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

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package java.lang.classfile.attribute;

import java.lang.classfile.Attribute;
import java.lang.classfile.AttributeMapper;
import java.lang.classfile.AttributeMapper.AttributeStability;
import java.lang.classfile.Attributes;
import java.lang.classfile.BootstrapMethodEntry;
import java.lang.classfile.ClassFile;
import java.lang.classfile.ClassModel;
import java.lang.classfile.constantpool.ConstantPool;
import java.lang.classfile.constantpool.ConstantPoolBuilder;
import java.util.List;

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

/**
 * Models the {@link Attributes#bootstrapMethods() BootstrapMethods} attribute
 * (JVMS {@jvms 4.7.23}), which stores symbolic information for the execution of
 * bootstrap methods, used by dynamically-computed call sites and constants.
 * It is logically a part of the constant pool of a {@code class} file and thus
 * not delivered in {@link ClassModel} traversal; its elements are accessible
 * through {@link ConstantPool}.
 * <p>
 * This attribute only appears on classes, and does not permit {@linkplain
 * AttributeMapper#allowMultiple multiple instances} in a class.  It has a
 * data dependency on the {@linkplain AttributeStability#CP_REFS constant pool}.
 * <p>
 * This attribute cannot be constructed directly; its entries can be constructed
 * through {@link ConstantPoolBuilder#bsmEntry}, resulting in at most one
 * attribute instance in the built {@code class} file.
 * <p>
 * The attribute was introduced in the Java SE Platform version 7, major version
 * {@value ClassFile#JAVA_7_VERSION}.
 *
 * @see Attributes#bootstrapMethods()
 * @see java.lang.invoke##bsm Execution of bootstrap methods
 * @jvms 4.7.23 The {@code BootstrapMethods} Attribute
 * @since 24
 */
public sealed interface BootstrapMethodsAttribute
        extends Attribute<BootstrapMethodsAttribute>
        permits BoundAttribute.BoundBootstrapMethodsAttribute,
                UnboundAttribute.EmptyBootstrapAttribute {

    /**
     * {@return the elements of the bootstrap method table}
     */
    List<BootstrapMethodEntry> bootstrapMethods();

    /**
     * {@return the size of the bootstrap methods table}
     */
    int bootstrapMethodsSize();

    // No factories; BMA is generated as part of constant pool
}