src/java.base/share/classes/java/lang/classfile/attribute/MethodParametersAttribute.java

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package java.lang.classfile.attribute;

import java.lang.classfile.Attribute;
import java.lang.classfile.AttributeMapper;
import java.lang.classfile.Attributes;
import java.lang.classfile.ClassFile;
import java.lang.classfile.MethodElement;
import java.lang.reflect.Executable;
import java.util.List;

import jdk.internal.classfile.impl.BoundAttribute;
import jdk.internal.classfile.impl.UnboundAttribute;

/**
 * Models the {@link Attributes#methodParameters() MethodParameters} attribute
 * (JVMS {@jvms 4.7.24}), which records reflective information about this
 * method's parameters such as access modifiers.
 * <p>
 * This attribute only appears on methods, and does not permit {@linkplain
 * AttributeMapper#allowMultiple multiple instances} in a method.  It has a
 * data dependency on the {@linkplain AttributeMapper.AttributeStability#CP_REFS
 * constant pool}.
 * <p>
 * The attribute was introduced in the Java SE Platform version 8, major version
 * {@value ClassFile#JAVA_8_VERSION}.
 *
 * @see Attributes#methodParameters()
 * @see Executable#getParameters()
 * @jvms 4.7.24 The {@code MethodParameters} Attribute
 * @since 24
 */
public sealed interface MethodParametersAttribute
        extends Attribute<MethodParametersAttribute>, MethodElement
        permits BoundAttribute.BoundMethodParametersAttribute,
                UnboundAttribute.UnboundMethodParametersAttribute {

    /**
     * {@return information about the parameters of the method}  The i'th entry
     * in the list corresponds to the i'th parameter in the method descriptor.
     */
    List<MethodParameterInfo> parameters();

    /**
     * {@return a {@code MethodParameters} attribute}
     * @param parameters the method parameter descriptions
     */
    static MethodParametersAttribute of(List<MethodParameterInfo> parameters) {
        return new UnboundAttribute.UnboundMethodParametersAttribute(parameters);
    }

    /**
     * {@return a {@code MethodParameters} attribute}
     * @param parameters the method parameter descriptions
     */
    static MethodParametersAttribute of(MethodParameterInfo... parameters) {
        return of(List.of(parameters));
    }
}