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package org.graalvm.nativeimage;

import java.util.Objects;

import org.graalvm.nativeimage.impl.IsolateSupport;
import org.graalvm.word.UnsignedWord;


Support for the creation, access to, and tear-down of isolates.

Since:19.0
/**
 * Support for the creation, access to, and tear-down of isolates.
 *
 * @since 19.0
 */
public final class Isolates {
    private Isolates() {
    }

    
An exception thrown in the context of managing isolates.

Since:19.0
/**
     * An exception thrown in the context of managing isolates.
     *
     * @since 19.0
     */
    public static final class IsolateException extends RuntimeException {
        private static final long serialVersionUID = 1L;

        
Constructs a new exception with the specified detail message.

Since:19.0
/**
         * Constructs a new exception with the specified detail message.
         *
         * @since 19.0
         */
        public IsolateException(String message) {
            super(message);
        }
    }

    
Parameters for the creation of an isolate.

See Also:
  • Builder
Since:19.0
/**
     * Parameters for the creation of an isolate.
     *
     * @see CreateIsolateParameters.Builder
     *
     * @since 19.0
     */
    public static final class CreateIsolateParameters {

        
Builder for a CreateIsolateParameters instance. 
Since:19.0
/**
         * Builder for a {@link CreateIsolateParameters} instance.
         *
         * @since 19.0
         */
        public static final class Builder {
            private UnsignedWord reservedAddressSpaceSize;
            private String auxiliaryImagePath;
            private UnsignedWord auxiliaryImageReservedSpaceSize;

            
Creates a new builder with default values.

Since:19.0
/**
             * Creates a new builder with default values.
             *
             * @since 19.0
             */
            public Builder() {
            }

            
Sets the size in bytes for the reserved virtual address space of the new isolate.

Since:19.0
/**
             * Sets the size in bytes for the reserved virtual address space of the new isolate.
             *
             * @since 19.0
             */
            public Builder reservedAddressSpaceSize(UnsignedWord size) {
                this.reservedAddressSpaceSize = size;
                return this;
            }

            
Sets the file path to an auxiliary image which should be loaded in addition to the main image, or null if no such image should be loaded. 
Since:20.1
/**
             * Sets the file path to an auxiliary image which should be loaded in addition to the
             * main image, or {@code null} if no such image should be loaded.
             *
             * @since 20.1
             */
            public Builder auxiliaryImagePath(String filePath) {
                this.auxiliaryImagePath = filePath;
                return this;
            }

            
Sets the size in bytes of an address space to reserve for loading an auxiliary image
in addition to the main image, or 0 if no space should be reserved.

Since:20.1
/**
             * Sets the size in bytes of an address space to reserve for loading an auxiliary image
             * in addition to the main image, or 0 if no space should be reserved.
             *
             * @since 20.1
             */
            public Builder auxiliaryImageReservedSpaceSize(UnsignedWord size) {
                this.auxiliaryImageReservedSpaceSize = size;
                return this;
            }

            
Produces the final CreateIsolateParameters with the values set previously by the builder methods. 
Since:19.0
/**
             * Produces the final {@link CreateIsolateParameters} with the values set previously by
             * the builder methods.
             *
             * @since 19.0
             */
            public CreateIsolateParameters build() {
                return new CreateIsolateParameters(reservedAddressSpaceSize, auxiliaryImagePath, auxiliaryImageReservedSpaceSize);
            }
        }

        private static final CreateIsolateParameters DEFAULT = new Builder().build();

        
Returns a CreateIsolateParameters with all default values. 
Since:19.0
/**
         * Returns a {@link CreateIsolateParameters} with all default values.
         *
         * @since 19.0
         */
        public static CreateIsolateParameters getDefault() {
            return DEFAULT;
        }

        private final UnsignedWord reservedAddressSpaceSize;
        private final String auxiliaryImagePath;
        private final UnsignedWord auxiliaryImageReservedSpaceSize;

        private CreateIsolateParameters(UnsignedWord reservedAddressSpaceSize, String auxiliaryImagePath, UnsignedWord auxiliaryImageReservedSpaceSize) {
            this.reservedAddressSpaceSize = reservedAddressSpaceSize;
            this.auxiliaryImagePath = auxiliaryImagePath;
            this.auxiliaryImageReservedSpaceSize = auxiliaryImageReservedSpaceSize;
        }

        
Returns the size in bytes for the reserved virtual address space of the new isolate.

Since:19.0
/**
         * Returns the size in bytes for the reserved virtual address space of the new isolate.
         *
         * @since 19.0
         */
        public UnsignedWord getReservedAddressSpaceSize() {
            return reservedAddressSpaceSize;
        }

        
Returns the file path to an auxiliary image which should be loaded in addition to the main image, or null if no such image should be loaded. 
Since:20.1
/**
         * Returns the file path to an auxiliary image which should be loaded in addition to the
         * main image, or {@code null} if no such image should be loaded.
         *
         * @since 20.1
         */
        public String getAuxiliaryImagePath() {
            return auxiliaryImagePath;
        }

        
Returns the size in bytes of an address space to reserve for loading an auxiliary image
in addition to the main image, or 0 if no space should be reserved.

Since:20.1
/**
         * Returns the size in bytes of an address space to reserve for loading an auxiliary image
         * in addition to the main image, or 0 if no space should be reserved.
         *
         * @since 20.1
         */
        public UnsignedWord getAuxiliaryImageReservedSpaceSize() {
            return auxiliaryImageReservedSpaceSize;
        }
    }

    
Creates a new isolate with the passed parameters. On success, the current thread is attached to the created isolate, and a pointer to its associated IsolateThread structure is returned. 
Params:
  • parameters – Parameters for the creation of the isolate.
Throws:
Returns:A pointer to the structure that represents the current thread in the new isolate.
Since:19.0
/**
     * Creates a new isolate with the passed {@linkplain CreateIsolateParameters parameters}. On
     * success, the current thread is attached to the created isolate, and a pointer to its
     * associated {@link IsolateThread} structure is returned.
     *
     * @param parameters Parameters for the creation of the isolate.
     * @return A pointer to the structure that represents the current thread in the new isolate.
     * @throws IsolateException on error.
     *
     * @since 19.0
     */
    public static IsolateThread createIsolate(CreateIsolateParameters parameters) throws IsolateException {
        Objects.requireNonNull(parameters);
        return ImageSingletons.lookup(IsolateSupport.class).createIsolate(parameters);
    }

    
Attaches the current thread to the passed isolate. If the thread has already been attached,
the call provides the thread's existing isolate thread structure.

Params:
  • isolate – The isolate to which to attach the current thread.
Throws:
Returns:A pointer to the structure representing the newly attached isolate thread.
Since:19.0
/**
     * Attaches the current thread to the passed isolate. If the thread has already been attached,
     * the call provides the thread's existing isolate thread structure.
     *
     * @param isolate The isolate to which to attach the current thread.
     * @return A pointer to the structure representing the newly attached isolate thread.
     * @throws IsolateException on error.
     *
     * @since 19.0
     */
    public static IsolateThread attachCurrentThread(Isolate isolate) throws IsolateException {
        return ImageSingletons.lookup(IsolateSupport.class).attachCurrentThread(isolate);
    }

    
Given an isolate to which the current thread is attached, returns the address of the thread's associated isolate thread structure. If the current thread is not attached to the passed isolate, returns null. 
Params:
  • isolate – The isolate for which to retrieve the current thread's corresponding structure
Throws:
Returns:A pointer to the current thread's structure in the specified isolate or null if the thread is not attached to that isolate.
Since:19.0
/**
     * Given an isolate to which the current thread is attached, returns the address of the thread's
     * associated isolate thread structure. If the current thread is not attached to the passed
     * isolate, returns {@code null}.
     *
     * @param isolate The isolate for which to retrieve the current thread's corresponding structure
     * @return A pointer to the current thread's structure in the specified isolate or {@code null}
     *         if the thread is not attached to that isolate.
     * @throws IsolateException on error.
     *
     * @since 19.0
     */
    public static IsolateThread getCurrentThread(Isolate isolate) throws IsolateException {
        return ImageSingletons.lookup(IsolateSupport.class).getCurrentThread(isolate);
    }

    
Given an isolate thread structure, determines to which isolate it belongs and returns the address of the isolate structure. May return null if the specified isolate thread structure is no longer valid. 
Params:
  • thread – The isolate thread for which to retrieve the isolate.
Throws:
Returns:A pointer to the isolate, or null.
Since:19.0
/**
     * Given an isolate thread structure, determines to which isolate it belongs and returns the
     * address of the isolate structure. May return {@code null} if the specified isolate thread
     * structure is no longer valid.
     *
     * @param thread The isolate thread for which to retrieve the isolate.
     * @return A pointer to the isolate, or {@code null}.
     * @throws IsolateException on error.
     *
     * @since 19.0
     */
    public static Isolate getIsolate(IsolateThread thread) throws IsolateException {
        return ImageSingletons.lookup(IsolateSupport.class).getIsolate(thread);
    }

    
Detaches the passed isolate thread from its isolate and discards any state or context that is
associated with it. At the time of the call, no code may still be executing in the isolate
thread's context. The passed pointer is no longer valid after the method returns.

Params:
  • thread – The isolate thread to detach from its isolate.
Throws:
Since:19.0
/**
     * Detaches the passed isolate thread from its isolate and discards any state or context that is
     * associated with it. At the time of the call, no code may still be executing in the isolate
     * thread's context. The passed pointer is no longer valid after the method returns.
     *
     * @param thread The isolate thread to detach from its isolate.
     * @throws IsolateException on error.
     *
     * @since 19.0
     */
    public static void detachThread(IsolateThread thread) throws IsolateException {
        ImageSingletons.lookup(IsolateSupport.class).detachThread(thread);
    }

    
Tears down an isolate. Given an IsolateThread for the current thread which must be attached to the isolate to be torn down, waits for any other attached threads to detach from the isolate, then discards the isolate's objects, threads, and any other state or context that is associated with it. The passed pointer is no longer valid after the method returns. 
Params:
  • thread – IsolateThread of the current thread that is attached to the isolate which is to be torn down.
Throws:
Since:19.0
/**
     * Tears down an isolate. Given an {@link IsolateThread} for the current thread which must be
     * attached to the isolate to be torn down, waits for any other attached threads to detach from
     * the isolate, then discards the isolate's objects, threads, and any other state or context
     * that is associated with it. The passed pointer is no longer valid after the method returns.
     *
     * @param thread {@link IsolateThread} of the current thread that is attached to the isolate
     *            which is to be torn down.
     * @throws IsolateException on error.
     *
     * @since 19.0
     */
    public static void tearDownIsolate(IsolateThread thread) throws IsolateException {
        ImageSingletons.lookup(IsolateSupport.class).tearDownIsolate(thread);
    }
}