src/java.base/share/classes/java/lang/classfile/instruction/LookupSwitchInstruction.java

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package java.lang.classfile.instruction;

import java.lang.classfile.CodeBuilder;
import java.lang.classfile.CodeElement;
import java.lang.classfile.CodeModel;
import java.lang.classfile.Instruction;
import java.lang.classfile.Label;
import java.lang.classfile.Opcode;
import java.util.List;

import jdk.internal.classfile.impl.AbstractInstruction;

/**
 * Models a {@link Opcode#LOOKUPSWITCH lookupswitch} instruction in the {@code
 * code} array of a {@code Code} attribute.  Delivered as a {@link CodeElement}
 * when traversing the elements of a {@link CodeModel}.
 * <p>
 * A lookup switch instruction is composite:
 * {@snippet lang=text :
 * // @link substring="LookupSwitchInstruction" target="#of" :
 * LookupSwitchInstruction(
 *     Label defaultTarget, // @link substring="defaultTarget" target="#defaultTarget"
 *     List<SwitchCase> cases // @link substring="cases" target="#cases()"
 * )
 * }
 * If elements in {@code cases} are not sorted ascending by their {@link
 * SwitchCase#caseValue caseValue}, a sorted version of the {@code cases} list
 * will be written instead.
 *
 * @see Opcode.Kind#LOOKUP_SWITCH
 * @see CodeBuilder#lookupswitch CodeBuilder::lookupswitch
 * @jvms 6.5.lookupswitch <em>lookupswitch</em>
 * @since 24
 */
public sealed interface LookupSwitchInstruction extends Instruction
        permits AbstractInstruction.BoundLookupSwitchInstruction,
                AbstractInstruction.UnboundLookupSwitchInstruction {
    /**
     * {@return the target of the default case}
     */
    Label defaultTarget();

    /**
     * {@return the cases of the switch}
     */
    List<SwitchCase> cases();

    /**
     * {@return a lookup switch instruction}
     *
     * @param defaultTarget the default target of the switch
     * @param cases the cases of the switch
     */
    static LookupSwitchInstruction of(Label defaultTarget, List<SwitchCase> cases) {
        return new AbstractInstruction.UnboundLookupSwitchInstruction(defaultTarget, cases);
    }
}