public void visitImplementation(Class<?> implementation) {
            visitImplementation(ImplementationSnapshot.of(implementation, classLoaderHierarchyHasher));
        }

        @Override
        public void visitImplementation(ImplementationSnapshot implementation) {
            if (this.implementation == null) {
                this.implementation = implementation;
            } else {

/**
 * Represents a filter for a implementation of a Java Virtual Machine.
 *
 * @since 6.8
 */
public final class JvmImplementation {

    /**
     * Vendor-specific virtual machine implementation.
     *
     * Acts as a placeholder and matches any implementation from any vendor.
     * Usually used to override specific implementation requests.
     */

     * @param serviceInstance The service implementation.
     */
    <T> void add(Class<T> serviceType, T serviceInstance);

    /**
     * Adds a service to this registry. The implementation class should have a single public constructor, and this constructor can take services to be injected as parameters.
     *
     * @param serviceType The service implementation to make visible.
     */
    void add(Class<?> serviceType);

 * </ul>
 *
 * <p>
 * A value source implementation will most likely take parameters. To do this create a
 * subtype of {@link ValueSourceParameters} and declare this type as the type parameter
 * to the value source implementation.
 * </p>
 *
 * <p>
 * A value source implementation doesn't have to be thread-safe, as the single call
 * to {@link #obtain()} is synchronized.
 * </p>

    /**
     * Writes a signed 64 bit long value. The implementation may encode the value as a variable number of bytes, not necessarily as 8 bytes.
     */
    void writeLong(long value) throws IOException;

    /**
     * Writes a signed 64 bit long value whose value is likely to be small and positive but may not be. The implementation may encode the value in a way that is more efficient for small positive
     * values.

     *
     * @since 6.8
     */
    Property<JvmVendorSpec> getVendor();

    /**
     * The virtual machine implementation of the toolchain.
     * <p>
     * By default, any implementation (hotspot, j9, ...) is eligible.
     * <p>
     * Note that the implementation can only be configured if the {@link #getLanguageVersion() language version} is configured as well.
     *
     * @since 6.8
     */

import java.io.Serializable;
import java.util.Collections;
import java.util.concurrent.Callable;
import java.util.concurrent.CountDownLatch;

/**
 * Worker-side implementation of {@link RequestProtocol} executing actions.
 */
public class WorkerAction implements Action<WorkerProcessContext>, Serializable, RequestProtocol, StreamFailureHandler, Stoppable, StreamCompletion {

    private final String vendor;
    private final String implementation;

    public JavaToolchainInput(JavaToolchainSpec spec) {
        this.javaLanguageVersion = spec.getLanguageVersion().getOrNull();
        this.vendor = spec.getVendor().get().toString();
        this.implementation = spec.getImplementation().get().toString();
    }

    @Optional
    @Input

 * should override {@code equals} as well, either providing your own implementation, or delegating
 * to the provided {@code standardEquals} method.
 *
 * <p>Each of the {@code standard} methods, where appropriate, use {@link Objects#equal} to test
 * equality for both keys and values. This may not be the desired behavior for map implementations
 * that use non-standard notions of key equality, such as the entry of a {@code SortedMap} whose

import java.util.Queue;
import java.util.concurrent.atomic.AtomicReference;

public class IsolationScheme<IMPLEMENTATION, PARAMS> {
    private final Class<IMPLEMENTATION> interfaceType;
    private final Class<PARAMS> paramsType;
    private final Class<? extends PARAMS> noParamsType;

    public IsolationScheme(Class<IMPLEMENTATION> interfaceType, Class<PARAMS> paramsType, Class<? extends PARAMS> noParamsType) {