Method Summary

Method Details

• isNamed

  public boolean isNamed()

  Returnstrue if this module is a named module.

  Returns:

  true if this is a named module

  SeeJava Language Specification:

  7.7.5 Unnamed Modules
  

  See Also:

  • ClassLoader.getUnnamedModule()

• getName

  public String getName()

  Returns the module name ornull if this module is an unnamed module.

  Returns:

  The module name

• getClassLoader

  public ClassLoader getClassLoader()

  Returns theClassLoader for this module.

  If there is a security manager then itscheckPermission method if first called with aRuntimePermission("getClassLoader") permission to check that the caller is allowed to get access to the class loader.

  Returns:

  The class loader for this module

  Throws:

  SecurityException - If denied by the security manager

• getDescriptor

  public ModuleDescriptor getDescriptor()

  Returns the module descriptor for this module ornull if this module is an unnamed module.

  Returns:

  The module descriptor for this module

• getLayer

  public ModuleLayer getLayer()

  Returns the module layer that contains this module ornull if this module is not in a module layer. A module layer contains named modules and therefore this method always returnsnull when invoked on an unnamed module.

  Dynamic modules are named modules that are generated at runtime. A dynamic module may or may not be in a module layer.

  Returns:

  The module layer that contains this module

  See Also:

  • Proxy

• isNativeAccessEnabled

  public boolean isNativeAccessEnabled()

  Returnstrue if this module can accessrestricted methods.

  Returns:

  true if this module can accessrestricted methods.

  Since:

  22

• canRead

  public boolean canRead(Module other)

  Indicates if this module reads the given module. This method returnstrue if invoked to test if this module reads itself. It also returnstrue if invoked on an unnamed module (as unnamed modules read all modules).

  Parameters:

  other - The other module

  Returns:

  true if this module readsother

  See Also:

  • addReads(Module)

• addReads

  public Module addReads(Module other)

  If the caller's module is this module then update this module to read the given module. This method is a no-op ifother is this module (all modules read themselves), this module is an unnamed module (as unnamed modules read all modules), or this module already readsother.

  Implementation Note:

  Read edges added by this method areweak and do not preventother from being GC'ed when this module is strongly reachable.

  Parameters:

  other - The other module

  Returns:

  this module

  Throws:

  IllegalCallerException - If this is a named module and the caller's module is not this module

  See Also:

  • canRead(java.lang.Module)

• isExported

  public boolean isExported(String pn,Module other)

  Returnstrue if this module exports the given package to at least the given module.

  This method returnstrue if invoked to test if a package in this module is exported to itself. It always returnstrue when invoked on an unnamed module. A package that isopen to the given module is considered exported to that module at run-time and so this method returnstrue if the package is open to the given module.

  This method does not check if the given module reads this module.

  Parameters:

  pn - The package name

  other - The other module

  Returns:

  true if this module exports the package to at least the given module

  See Also:

  • ModuleDescriptor.exports()
  • addExports(String,Module)

• isOpen

  public boolean isOpen(String pn,Module other)

  Returnstrue if this module hasopened a package to at least the given module.

  This method returnstrue if invoked to test if a package in this module is open to itself. It returnstrue when invoked on anopen module with a package in the module. It always returnstrue when invoked on an unnamed module.

  This method does not check if the given module reads this module.

  API Note:

  A packagep opened to moduleM allows code inM dodeep reflection on all types in the package. Further, ifM reads this module, it can obtain aLookup object that is allowed todefine classes in packagep.

  Parameters:

  pn - The package name

  other - The other module

  Returns:

  true if this module hasopened the package to at least the given module

  See Also:

  • ModuleDescriptor.opens()
  • addOpens(String,Module)
  • AccessibleObject.setAccessible(boolean)
  • MethodHandles.privateLookupIn(java.lang.Class<?>, java.lang.invoke.MethodHandles.Lookup)

• isExported

  public boolean isExported(String pn)

  Returnstrue if this module exports the given package unconditionally.

  This method always returnstrue when invoked on an unnamed module. A package that isopened unconditionally is considered exported unconditionally at run-time and so this method returnstrue if the package is opened unconditionally.

  This method does not check if the given module reads this module.

  Parameters:

  pn - The package name

  Returns:

  true if this module exports the package unconditionally

  See Also:

  • ModuleDescriptor.exports()

• isOpen

  public boolean isOpen(String pn)

  Returnstrue if this module hasopened a package unconditionally.

  This method always returnstrue when invoked on an unnamed module. Additionally, it always returnstrue when invoked on anopen module with a package in the module.

  This method does not check if the given module reads this module.

  API Note:

  A packagep opened to moduleM allows code inM dodeep reflection on all types in the package. Further, ifM reads this module, it can obtain aLookup object that is allowed todefine classes in packagep.

  Parameters:

  pn - The package name

  Returns:

  true if this module hasopened the package unconditionally

  See Also:

  • ModuleDescriptor.opens()
  • AccessibleObject.setAccessible(boolean)
  • MethodHandles.privateLookupIn(java.lang.Class<?>, java.lang.invoke.MethodHandles.Lookup)

• addExports

  public Module addExports(String pn,Module other)

  If the caller's module is this module then update this module to export the given package to the given module.

  This method has no effect if the package is already exported (oropen) to the given module.

  API Note:

  As specified in section5.4.3 of theThe Java Virtual Machine Specification, if an attempt to resolve a symbolic reference fails because of a linkage error, then subsequent attempts to resolve the reference always fail with the same error that was thrown as a result of the initial resolution attempt.

  Parameters:

  pn - The package name

  other - The module

  Returns:

  this module

  Throws:

  IllegalArgumentException - Ifpn isnull, or this is a named module and the packagepn is not a package in this module

  IllegalCallerException - If this is a named module and the caller's module is not this module

  SeeJava Virtual Machine Specification:

  5.4.3 Resolution
  

  See Also:

  • isExported(String,Module)

• addOpens

  public Module addOpens(String pn,Module other)

  If this module hasopened a package to at least the caller module then update this module to open the package to the given module. Opening a package with this method allows all types in the package, and all their members, not just public types and their public members, to be reflected on by the given module when using APIs that support private access or a way to bypass or suppress default Java language access control checks.

  This method has no effect if the package is alreadyopen to the given module.

  API Note:

  This method can be used for cases where aconsumer module uses a qualified opens to open a package to anAPI module but where the reflective access to the members of classes in the consumer module is delegated to code in another module. Code in the API module can use this method to open the package in the consumer module to the other module.

  Parameters:

  pn - The package name

  other - The module

  Returns:

  this module

  Throws:

  IllegalArgumentException - Ifpn isnull, or this is a named module and the packagepn is not a package in this module

  IllegalCallerException - If this is a named module and this module has not opened the package to at least the caller's module

  See Also:

  • isOpen(String,Module)
  • AccessibleObject.setAccessible(boolean)
  • MethodHandles.privateLookupIn(java.lang.Class<?>, java.lang.invoke.MethodHandles.Lookup)

• addUses

  public Module addUses(Class<?> service)

  If the caller's module is this module then update this module to add a service dependence on the given service type. This method is intended for use by frameworks that invokeServiceLoader on behalf of other modules or where the framework is passed a reference to the service type by other code. This method is a no-op when invoked on an unnamed module or an automatic module.

  This method does not causeresolveAndBind to be re-run.

  Parameters:

  service - The service type

  Returns:

  this module

  Throws:

  IllegalCallerException - If this is a named module and the caller's module is not this module

  See Also:

  • canUse(Class)
  • ModuleDescriptor.uses()

• canUse

  public boolean canUse(Class<?> service)

  Indicates if this module has a service dependence on the given service type. This method always returnstrue when invoked on an unnamed module or an automatic module.

  Parameters:

  service - The service type

  Returns:

  true if this module uses service typest

  See Also:

  • addUses(Class)

• getPackages

  public Set<String> getPackages()

  Returns the set of package names for the packages in this module.

  For named modules, the returned set contains an element for each package in the module.

  For unnamed modules, the returned set contains an element for each package thathas been defined in the unnamed module.

  Returns:

  the set of the package names of the packages in this module

• getAnnotation

  public <T extendsAnnotation> T getAnnotation(Class<T> annotationClass)

  Returns this element's annotation for the specified type if such an annotation ispresent, else null. This method returnsnull when invoked on an unnamed module.

  Note that any annotation returned by this method is a declaration annotation.

  Specified by:

  getAnnotation in interface AnnotatedElement

  Type Parameters:

  T - the type of the annotation to query for and return if present

  Parameters:

  annotationClass - the Class object corresponding to the annotation type

  Returns:

  this element's annotation for the specified annotation type if present on this element, else null

• getAnnotations

  public Annotation[] getAnnotations()

  Returns annotations that arepresent on this element. If there are no annotationspresent on this element, the return value is an array of length 0. The caller of this method is free to modify the returned array; it will have no effect on the arrays returned to other callers. This method returns an empty array when invoked on an unnamed module.

  Note that any annotations returned by this method are declaration annotations.

  Specified by:

  getAnnotations in interface AnnotatedElement

  Returns:

  annotations present on this element

• getDeclaredAnnotations

  public Annotation[] getDeclaredAnnotations()

  Returns annotations that aredirectly present on this element. This method ignores inherited annotations. If there are no annotationsdirectly present on this element, the return value is an array of length 0. The caller of this method is free to modify the returned array; it will have no effect on the arrays returned to other callers. This method returns an empty array when invoked on an unnamed module.

  Note that any annotations returned by this method are declaration annotations.

  Specified by:

  getDeclaredAnnotations in interface AnnotatedElement

  Returns:

  annotations directly present on this element

• getResourceAsStream

  public InputStream getResourceAsStream(String name) throwsIOException

  Returns an input stream for reading a resource in this module. Thename parameter is a'/'-separated path name that identifies the resource. As withClass.getResourceAsStream, this method delegates to the module's class loaderfindResource(String,String) method, invoking it with the module name (ornull when the module is unnamed) and the name of the resource. If the resource name has a leading slash then it is dropped before delegation.

  A resource in a named module may beencapsulated so that it cannot be located by code in other modules. Whether a resource can be located or not is determined as follows:

  • If the resource name ends with ".class" then it is not encapsulated.
  • Apackage name is derived from the resource name. If the package name is apackage in the module then the resource can only be located by the caller of this method when the package isopen to at least the caller's module. If the resource is not in a package in the module then the resource is not encapsulated.

  In the above, thepackage name for a resource is derived from the subsequence of characters that precedes the last'/' in the name and then replacing each'/' character in the subsequence with'.'. A leading slash is ignored when deriving the package name. As an example, the package name derived for a resource named "a/b/c/foo.properties" is "a.b.c". A resource name with the name "META-INF/MANIFEST.MF" is never encapsulated because "META-INF" is not a legal package name.

  This method returnsnull if the resource is not in this module, the resource is encapsulated and cannot be located by the caller, or access to the resource is denied by the security manager.

  Parameters:

  name - The resource name

  Returns:

  An input stream for reading the resource ornull

  Throws:

  IOException - If an I/O error occurs

  See Also:

  • Class.getResourceAsStream(String)

• toString

  public String toString()

  Returns the string representation of this module. For a named module, the representation is the string"module", followed by a space, and then the module name. For an unnamed module, the representation is the string"unnamed module", followed by a space, and then an implementation specific string that identifies the unnamed module.

  Overrides:

  toString in class Object

  Returns:

  The string representation of this module