src/java.base/share/classes/java/lang/classfile/attribute/StackMapTableAttribute.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.ClassFile;
import java.lang.classfile.CodeElement;
import java.lang.classfile.instruction.DiscontinuedInstruction;
import java.util.List;

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

/**
 * Models the {@link Attributes#stackMapTable() StackMapTable} attribute (JVMS
 * {@jvms 4.7.4}), which is used for verification by type checking ({@jvms
 * 4.10.1}).
 * <p>
 * This attribute is not delivered in the traversal of a {@link CodeAttribute},
 * but instead automatically generated upon {@code class} file writing.
 * Advanced users can supply their own stack maps according to the {@link
 * ClassFile.StackMapsOption}.
 * <p>
 * This attribute only appears on {@code Code} attributes, and does not permit
 * {@linkplain AttributeMapper#allowMultiple multiple instances} in a {@code
 * Code} attribute.  It has a data dependency on {@linkplain
 * AttributeStability#LABELS labels} in the {@code code} array.
 * <p>
 * This attribute was introduced in the Java SE Platform version 6, major
 * version {@value ClassFile#JAVA_6_VERSION}.
 *
 * @see Attributes#stackMapTable()
 * @see DiscontinuedInstruction.JsrInstruction
 * @see DiscontinuedInstruction.RetInstruction
 * @jvms 4.7.4 The {@code StackMapTable} Attribute
 * @jvms 4.10.1 Verification by Type Checking
 * @since 24
 */
public sealed interface StackMapTableAttribute
        extends Attribute<StackMapTableAttribute>, CodeElement
        permits BoundAttribute.BoundStackMapTableAttribute, UnboundAttribute.UnboundStackMapTableAttribute {

    /**
     * {@return the stack map frames}
     */
    List<StackMapFrameInfo> entries();

    /**
     * {@return a stack map table attribute}
     *
     * @param entries the stack map frames
     */
    public static StackMapTableAttribute of(List<StackMapFrameInfo> entries) {
        return new UnboundAttribute.UnboundStackMapTableAttribute(entries);
    }
}