Interface JavaFileManager
- All Superinterfaces:
AutoCloseable
,Closeable
,Flushable
,OptionChecker
- All Known Subinterfaces:
StandardJavaFileManager
- All Known Implementing Classes:
ForwardingJavaFileManager
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.
Relative names: 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:
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.
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
- External Specifications
- See Also:
-
Nested Class Summary
Modifier and TypeInterfaceDescriptionstatic interface
Interface for locations of file objects. -
Method Summary
Modifier and TypeMethodDescriptionvoid
close()
Releases any resources opened by this file manager directly or indirectly.default boolean
contains
(JavaFileManager.Location location, FileObject fo) Determines whether or not a given file object is "contained in" a specified location.void
flush()
Flushes any resources opened for output by this file manager directly or indirectly.getClassLoader
(JavaFileManager.Location location) Returns a class loader for loading plug-ins from the given package-oriented location.getFileForInput
(JavaFileManager.Location location, String packageName, String relativeName) Returns a file object for input representing the specified relative name in the specified package in the given package-oriented location.getFileForOutput
(JavaFileManager.Location location, String packageName, String relativeName, FileObject sibling) Returns a file object for output representing the specified relative name in the specified package in the given location.default FileObject
getFileForOutputForOriginatingFiles
(JavaFileManager.Location location, String packageName, String relativeName, FileObject... originatingFiles) Returns a file object for output representing the specified relative name in the specified package in the given location.getJavaFileForInput
(JavaFileManager.Location location, String className, JavaFileObject.Kind kind) Returns a file object for input representing the specified class of the specified kind in the given package-oriented location.getJavaFileForOutput
(JavaFileManager.Location location, String className, JavaFileObject.Kind kind, FileObject sibling) Returns a file object for output representing the specified class of the specified kind in the given package-oriented location.default JavaFileObject
getJavaFileForOutputForOriginatingFiles
(JavaFileManager.Location location, String className, JavaFileObject.Kind kind, FileObject... originatingFiles) Returns a file object for output representing the specified class of the specified kind in the given package-oriented location.default JavaFileManager.Location
getLocationForModule
(JavaFileManager.Location location, String moduleName) Gets a location for a named module within a location, which may be either a module-oriented location or an output location.default JavaFileManager.Location
getLocationForModule
(JavaFileManager.Location location, JavaFileObject fo) Gets a location for the module containing a specific file to be found within a location, which may be either a module-oriented location or an output location.default <S> ServiceLoader
<S> getServiceLoader
(JavaFileManager.Location location, Class<S> service) Get a service loader for a specific service class from a 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.inferBinaryName
(JavaFileManager.Location location, JavaFileObject file) Infers a binary name of a file object based on a package-oriented location.default String
inferModuleName
(JavaFileManager.Location location) Infer the name of the module from its location, as returned bygetLocationForModule
orlistModuleLocations
.boolean
isSameFile
(FileObject a, FileObject b) Compares two file objects and returns true if they represent the same underlying object.list
(JavaFileManager.Location location, String packageName, Set<JavaFileObject.Kind> kinds, boolean recurse) Lists all file objects matching the given criteria in the given package-oriented location.default Iterable
<Set<JavaFileManager.Location>> Lists the locations for all the modules in a module-oriented location or an output location.Methods inherited from interface javax.tools.OptionChecker
isSupportedOption
-
Method Details
-
getClassLoader
Returns a class loader for loading plug-ins from the given package-oriented location. For example, to load annotation processors, a compiler will request a class loader for theANNOTATION_PROCESSOR_PATH
location.- 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:
IllegalStateException
- ifclose()
has been called and this file manager cannot be reopenedIllegalArgumentException
- if the location is a module-oriented location
-
list
Iterable<JavaFileObject> list(JavaFileManager.Location location, String packageName, Set<JavaFileObject.Kind> kinds, boolean recurse) throws IOException Lists all file objects matching the given criteria in the given package-oriented 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.- Parameters:
location
- a locationpackageName
- a package namekinds
- return objects only of these kindsrecurse
- if true include "subpackages"- Returns:
- an Iterable of file objects matching the given criteria
- Throws:
IOException
- if an I/O error occurred, or ifclose()
has been called and this file manager cannot be reopenedIllegalArgumentException
- if the location is a module-oriented locationIllegalStateException
- ifclose()
has been called and this file manager cannot be reopened
-
inferBinaryName
Infers a binary name of a file object based on a package-oriented location. The binary name returned might not be a valid binary name according to The Java Language Specification.- Parameters:
location
- a locationfile
- a file object- Returns:
- a binary name or
null
the file object is not found in the given location - Throws:
IllegalArgumentException
- if the location is a module-oriented locationIllegalStateException
- ifclose()
has been called and this file manager cannot be reopened
-
isSameFile
Compares two file objects and returns true if they represent the same underlying object.- Parameters:
a
- a file objectb
- 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
Handles one option. Ifcurrent
is an option to this file manager, it will consume any arguments to that option fromremaining
and return true, otherwise return false.- Parameters:
current
- current optionremaining
- 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 incorrectlyIllegalStateException
- ifclose()
has been called and this file manager cannot be reopened
-
hasLocation
Determines if a location is known to this file manager.- Parameters:
location
- a location- Returns:
- true if the location is known
-
getJavaFileForInput
JavaFileObject getJavaFileForInput(JavaFileManager.Location location, String className, JavaFileObject.Kind kind) throws IOException Returns a file object for input representing the specified class of the specified kind in the given package-oriented location.- Parameters:
location
- a locationclassName
- the name of a classkind
- the kind of file, must be one ofSOURCE
orCLASS
- 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, or if the location is a module-oriented locationIOException
- if an I/O error occurred, or ifclose()
has been called and this file manager cannot be reopenedIllegalStateException
- ifclose()
has been called and this file manager cannot be reopened
-
getJavaFileForOutput
JavaFileObject getJavaFileForOutput(JavaFileManager.Location location, String className, JavaFileObject.Kind kind, FileObject sibling) throws IOException Returns a file object for output representing the specified class of the specified kind in the given package-oriented 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.
- Parameters:
location
- a package-oriented locationclassName
- the name of a classkind
- the kind of file, must be one ofSOURCE
orCLASS
sibling
- a file object to be used as hint for placement; might benull
- 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, or if the location is not an output locationIOException
- if an I/O error occurred, or ifclose()
has been called and this file manager cannot be reopenedIllegalStateException
-close()
has been called and this file manager cannot be reopened
-
getJavaFileForOutputForOriginatingFiles
default JavaFileObject getJavaFileForOutputForOriginatingFiles(JavaFileManager.Location location, String className, JavaFileObject.Kind kind, FileObject... originatingFiles) throws IOException Returns a file object for output representing the specified class of the specified kind in the given package-oriented location.The provided
originatingFiles
represent files that were, in an unspecified way, used to create the content of the file created by this method. SeeoriginatingElements
inFiler.createSourceFile(java.lang.CharSequence, javax.lang.model.element.Element...)
.Elements.getFileObjectOf(javax.lang.model.element.Element)
may be used to convert theElement
s toFileObject
s.- Implementation Requirements:
- The default implementation calls
getJavaFileForOutput(javax.tools.JavaFileManager.Location, java.lang.String, javax.tools.JavaFileObject.Kind, javax.tools.FileObject)
with the first element of theoriginatingFiles
, if any, as asibling
. - Parameters:
location
- a package-oriented locationclassName
- the name of a classkind
- the kind of file, must be one ofSOURCE
orCLASS
originatingFiles
- the files which are contributing to this newly created file;null
is equivalent to emptyoriginatingFiles
, meaning no known originating files- 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, or if the location is not an output locationIOException
- if an I/O error occurred, or ifclose()
has been called and this file manager cannot be reopenedIllegalStateException
-close()
has been called and this file manager cannot be reopened- Since:
- 18
- See Also:
-
getFileForInput
FileObject getFileForInput(JavaFileManager.Location location, String packageName, String relativeName) throws IOException Returns a file object for input representing the specified relative name in the specified package in the given package-oriented 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 package-oriented locationpackageName
- a package namerelativeName
- 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 ifrelativeName
is not valid, or if the location is a module-oriented locationIOException
- if an I/O error occurred, or ifclose()
has been called and this file manager cannot be reopenedIllegalStateException
- ifclose()
has been called and this file manager cannot be reopened
-
getFileForOutput
FileObject getFileForOutput(JavaFileManager.Location location, String packageName, String relativeName, FileObject sibling) throws IOException Returns 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.- Parameters:
location
- an output locationpackageName
- a package namerelativeName
- a relative namesibling
- a file object to be used as hint for placement; might benull
- 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 ifrelativeName
is not valid, or if the location is not an output locationIOException
- if an I/O error occurred, or ifclose()
has been called and this file manager cannot be reopenedIllegalStateException
- ifclose()
has been called and this file manager cannot be reopened
-
getFileForOutputForOriginatingFiles
default FileObject getFileForOutputForOriginatingFiles(JavaFileManager.Location location, String packageName, String relativeName, FileObject... originatingFiles) throws IOException Returns a file object for output representing the specified relative name in the specified package in the given location.The provided
originatingFiles
represent files that were, in an unspecified way, used to create the content of the file created by this method. SeeoriginatingElements
inFiler.createResource(javax.tools.JavaFileManager.Location, java.lang.CharSequence, java.lang.CharSequence, javax.lang.model.element.Element...)
.Elements.getFileObjectOf(javax.lang.model.element.Element)
may be used to convert theElement
s toFileObject
s.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 in a location inferred from the
originatingFiles
. SeegetFileForInput
for an example.- Implementation Requirements:
- The default implementation calls
getFileForOutput(javax.tools.JavaFileManager.Location, java.lang.String, java.lang.String, javax.tools.FileObject)
with the first element of theoriginatingFiles
, if any, as asibling
. - Parameters:
location
- an output locationpackageName
- a package namerelativeName
- a relative nameoriginatingFiles
- the files which are contributing to this newly created file;null
is equivalent to emptyoriginatingFiles
, meaning no known originating files- 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 ifrelativeName
is not valid, or if the location is not an output locationIOException
- if an I/O error occurred, or ifclose()
has been called and this file manager cannot be reopenedIllegalStateException
- ifclose()
has been called and this file manager cannot be reopened- Since:
- 18
- See Also:
-
flush
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 interfaceFlushable
- Throws:
IOException
- if an I/O error occurred- See Also:
-
close
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 interfaceAutoCloseable
- Specified by:
close
in interfaceCloseable
- Throws:
IOException
- if an I/O error occurred- See Also:
-
getLocationForModule
default JavaFileManager.Location getLocationForModule(JavaFileManager.Location location, String moduleName) throws IOException Gets a location for a named module within a location, which may be either a module-oriented location or an output location. The result will be an output location if the given location is an output location, or it will be a package-oriented location.- Implementation Requirements:
- This implementation throws
UnsupportedOperationException
. - Parameters:
location
- the module-oriented locationmoduleName
- the name of the module to be found- Returns:
- the location for the named module
- Throws:
IOException
- if an I/O error occurredUnsupportedOperationException
- if this operation is not supported by this file managerIllegalArgumentException
- if the location is neither an output location nor a module-oriented location- Since:
- 9
-
getLocationForModule
default JavaFileManager.Location getLocationForModule(JavaFileManager.Location location, JavaFileObject fo) throws IOException Gets a location for the module containing a specific file to be found within a location, which may be either a module-oriented location or an output location. The result will be an output location if the given location is an output location, or it will be a package-oriented location.- Implementation Requirements:
- This implementation throws
UnsupportedOperationException
. - Parameters:
location
- the module-oriented locationfo
- the file- Returns:
- the module containing the file
- Throws:
IOException
- if an I/O error occurredUnsupportedOperationException
- if this operation is not supported by this file managerIllegalArgumentException
- if the location is neither an output location nor a module-oriented location- Since:
- 9
-
getServiceLoader
default <S> ServiceLoader<S> getServiceLoader(JavaFileManager.Location location, Class<S> service) throws IOException Get a service loader for a specific service class from a given location. If the location is a module-oriented location, the service loader will use the service declarations in the modules found in that location. Otherwise, a service loader is created using the package-oriented location, in which case, the services are determined using the provider-configuration files inMETA-INF/services
.- Implementation Requirements:
- This implementation throws
UnsupportedOperationException
. - Type Parameters:
S
- the service class- Parameters:
location
- the module-oriented locationservice
- theClass
object of the service class- Returns:
- a service loader for the given service class
- Throws:
IOException
- if an I/O error occurredUnsupportedOperationException
- if this operation is not supported by this file manager- Since:
- 9
-
inferModuleName
Infer the name of the module from its location, as returned bygetLocationForModule
orlistModuleLocations
.- Implementation Requirements:
- This implementation throws
UnsupportedOperationException
. - Parameters:
location
- a package-oriented location representing a module- Returns:
- the name of the module
- Throws:
IOException
- if an I/O error occurredUnsupportedOperationException
- if this operation is not supported by this file managerIllegalArgumentException
- if the location is not one known to this file manager- Since:
- 9
-
listLocationsForModules
default Iterable<Set<JavaFileManager.Location>> listLocationsForModules(JavaFileManager.Location location) throws IOException Lists the locations for all the modules in a module-oriented location or an output location. The locations that are returned will be output locations if the given location is an output, or it will be a package-oriented locations.- Implementation Requirements:
- This implementation throws
UnsupportedOperationException
. - Parameters:
location
- the module-oriented location for which to list the modules- Returns:
- a series of sets of locations containing modules
- Throws:
IOException
- if an I/O error occurredUnsupportedOperationException
- if this operation is not supported by this file managerIllegalArgumentException
- if the location is not a module-oriented location- Since:
- 9
-
contains
Determines whether or not a given file object is "contained in" a specified location.For a package-oriented location, a file object is contained in the location if there exist values for packageName and relativeName such that either of the following calls would return the
same
file object:getFileForInput(location, packageName, relativeName) getFileForOutput(location, packageName, relativeName, null)
For a module-oriented location, a file object is contained in the location if there exists a module that may be obtained by the call:
getLocationForModule(location, moduleName)
- Implementation Requirements:
- This implementation throws
UnsupportedOperationException
. - Parameters:
location
- the locationfo
- the file object- Returns:
- whether or not the file is contained in the location
- Throws:
IOException
- if there is a problem determining the resultUnsupportedOperationException
- if the method is not supported- Since:
- 9
-