JDK 17 jdk.incubator.foreign.jmod - JDK Incubator Foreign
JDK 17 jdk.incubator.foreign.jmod is the JMOD file for JDK 17 HTTP Server module.
JDK 17 Incubator Foreign module compiled class files are stored in \fyicenter\jdk-17.0.5\jmods\jdk.incubator.foreign.jmod.
JDK 17 Incubator Foreign module compiled class files are also linked and stored in the \fyicenter\jdk-17.0.5\lib\modules JImage file.
JDK 17 Incubator Foreign module source code files are stored in \fyicenter\jdk-17.0.5\lib\src.zip\jdk.incubator.foreign.
You can click and view the content of each source code file in the list below.
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⏎ jdk/internal/foreign/ResourceScopeImpl.java
/*
* Copyright (c) 2019, 2020, Oracle and/or its affiliates. All rights reserved.
* ORACLE PROPRIETARY/CONFIDENTIAL. Use is subject to license terms.
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package jdk.internal.foreign;
import jdk.incubator.foreign.MemorySegment;
import jdk.incubator.foreign.ResourceScope;
import jdk.incubator.foreign.SegmentAllocator;
import jdk.internal.misc.ScopedMemoryAccess;
import jdk.internal.ref.CleanerFactory;
import java.lang.ref.Cleaner;
import java.lang.ref.Reference;
import java.util.Objects;
/**
* This class manages the temporal bounds associated with a memory segment as well
* as thread confinement. A scope has a liveness bit, which is updated when the scope is closed
* (this operation is triggered by {@link ResourceScope#close()}). This bit is consulted prior
* to memory access (see {@link #checkValidState()}).
* There are two kinds of memory scope: confined memory scope and shared memory scope.
* A confined memory scope has an associated owner thread that confines some operations to
* associated owner thread such as {@link #close()} or {@link #checkValidState()}.
* Shared scopes do not feature an owner thread - meaning their operations can be called, in a racy
* manner, by multiple threads. To guarantee temporal safety in the presence of concurrent thread,
* shared scopes use a more sophisticated synchronization mechanism, which guarantees that no concurrent
* access is possible when a scope is being closed (see {@link jdk.internal.misc.ScopedMemoryAccess}).
*/
public abstract non-sealed class ResourceScopeImpl implements ResourceScope, ScopedMemoryAccess.Scope, SegmentAllocator {
final ResourceList resourceList;
@Override
public void addCloseAction(Runnable runnable) {
Objects.requireNonNull(runnable);
addInternal(ResourceList.ResourceCleanup.ofRunnable(runnable));
}
@Override
public boolean isImplicit() {
return false;
}
/**
* Add a cleanup action. If a failure occurred (because of a add vs. close race), call the cleanup action.
* This semantics is useful when allocating new memory segments, since we first do a malloc/mmap and _then_
* we register the cleanup (free/munmap) against the scope; so, if registration fails, we still have to
* cleanup memory. From the perspective of the client, such a failure would manifest as a factory
* returning a segment that is already "closed" - which is always possible anyway (e.g. if the scope
* is closed _after_ the cleanup for the segment is registered but _before_ the factory returns the
* new segment to the client). For this reason, it's not worth adding extra complexity to the segment
* initialization logic here - and using an optimistic logic works well in practice.
*/
public void addOrCleanupIfFail(ResourceList.ResourceCleanup resource) {
try {
addInternal(resource);
} catch (Throwable ex) {
resource.cleanup();
}
}
void addInternal(ResourceList.ResourceCleanup resource) {
try {
checkValidStateSlow();
resourceList.add(resource);
} catch (ScopedMemoryAccess.Scope.ScopedAccessError err) {
throw new IllegalStateException("Already closed");
}
}
protected ResourceScopeImpl(Cleaner cleaner, ResourceList resourceList) {
this.resourceList = resourceList;
if (cleaner != null) {
cleaner.register(this, resourceList);
}
}
public static ResourceScopeImpl createImplicitScope() {
return new ImplicitScopeImpl(CleanerFactory.cleaner());
}
public static ResourceScopeImpl createConfined(Thread thread, Cleaner cleaner) {
return new ConfinedScope(thread, cleaner);
}
/**
* Creates a confined memory scope with given attachment and cleanup action. The returned scope
* is assumed to be confined on the current thread.
* @return a confined memory scope
*/
public static ResourceScopeImpl createConfined(Cleaner cleaner) {
return new ConfinedScope(Thread.currentThread(), cleaner);
}
/**
* Creates a shared memory scope with given attachment and cleanup action.
* @return a shared memory scope
*/
public static ResourceScopeImpl createShared(Cleaner cleaner) {
return new SharedScope(cleaner);
}
private final void release0(HandleImpl handle) {
try {
Objects.requireNonNull(handle);
if (handle.scope() != this) {
throw new IllegalArgumentException("Cannot release an handle acquired from another scope");
}
handle.release();
} finally {
Reference.reachabilityFence(this);
}
}
@Override
public final void release(ResourceScope.Handle handle) {
release0((HandleImpl)handle);
}
@Override
public final void release(ScopedMemoryAccess.Scope.Handle handle) {
release0((HandleImpl)handle);
}
@Override
public abstract HandleImpl acquire();
/**
* Internal interface used to implement resource scope handles.
*/
public non-sealed interface HandleImpl extends ResourceScope.Handle, ScopedMemoryAccess.Scope.Handle {
@Override
ResourceScopeImpl scope();
void release();
}
/**
* Closes this scope, executing any cleanup action (where provided).
* @throws IllegalStateException if this scope is already closed or if this is
* a confined scope and this method is called outside of the owner thread.
*/
public void close() {
try {
justClose();
resourceList.cleanup();
} finally {
Reference.reachabilityFence(this);
}
}
abstract void justClose();
/**
* Returns "owner" thread of this scope.
* @return owner thread (or null for a shared scope)
*/
public abstract Thread ownerThread();
/**
* Returns true, if this scope is still alive. This method may be called in any thread.
* @return {@code true} if this scope is not closed yet.
*/
public abstract boolean isAlive();
/**
* This is a faster version of {@link #checkValidStateSlow()}, which is called upon memory access, and which
* relies on invariants associated with the memory scope implementations (typically, volatile access
* to the closed state bit is replaced with plain access, and ownership check is removed where not needed.
* Should be used with care.
*/
public abstract void checkValidState();
/**
* Checks that this scope is still alive (see {@link #isAlive()}).
* @throws IllegalStateException if this scope is already closed or if this is
* a confined scope and this method is called outside of the owner thread.
*/
public final void checkValidStateSlow() {
if (ownerThread() != null && Thread.currentThread() != ownerThread()) {
throw new IllegalStateException("Attempted access outside owning thread");
} else if (!isAlive()) {
throw new IllegalStateException("Already closed");
}
}
@Override
protected Object clone() throws CloneNotSupportedException {
throw new CloneNotSupportedException();
}
/**
* Allocates a segment using this scope. Used by {@link SegmentAllocator#ofScope(ResourceScope)}.
*/
@Override
public MemorySegment allocate(long bytesSize, long bytesAlignment) {
return MemorySegment.allocateNative(bytesSize, bytesAlignment, this);
}
/**
* A non-closeable, shared scope. Similar to a shared scope, but its {@link #close()} method throws unconditionally.
* In addition, non-closeable scopes feature a much simpler scheme for generating resource scope handles, where
* the scope itself also acts as a resource scope handle and is returned by {@link #acquire()}.
*/
static class ImplicitScopeImpl extends SharedScope implements HandleImpl {
public ImplicitScopeImpl(Cleaner cleaner) {
super(cleaner);
}
@Override
public HandleImpl acquire() {
return this;
}
@Override
public boolean isImplicit() {
return true;
}
@Override
public void close() {
throw new UnsupportedOperationException("Scope cannot be closed");
}
@Override
public void release() {
// do nothing
}
@Override
public ResourceScopeImpl scope() {
return this;
}
}
/**
* The global, always alive, non-closeable, shared scope. This is like a {@link ImplicitScopeImpl non-closeable scope},
* except that the operation which adds new resources to the global scope does nothing: as the scope can never
* become not-alive, there is nothing to track.
*/
public static final ResourceScopeImpl GLOBAL = new ImplicitScopeImpl( null) {
@Override
void addInternal(ResourceList.ResourceCleanup resource) {
// do nothing
}
};
/**
* A list of all cleanup actions associated with a resource scope. Cleanup actions are modelled as instances
* of the {@link ResourceCleanup} class, and, together, form a linked list. Depending on whether a scope
* is shared or confined, different implementations of this class will be used, see {@link ConfinedScope.ConfinedResourceList}
* and {@link SharedScope.SharedResourceList}.
*/
public abstract static class ResourceList implements Runnable {
ResourceCleanup fst;
abstract void add(ResourceCleanup cleanup);
abstract void cleanup();
public final void run() {
cleanup(); // cleaner interop
}
static void cleanup(ResourceCleanup first) {
ResourceCleanup current = first;
while (current != null) {
current.cleanup();
current = current.next;
}
}
public static abstract class ResourceCleanup {
ResourceCleanup next;
public abstract void cleanup();
static final ResourceCleanup CLOSED_LIST = new ResourceCleanup() {
@Override
public void cleanup() {
throw new IllegalStateException("This resource list has already been closed!");
}
};
static ResourceCleanup ofRunnable(Runnable cleanupAction) {
return new ResourceCleanup() {
@Override
public void cleanup() {
cleanupAction.run();
}
};
}
}
}
}
⏎ jdk/internal/foreign/ResourceScopeImpl.java
Or download all of them as a single archive file:
File name: jdk.incubator.foreign-17.0.5-src.zip File size: 168767 bytes Release date: 2022-09-13 Download
⇒ JDK 17 jdk.incubator.vector.jmod - JDK Incubator Vector
2023-10-04, 3899👍, 0💬
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