Module java.base

Package java.lang.module

Class ModuleReference

java.lang.Object

java.lang.module.ModuleReference

public abstract class ModuleReference
extends Object

A reference to a module's content.

A module reference is a concrete implementation of this class that implements the abstract methods defined by this class. It contains the module's descriptor and its location, if known. It also has the ability to create a ModuleReader in order to access the module's content, which may be inside the Java run-time system itself or in an artifact such as a modular JAR file.

Since:

9

See Also:

• ModuleFinder
• ModuleReader

Constructor Summary

Constructors

Modifier	Constructor	Description
protected	ModuleReference(ModuleDescriptor descriptor, URI location)	Constructs a new instance of this class.

Method Summary

Modifier and Type	Method	Description
final ModuleDescriptor	descriptor()	Returns the module descriptor.
final Optional<URI>	location()	Returns the location of this module's content, if known.
abstract ModuleReader	open()	Opens the module content for reading.

Methods declared in class java.lang.Object

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

Constructor Details

ModuleReference

protected ModuleReference(ModuleDescriptor descriptor,
 URI location)

Constructs a new instance of this class.

Parameters:

descriptor - The module descriptor

location - The module location or null if not known

Method Details

descriptor

public final ModuleDescriptor descriptor()

Returns the module descriptor.

Returns:

The module descriptor

location

public final Optional<URI> location()

Returns the location of this module's content, if known.

This URI, when present, can be used as the location value of a CodeSource so that a module's classes can be granted specific permissions when loaded by a SecureClassLoader.

Returns:

The location or an empty Optional if not known

open

public abstract ModuleReader open()
                           throws IOException

Opens the module content for reading.

Returns:

A ModuleReader to read the module

Throws:

IOException - If an I/O error occurs

SecurityException - If denied by the security manager