Class ModuleLayer.Controller

java.lang.Object

java.lang.ModuleLayer.Controller

Enclosing class:: ModuleLayer

public static final class ModuleLayer.Controller extends Object

Controls a module layer. The static methods defined by ModuleLayer to create module layers return a Controller that can be used to control modules in the layer.

Unless otherwise specified, passing a null argument to a method in this class causes a NullPointerException to be thrown.

API Note:: Care should be taken with Controller objects, they should never be shared with untrusted code.
Since:: 9

Method Summary

Modifier and Type	Method	Description
`ModuleLayer.Controller`	`addExports(Module source, String pn, Module target)`	Updates module `source` in the layer to export a package to module `target`.
`ModuleLayer.Controller`	`addOpens(Module source, String pn, Module target)`	Updates module `source` in the layer to open a package to module `target`.
`ModuleLayer.Controller`	`addReads(Module source, Module target)`	Updates module `source` in the layer to read module `target`.
`ModuleLayer.Controller`	`enableNativeAccess(Module target)`	Restricted. Enables native access for a module in the layer if the caller's module has native access.
`ModuleLayer`	`layer()`	Returns the layer that this object controls.

Methods declared in class Object

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

Modifier and Type	Method	Description
`protected Object`	`clone()`	Creates and returns a copy of this object.
`boolean`	`equals(Object obj)`	Indicates whether some other object is "equal to" this one.
`protected void`	`finalize()`	Deprecated, for removal: This API element is subject to removal in a future version. Finalization is deprecated and subject to removal in a future release.
`final Class<?>`	`getClass()`	Returns the runtime class of this `Object`.
`int`	`hashCode()`	Returns a hash code value for this object.
`final void`	`notify()`	Wakes up a single thread that is waiting on this object's monitor.
`final void`	`notifyAll()`	Wakes up all threads that are waiting on this object's monitor.
`String`	`toString()`	Returns a string representation of the object.
`final void`	`wait()`	Causes the current thread to wait until it is awakened, typically by being notified or interrupted.
`final void`	`wait(long timeoutMillis)`	Causes the current thread to wait until it is awakened, typically by being notified or interrupted, or until a certain amount of real time has elapsed.
`final void`	`wait(long timeoutMillis, int nanos)`	Causes the current thread to wait until it is awakened, typically by being notified or interrupted, or until a certain amount of real time has elapsed.

Method Details

layer

public ModuleLayer layer()

Returns the layer that this object controls.

Returns:: the module layer

addReads

public ModuleLayer.Controller addReads(Module source, Module target)

Updates module source in the layer to read module target. This method is a no-op if source already reads target.

Implementation Note:

Read edges added by this method are weak and do not prevent target from being GC'ed when source is strongly reachable.

Parameters:

source - The source module

target - The target module to read

Returns:

This controller

Throws:

IllegalArgumentException - If source is not in the module layer

See Also:

addExports

public ModuleLayer.Controller addExports(Module source, String pn, Module target)

Updates module source in the layer to export a package to module target. This method is a no-op if source already exports the package to at least target.

Exporting a package with this method does not allow the target module to reflectively set or obtain a method handle with write access to a public final field declared in a public class in the package.

Parameters:

source - The source module

pn - The package name

target - The target module

Returns:

This controller

Throws:

IllegalArgumentException - If source is not in the module layer or the package is not in the source module

See Also:

addOpens

public ModuleLayer.Controller addOpens(Module source, String pn, Module target)

Updates module source in the layer to open a package to module target. This method is a no-op if source already opens the package to at least target.

Opening a package with this method does not allow the target module to reflectively set or obtain a method handle with write access to a final field declared in a class in the package.

Parameters:

source - The source module

pn - The package name

target - The target module

Returns:

This controller

Throws:

IllegalArgumentException - If source is not in the module layer or the package is not in the source module

See Also:

enableNativeAccess

public ModuleLayer.Controller enableNativeAccess(Module target)

enableNativeAccess is a restricted method of the Java platform.

Programs can only use enableNativeAccess when access to restricted methods is enabled.

Restricted methods are unsafe, and, if used incorrectly, might crash the JVM or result in memory corruption.

Enables native access for a module in the layer if the caller's module has native access.

Parameters:: target - The module to update
Returns:: This controller
Throws:: IllegalArgumentException - If target is not in the module layer; IllegalCallerException - If the caller is in a module that does not have native access enabled
Since:: 22

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