ForwardingJavaFileManager (Java Platform SE 8 )
Keywords: javax.tools.ForwardingJavaFileManager class
Date: 2026-03-16

compact3
javax.tools

## Class ForwardingJavaFileManager<M extends JavaFileManager>

- java.lang.Object
- - javax.tools.ForwardingJavaFileManager<M>

- Type Parameters:
    `M` - the kind of file manager forwarded to by this object
  All Implemented Interfaces:
    Closeable, Flushable, AutoCloseable, JavaFileManager, OptionChecker

      public class ForwardingJavaFileManager<M extends JavaFileManager>
      extends Object
      implements JavaFileManager

  Forwards calls to a given file manager. Subclasses of this class might override some of these methods and might also provide additional fields and methods.
  Since:
    1.6

- - ### Nested Class Summary

    - ### Nested classes/interfaces inherited from interface javax.tools.JavaFileManager

      `JavaFileManager.Location`

  - ### Field Summary

    Fields
    Modifier and Type | Field and Description
    --- | ---
    `protected M` | `fileManager` The file manager which all methods are delegated to.

  - ### Constructor Summary

    Constructors
    Modifier | Constructor and Description
    --- | ---
    `protected` | `ForwardingJavaFileManager(M fileManager)` Creates a new instance of ForwardingJavaFileManager.

  - ### Method Summary

    All Methods Instance Methods Concrete Methods
    Modifier and Type | Method and Description
    --- | ---
    `void` | `close()` Releases any resources opened by this file manager directly or indirectly.
    `void` | `flush()` Flushes any resources opened for output by this file manager directly or indirectly.
    `ClassLoader` | `getClassLoader(JavaFileManager.Location location)` Gets a class loader for loading plug-ins from the given location.
    `FileObject` | `getFileForInput(JavaFileManager.Location location, String packageName, String relativeName)` Gets a file object for input representing the specified relative name in the specified package in the given location.
    `FileObject` | `getFileForOutput(JavaFileManager.Location location, String packageName, String relativeName, FileObject sibling)` Gets a file object for output representing the specified relative name in the specified package in the given location.
    `JavaFileObject` | `getJavaFileForInput(JavaFileManager.Location location, String className, JavaFileObject.Kind kind)` Gets a file object for input representing the specified class of the specified kind in the given location.
    `JavaFileObject` | `getJavaFileForOutput(JavaFileManager.Location location, String className, JavaFileObject.Kind kind, FileObject sibling)` Gets a file object for output representing the specified class of the specified kind in the given location.
    `boolean` | `handleOption(String current, Iterator<String> remaining)` Handles one option.
    `boolean` | `hasLocation(JavaFileManager.Location location)` Determines if a location is known to this file manager.
    `String` | `inferBinaryName(JavaFileManager.Location location, JavaFileObject file)` Infers a binary name of a file object based on a location.
    `boolean` | `isSameFile(FileObject a, FileObject b)` Compares two file objects and return true if they represent the same underlying object.
    `int` | `isSupportedOption(String option)` Determines if the given option is supported and if so, the number of arguments the option takes.
    `Iterable<JavaFileObject>` | `list(JavaFileManager.Location location, String packageName, Set<JavaFileObject.Kind> kinds, boolean recurse)` Lists all file objects matching the given criteria in the given location.

    - ### Methods inherited from class java.lang.Object

      `clone, equals, finalize, getClass, hashCode, notify, notifyAll, toString, wait, wait, wait`

- - ### Field Detail

    - #### fileManager

          protected final M extends JavaFileManager fileManager

      The file manager which all methods are delegated to.

  - ### Constructor Detail

    - #### ForwardingJavaFileManager

          protected ForwardingJavaFileManager(M fileManager)

      Creates a new instance of ForwardingJavaFileManager.
      Parameters:
        `fileManager` - delegate to this file manager

  - ### Method Detail

    - #### getClassLoader

          public ClassLoader getClassLoader(JavaFileManager.Location location)

      Description copied from interface: `JavaFileManager`
      Gets a class loader for loading plug-ins from the given location. For example, to load annotation processors, a compiler will request a class loader for the `ANNOTATION_PROCESSOR_PATH` location.
      Specified by:
        `getClassLoader` in interface `JavaFileManager`
      Parameters:
        `location` - a location
      Returns:
        a class loader for the given location; or `null` if loading plug-ins from the given location is disabled or if the location is not known
      Throws:
        `SecurityException` - if a class loader can not be created in the current security context
        `IllegalStateException` - if `JavaFileManager.close()` has been called and this file manager cannot be reopened

    - #### list

          public Iterable<JavaFileObject> list(JavaFileManager.Location location,
                                               String packageName,
                                               Set<JavaFileObject.Kind> kinds,
                                               boolean recurse)
                                        throws IOException

      Description copied from interface: `JavaFileManager`
      Lists all file objects matching the given criteria in the given location. List file objects in "subpackages" if recurse is true.

      Note: even if the given location is unknown to this file manager, it may not return `null`. Also, an unknown location may not cause an exception.

      Specified by:
        `list` in interface `JavaFileManager`
      Parameters:
        `location` - a location
        `packageName` - a package name
        `kinds` - return objects only of these kinds
        `recurse` - if true include "subpackages"
      Returns:
        an Iterable of file objects matching the given criteria
      Throws:
        `IOException` - if an I/O error occurred, or if `JavaFileManager.close()` has been called and this file manager cannot be reopened
        `IllegalStateException` - if `JavaFileManager.close()` has been called and this file manager cannot be reopened

    - #### inferBinaryName

          public String inferBinaryName(JavaFileManager.Location location,
                                        JavaFileObject file)

      Description copied from interface: `JavaFileManager`
      Infers a binary name of a file object based on a location. The binary name returned might not be a valid binary name according to The Java™ Language Specification.
      Specified by:
        `inferBinaryName` in interface `JavaFileManager`
      Parameters:
        `location` - a location
        `file` - a file object
      Returns:
        a binary name or `null` the file object is not found in the given location
      Throws:
        `IllegalStateException` - if `JavaFileManager.close()` has been called and this file manager cannot be reopened

    - #### isSameFile

          public boolean isSameFile(FileObject a,
                                    FileObject b)

      Description copied from interface: `JavaFileManager`
      Compares two file objects and return true if they represent the same underlying object.
      Specified by:
        `isSameFile` in interface `JavaFileManager`
      Parameters:
        `a` - a file object
        `b` - a file object
      Returns:
        true if the given file objects represent the same underlying object
      Throws:
        `IllegalArgumentException` - if either of the arguments were created with another file manager and this file manager does not support foreign file objects

    - #### handleOption

          public boolean handleOption(String current,
                                      Iterator<String> remaining)

      Description copied from interface: `JavaFileManager`
      Handles one option. If `current` is an option to this file manager it will consume any arguments to that option from `remaining` and return true, otherwise return false.
      Specified by:
        `handleOption` in interface `JavaFileManager`
      Parameters:
        `current` - current option
        `remaining` - remaining options
      Returns:
        true if this option was handled by this file manager, false otherwise
      Throws:
        `IllegalArgumentException` - if this option to this file manager is used incorrectly
        `IllegalStateException` - if `JavaFileManager.close()` has been called and this file manager cannot be reopened

    - #### hasLocation

          public boolean hasLocation(JavaFileManager.Location location)

      Description copied from interface: `JavaFileManager`
      Determines if a location is known to this file manager.
      Specified by:
        `hasLocation` in interface `JavaFileManager`
      Parameters:
        `location` - a location
      Returns:
        true if the location is known

    - #### isSupportedOption

          public int isSupportedOption(String option)

      Description copied from interface: `OptionChecker`
      Determines if the given option is supported and if so, the number of arguments the option takes.
      Specified by:
        `isSupportedOption` in interface `OptionChecker`
      Parameters:
        `option` - an option
      Returns:
        the number of arguments the given option takes or -1 if the option is not supported

    - #### getJavaFileForInput

          public JavaFileObject getJavaFileForInput(JavaFileManager.Location location,
                                                    String className,
                                                    JavaFileObject.Kind kind)
                                             throws IOException

      Description copied from interface: `JavaFileManager`
      Gets a file object for input representing the specified class of the specified kind in the given location.
      Specified by:
        `getJavaFileForInput` in interface `JavaFileManager`
      Parameters:
        `location` - a location
        `className` - the name of a class
        `kind` - the kind of file, must be one of `SOURCE` or `CLASS`
      Returns:
        a file object, might return `null` if the file does not exist
      Throws:
        `IllegalArgumentException` - if the location is not known to this file manager and the file manager does not support unknown locations, or if the kind is not valid
        `IllegalStateException` - if `JavaFileManager.close()` has been called and this file manager cannot be reopened
        `IOException` - if an I/O error occurred, or if `JavaFileManager.close()` has been called and this file manager cannot be reopened

    - #### getJavaFileForOutput

          public JavaFileObject getJavaFileForOutput(JavaFileManager.Location location,
                                                     String className,
                                                     JavaFileObject.Kind kind,
                                                     FileObject sibling)
                                              throws IOException

      Description copied from interface: `JavaFileManager`
      Gets a file object for output representing the specified class of the specified kind in the given location.

      Optionally, this file manager might consider the sibling as a hint for where to place the output. The exact semantics of this hint is unspecified. The JDK compiler, javac, for example, will place class files in the same directories as originating source files unless a class file output directory is provided. To facilitate this behavior, javac might provide the originating source file as sibling when calling this method.

      Specified by:
        `getJavaFileForOutput` in interface `JavaFileManager`
      Parameters:
        `location` - a location
        `className` - the name of a class
        `kind` - the kind of file, must be one of `SOURCE` or `CLASS`
        `sibling` - a file object to be used as hint for placement; might be `null`
      Returns:
        a file object for output
      Throws:
        `IllegalArgumentException` - if sibling is not known to this file manager, or if the location is not known to this file manager and the file manager does not support unknown locations, or if the kind is not valid
        `IllegalStateException` - `JavaFileManager.close()` has been called and this file manager cannot be reopened
        `IOException` - if an I/O error occurred, or if `JavaFileManager.close()` has been called and this file manager cannot be reopened

    - #### getFileForInput

          public FileObject getFileForInput(JavaFileManager.Location location,
                                            String packageName,
                                            String relativeName)
                                     throws IOException

      Description copied from interface: `JavaFileManager`
      Gets a file object for input representing the specified relative name in the specified package in the given location.

      If the returned object represents a source or class file, it must be an instance of `JavaFileObject`.

      Informally, the file object returned by this method is located in the concatenation of the location, package name, and relative name. For example, to locate the properties file "resources/compiler.properties" in the package "com.sun.tools.javac" in the SOURCE_PATH location, this method might be called like so:

          getFileForInput(SOURCE_PATH, "com.sun.tools.javac", "resources/compiler.properties");

      If the call was executed on Windows, with SOURCE_PATH set to `"C:\Documents and Settings\UncleBob\src\share\classes"`, a valid result would be a file object representing the file `"C:\Documents and Settings\UncleBob\src\share\classes\com\sun\tools\javac\resources\compiler.properties"`.

      Specified by:
        `getFileForInput` in interface `JavaFileManager`
      Parameters:
        `location` - a location
        `packageName` - a package name
        `relativeName` - a relative name
      Returns:
        a file object, might return `null` if the file does not exist
      Throws:
        `IllegalArgumentException` - if the location is not known to this file manager and the file manager does not support unknown locations, or if `relativeName` is not valid
        `IllegalStateException` - if `JavaFileManager.close()` has been called and this file manager cannot be reopened
        `IOException` - if an I/O error occurred, or if `JavaFileManager.close()` has been called and this file manager cannot be reopened

    - #### getFileForOutput

          public FileObject getFileForOutput(JavaFileManager.Location location,
                                             String packageName,
                                             String relativeName,
                                             FileObject sibling)
                                      throws IOException

      Description copied from interface: `JavaFileManager`
      Gets a file object for output representing the specified relative name in the specified package in the given location.

      Optionally, this file manager might consider the sibling as a hint for where to place the output. The exact semantics of this hint is unspecified. The JDK compiler, javac, for example, will place class files in the same directories as originating source files unless a class file output directory is provided. To facilitate this behavior, javac might provide the originating source file as sibling when calling this method.

      If the returned object represents a source or class file, it must be an instance of `JavaFileObject`.

      Informally, the file object returned by this method is located in the concatenation of the location, package name, and relative name or next to the sibling argument. See `getFileForInput` for an example.

      Specified by:
        `getFileForOutput` in interface `JavaFileManager`
      Parameters:
        `location` - a location
        `packageName` - a package name
        `relativeName` - a relative name
        `sibling` - a file object to be used as hint for placement; might be `null`
      Returns:
        a file object
      Throws:
        `IllegalArgumentException` - if sibling is not known to this file manager, or if the location is not known to this file manager and the file manager does not support unknown locations, or if `relativeName` is not valid
        `IllegalStateException` - if `JavaFileManager.close()` has been called and this file manager cannot be reopened
        `IOException` - if an I/O error occurred, or if `JavaFileManager.close()` has been called and this file manager cannot be reopened

    - #### flush

          public void flush()
                     throws IOException

      Description copied from interface: `JavaFileManager`
      Flushes any resources opened for output by this file manager directly or indirectly. Flushing a closed file manager has no effect.
      Specified by:
        `flush` in interface `Flushable`
      Specified by:
        `flush` in interface `JavaFileManager`
      Throws:
        `IOException` - if an I/O error occurred
      See Also:
        `JavaFileManager.close()`

    - #### close

          public void close()
                     throws IOException

      Description copied from interface: `JavaFileManager`
      Releases any resources opened by this file manager directly or indirectly. This might render this file manager useless and the effect of subsequent calls to methods on this object or any objects obtained through this object is undefined unless explicitly allowed. However, closing a file manager which has already been closed has no effect.
      Specified by:
        `close` in interface `Closeable`
      Specified by:
        `close` in interface `AutoCloseable`
      Specified by:
        `close` in interface `JavaFileManager`
      Throws:
        `IOException` - if an I/O error occurred
      See Also:
        `JavaFileManager.flush()`

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