jdk/src/java.base/share/classes/java/lang/classfile/attribute/ModuleProvideInfo.java

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package java.lang.classfile.attribute;

import java.lang.classfile.constantpool.ClassEntry;
import java.lang.constant.ClassDesc;
import java.lang.module.ModuleDescriptor;
import java.util.Arrays;
import java.util.List;

import jdk.internal.classfile.impl.TemporaryConstantPool;
import jdk.internal.classfile.impl.UnboundAttribute;
import jdk.internal.classfile.impl.Util;

/**
 * Models a single "provides" declaration in the {@link ModuleAttribute}.
 *
 * @see ModuleAttribute#provides()
 * @see ModuleDescriptor.Provides
 * @jvms 4.7.25 The {@code Module} Attribute
 * @since 24
 */
public sealed interface ModuleProvideInfo
        permits UnboundAttribute.UnboundModuleProvideInfo {

    /**
     * {@return the service interface representing the provided service}
     *
     * @see ModuleDescriptor.Provides#service()
     */
    ClassEntry provides();

    /**
     * {@return the classes providing the service implementation}  The list
     * should not be empty.
     *
     * @see ModuleDescriptor.Provides#providers()
     */
    List<ClassEntry> providesWith();

    /**
     * {@return a service provision description}
     * @param provides the service class interface
     * @param providesWith the service class implementations, must not be empty
     */
    static ModuleProvideInfo of(ClassEntry provides,
                                List<ClassEntry> providesWith) {
        return new UnboundAttribute.UnboundModuleProvideInfo(provides, providesWith);
    }

    /**
     * {@return a service provision description}
     * @param provides the service class interface
     * @param providesWith the service class implementations, must not be empty
     */
    static ModuleProvideInfo of(ClassEntry provides,
                                ClassEntry... providesWith) {
        return of(provides, List.of(providesWith));
    }

    /**
     * {@return a service provision description}
     * @param provides the service class interface
     * @param providesWith the service class implementations, must not be empty
     * @throws IllegalArgumentException if {@code provides} or any of {@code
     *         providesWith} represents a primitive type
     */
    static ModuleProvideInfo of(ClassDesc provides,
                                List<ClassDesc> providesWith) {
        return of(TemporaryConstantPool.INSTANCE.classEntry(provides), Util.entryList(providesWith));
    }

    /**
     * {@return a service provision description}
     * @param provides the service class interface
     * @param providesWith the service class implementations, must not be empty
     * @throws IllegalArgumentException if {@code provides} or any of {@code
     *         providesWith} represents a primitive type
     */
    static ModuleProvideInfo of(ClassDesc provides,
                                ClassDesc... providesWith) {
        // List view, since ref to providesWith is temporary
        return of(provides, Arrays.asList(providesWith));
    }
}