileLock as a parameter, the implementation is responsible for taking a lock before OutputStream is returned and thus FileAlreadyLockedException exception is thrown when FileObject is already locked.

• Oct 25 '05 The way how IllegalArgumentException is thrown from FileUtil.toFileObject was changed

  Because of performance reason piece of code checking whether file was properly normalized is called conditionally just in case that assertions are enabled. Then IllegalArgumentException can't be thrown if assertions are disabled.

Use Cases

public class LoginFileSystem extends MultiFileSystem {
    private static LoginFileSystem INSTANCE;
    public LoginFileSystem() {
        // let's create the filesystem empty, because the user
        // is not yet logged in
        INSTANCE = this;
    }
    public static void assignURL(URL u) throws SAXException {
        INSTANCE.setDelegates(new XMLFileSystem(u));
    }
}
      

Exported Interfaces

Implementation Details

Where are the sources for the module?

The sources for the module are in NetBeans CVS in openide/fs directory.

What do other modules need to do to declare a dependency on this one, in addition to or instead of a plain module dependency?

XXX no answer for deploy-dependencies

Read more about the implementation in the answers to architecture questions.