src/java.base/share/classes/java/lang/classfile/CodeModel.java

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package java.lang.classfile;

import java.lang.classfile.ClassFile.DeadLabelsOption;
import java.lang.classfile.ClassFile.DebugElementsOption;
import java.lang.classfile.ClassFile.LineNumbersOption;
import java.lang.classfile.attribute.BootstrapMethodsAttribute;
import java.lang.classfile.attribute.CodeAttribute;
import java.lang.classfile.attribute.StackMapTableAttribute;
import java.lang.classfile.instruction.ExceptionCatch;
import java.util.List;
import java.util.Optional;
import java.util.function.Consumer;

import jdk.internal.classfile.impl.BufferedCodeBuilder;

/**
 * Models the body of a method (the {@code Code} attribute).  A {@code Code}
 * attribute is viewed as a {@linkplain CompoundElement composition} of {@link
 * CodeElement}s, which is the only way to access {@link Instruction}s; the
 * order of elements of a code model is significant.
 * <p>
 * A {@code CodeModel} is obtained from {@link MethodModel#code()}, or in the
 * traversal of the member elements of a method.
 * <p>
 * {@link MethodBuilder#withCode} is the main way to build code models.  {@link
 * MethodBuilder#transformCode} and {@link CodeBuilder#transforming} allow
 * creating new {@code Code} attributes by selectively processing the original
 * code elements and directing the results to a code builder.
 * <p>
 * A {@code Code} attribute holds attributes, but they are usually not member
 * elements, but are decomposed to {@link PseudoInstruction}, accessible
 * according to {@link DeadLabelsOption}, {@link DebugElementsOption}, and
 * {@link LineNumbersOption}.  {@link StackMapTableAttribute} can only be
 * accessed via {@linkplain AttributedElement explicit attribute reading}, as it
 * is considered a derived property from the code body.
 *
 * @see MethodModel#code()
 * @see CodeTransform
 * @see CodeAttribute
 * @jvms 4.7.3 The {@code Code} Attribute
 * @since 24
 */
public sealed interface CodeModel
        extends CompoundElement<CodeElement>, AttributedElement, MethodElement
        permits CodeAttribute, BufferedCodeBuilder.Model {

    /**
     * {@return the enclosing method, if known}
     */
    Optional<MethodModel> parent();

    /**
     * {@return the exception table of the method}  The exception table is also
     * modeled by {@link ExceptionCatch} elements in the streaming view.
     */
    List<ExceptionCatch> exceptionHandlers();
}