javax.tools
Interface JavaFileManager

All Superinterfaces:

Closeable , Flushable , OptionChecker

All Known Subinterfaces: Implementing Classes:

StandardJavaFileManager WrapperJavaFileManager

All Known Implementing Classes:

ForwardingJavaFileManager

public interface JavaFileManager
extends Closeable, Flushable, OptionChecker

File manager for tools operating on Java Programming Language source and class files. In this context, file means an abstraction of regular files and other sources of data.

When constructing new JavaFileObjects, the file manager must determine where to create them. For example, if a file manager manages regular files on a file system, it would most likely have a current/working directory to use as default location when creating or finding files. A number of hints can be provided to a file manager as to where to create files. Any file manager might choose to ignore these hints.

Some methods in this interface use class names. Such class names must be given in the Java Virtual Machine internal form of fully qualified class and interface names. For convenience '.' and '/' are interchangeable. The internal form is defined in chapter four of the Java Virtual Machine Specification .

Discussion: this means that the names "java/lang.package-info", "java/lang/package-info", "java.lang.package-info", are valid and equivalent. Compare to binary name as defined in the Java Language Specification section 13.1 "The Form of a Binary".

The case of names is significant. All names should be treated as case-sensitive. For example, some file systems have case-insensitive, case-aware file names. File objects representing such files should take care to preserve case by using File.getCanonicalFile() or similar means. If the system is not case-aware, file objects must use other means to preserve case. When constructing new JavaFileObjects, the file manager must determine where to create it. For example, if a file manager manages regular files on a file system, it would most likely have a current/working directory to use as default location when creating or finding files. This framework, however, has no concept of directories and so it is beyond its scope to define a default location. A number of hints can be provided to a file manager as to where to create files. These hints include arguments to the the getFileForOutput methods and the setLocation methods. Any file manager may choose to ignore these hints.

Relative names Some methods in this interface use class names, the name of a class must be its binary name as defined in the Java Language Specification : some methods in this interface use relative names. A relative name is a non-null, non-empty sequence of path segments separated by '/'. '.' or '..' are invalid path segments. A valid relative name must match the "path-rootless" rule of RFC 3986 , section 3.3. Informally, this should be true:

 URI. create(relativeName). normalize(). getPath().equals(relativeName) 

All methods in this interface might throw a SecurityException. The case of names is significant, see JavaFileObject for details.

An object of this interface is not required to support multi-threaded access, that is, be synchronized. However, it must support concurrent access to different file objects created by this object. All methods in this interface may throw a SecurityException if a security exception occurs.

Implementation note: a consequence of this requirement is that a trivial implementation of output to a JarOutputStream is not a sufficient implementation. That is, rather than creating a JavaFileObject that returns the JarOutputStream directly, the contents must be cached until closed and then written to the JarOutputStream.

Unless explicitly allowed, all methods in this interface might throw a NullPointerException if given a null argument.

Since:

1.6

See Also:

JavaFileObject , FileObject

Nested Class Summary
static interface	JavaFileManager.Location           Interface for locations of file objects.

Method Summary
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 JavaFileObject	getClassLoader getFileForInput ( JavaFileManager.Location String           Gets a class loader JavaFileObject for loading plug-ins from input representing the given location. specified name.
FileObject JavaFileObject	getFileForInput getFileForOutput ( JavaFileManager.Location String  location, String  classname, JavaFileObject.Kind  packageName, String  kind, JavaFileObject           Gets a file object JavaFileObject for input output representing the specified relative name class of the specified kind.
FileObject JavaFileObject	getFileForOutput getFileForOutput ( JavaFileManager.Location String  location,  filename, String  packageName,  location, String  relativeName, FileObject           Gets a file object JavaFileObject for output representing the specified relative name given file name.
Iterable < JavaFileObject	getJavaFileForInput list ( JavaFileManager.Location String  location, String  packageName, Set  className, < JavaFileObject.Kind           Gets           Lists all JavaFileObjects in a file object package.
JavaFileObject  void	getJavaFileForOutput setLocation ( JavaFileManager.Location String  location, String  className, JavaFileObject.Kind  kind, FileObject           Gets a file object           Associate the given path with the location.
boolean	handleOption ( String  current, Iterator < String           Handles one option.
boolean	hasLocation ( JavaFileManager.Location           Determines if a location is known to this file manager.
String	inferBinaryName ( JavaFileManager.Location  location, JavaFileObject           Infers a binary name of a file object based on a location.
boolean	isSameFile ( FileObject  a, FileObject           Compares two file objects and return true if they represent the same underlying object.
Iterable < JavaFileObject	list ( JavaFileManager.Location  location, String  packageName, Set < JavaFileObject.Kind           Lists all file objects matching the given criteria in the given location.

Methods inherited from interface javax.tools. OptionChecker
isSupportedOption

getClassLoader getFileForInput

 ClassLoaderJavaFileObjectgetClassLoader getFileForInput ( JavaFileManager.LocationString location)  name)
 throws IOException

Gets a class loader for loading plug-ins from the given location. For example, to load annotation processors, a Java compiler will request a class loader for the ANNOTATION_PROCESSOR_PATH location. Gets a JavaFileObject for input representing the specified name.

On case-insentive systems, this method may treat the name as case-insensitive and return a file object with a name in different case. The rationale is that the name might have been supplied by a user in a case-insentive context, for example a command line.

Parameters:

location - a location name - the name of the file

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 a JavaFileObject

Throws:

SecurityException IOException - if a class loader can not be created in the current security context - If an I/O error occurred or (optionally) if close has been called

See Also:

IllegalStateException close() - if close() has been called and this file manager cannot be reopened

list

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

Lists all file objects matching the given criteria in the given location. List file objects in "subpackages" if recurse is true. Lists all JavaFileObjects in a package. The result may only include the specified kinds of files.

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.

Parameters:

location - a location packageName - the name of the package

packageName - a package name

kinds - return objects only of these kinds

recurse - if true include "subpackages" kinds - the kinds of JavaFileObject to return

Returns:

an Iterable of file objects matching the given criteria an Iterable of all JavaFileObjects of the specified kinds in the specified package

Throws:

IOException - if an I/O error occurred, or if close() has been called and this file manager cannot be reopened - If an I/O error occurred or (optionally) if close has been called

See Also:

IllegalStateException close() - if close() has been called and this file manager cannot be reopened

inferBinaryName getFileForOutput

 StringJavaFileObjectinferBinaryName getFileForOutput ( JavaFileManager.LocationString location,
 JavaFileObject classname,
 JavaFileObject.Kind file)  kind,
 JavaFileObject sibling)
 throws IOException,
 UnsupportedOperationException,
 IllegalArgumentException

Infers a binary name of a file object based on a location. The binary name returned might not be a valid Java binary name. Gets a JavaFileObject for output representing the specified class of the specified kind.

Optionally, this file manager may consider the sibling as a hint for where to place the output. The exact semantics of this hint is unspecified. The Sun Java 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 creating class files.

Parameters:

location - a location classname - the binary name of a class as defined in the Java Language Specification

file - a file object kind - the kind of file

sibling - a JavaFileObject to be used as hint for placement; may be null

Returns:

a binary name or null the file object is not found in the given location a JavaFileObject for output

Throws:

IllegalStateException IllegalArgumentException - if close() - if sibling is not created by this file manager and is not supported by this file manager; if the location is not known to this file manager; or if the package name is not valid

UnsupportedOperationException has been called and this file manager cannot be reopened - if the specified kind is not supported

IOException - If an I/O error occurred or (optionally) if close has been called

See Also:

close() , The Java Language Specification

isSameFile getFileForOutput

boolean 
 JavaFileObjectisSameFile getFileForOutput ( FileObjectString a,
 FileObject filename,
 String b)  location,
 String pkg)
 throws IOException,
 UnsupportedOperationException,
 IllegalArgumentException

Compares two file objects and return true if they represent the same underlying object. Gets a JavaFileObject for output representing the given file name.

Optionally, this file manager may consider a number of hints to determine where to place output: location, and package. The exact semantics of these hints are unspecified. The Sun Annotation Processing Tool, apt, for example, allows annontation processors to place output in packages in either class or source output directory. Thus apt might pass a location and package when invoking this method.

Parameters:

a - a file object location - a hierarchy to be used as hint for placement; may be null

b - a file object pkg - the canonical name of a package as defined in the Java Language Specification to be used as hint for placement; may be null

filename - a file name

Returns:

true if the given file objects represent the same underlying object a JavaFileObject for output

Throws:

IllegalArgumentException - if either of the arguments were created with another file manager and this file manager does not support foreign file objects - if sibling is not created by this file manager and is not supported by this file manager; if the location is not known to this file manager; or if the package name is not valid

UnsupportedOperationException - if the specified location is not supported

IOException - If an I/O error occurred or (optionally) if close has been called

See Also:

close() , The Java Language Specification

handleOption setLocation

boolean 
void handleOption setLocation (String current,
 Iterator location,
 String< String> remaining)  path) 

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. Associate the given path with the location.

Parameters:

current - current option location - a location

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 close() has been called and this file manager cannot be reopened path - a path

hasLocation

 
boolean hasLocation ( JavaFileManager.Location location) 

Determines if a location is known to this file manager.

Parameters:

location - a location

Returns:

true if the location is known

getJavaFileForInput

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

Gets a file object for input representing the specified class of the specified kind in the given location.

Parameters:

location - a location

className - the name of a class

kind - the kind of file, must be one of SOURCE or CLASS

Returns:

a Java 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

IOException - if an I/O error occurred, or if close() has been called and this file manager cannot be reopened

IllegalStateException - if close() has been called and this file manager cannot be reopened

getJavaFileForOutput

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

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 Sun Java 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.

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 Java 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

IOException - if an I/O error occurred, or if close() has been called and this file manager cannot be reopened

IllegalStateException - close() has been called and this file manager cannot be reopened

getFileForInput

 
 FileObjectgetFileForInput ( JavaFileManager.Location location,
 String packageName,
 String relativeName)
 throws IOException

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".

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

IOException - if an I/O error occurred, or if close() has been called and this file manager cannot be reopened

IllegalStateException - if close() has been called and this file manager cannot be reopened

getFileForOutput

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

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 Sun Java 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.

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

IOException - if an I/O error occurred, or if close() has been called and this file manager cannot be reopened

IllegalStateException - if close() has been called and this file manager cannot be reopened

flush

void flush()
           throws IOException

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

Throws:

IOException - if If an I/O error occurred or (optionally) if close has been called

See Also:

close() getFileForOutput(java.lang.String, javax.tools.JavaFileObject.Kind, javax.tools.JavaFileObject) , close()

close

void close()
           throws IOException

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. This may render this file manager useless and it may, but is not required to, throw IOException on subsequent calls to all other methods.

Specified by:

close in interface Closeable

Throws:

IOException - if If an I/O error occurred

See Also:

flush()