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// ASM: a very small and fast Java bytecode manipulation framework
// Copyright (c) 2000-2011 INRIA, France Telecom
// All rights reserved.
//
// Redistribution and use in source and binary forms, with or without
// modification, are permitted provided that the following conditions
// are met:
// 1. Redistributions of source code must retain the above copyright
//    notice, this list of conditions and the following disclaimer.
// 2. Redistributions in binary form must reproduce the above copyright
//    notice, this list of conditions and the following disclaimer in the
//    documentation and/or other materials provided with the distribution.
// 3. Neither the name of the copyright holders nor the names of its
//    contributors may be used to endorse or promote products derived from
//    this software without specific prior written permission.
//
// THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS IS"
// AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
// IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
// ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT OWNER OR CONTRIBUTORS BE
// LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR
// CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF
// SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS
// INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN
// CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE)
// ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF
// THE POSSIBILITY OF SUCH DAMAGE.
package org.mvel2.asm;

/**
 * A {@link FieldVisitor} that generates a corresponding 'field_info' structure, as defined in the
 * Java Virtual Machine Specification (JVMS).
 *
 * @see JVMS
 *     4.5
 * @author Eric Bruneton
 */
final class FieldWriter extends FieldVisitor {

  /** Where the constants used in this FieldWriter must be stored. */
  private final SymbolTable symbolTable;

  // Note: fields are ordered as in the field_info structure, and those related to attributes are
  // ordered as in Section 4.7 of the JVMS.

  /**
   * The access_flags field of the field_info JVMS structure. This field can contain ASM specific
   * access flags, such as {@link Opcodes#ACC_DEPRECATED}, which are removed when generating the
   * ClassFile structure.
   */
  private final int accessFlags;

  /** The name_index field of the field_info JVMS structure. */
  private final int nameIndex;

  /** The descriptor_index field of the field_info JVMS structure. */
  private final int descriptorIndex;

  /**
   * The signature_index field of the Signature attribute of this field_info, or 0 if there is no
   * Signature attribute.
   */
  private int signatureIndex;

  /**
   * The constantvalue_index field of the ConstantValue attribute of this field_info, or 0 if there
   * is no ConstantValue attribute.
   */
  private int constantValueIndex;

  /**
   * The last runtime visible annotation of this field. The previous ones can be accessed with the
   * {@link AnnotationWriter#previousAnnotation} field. May be {@literal null}.
   */
  private AnnotationWriter lastRuntimeVisibleAnnotation;

  /**
   * The last runtime invisible annotation of this field. The previous ones can be accessed with the
   * {@link AnnotationWriter#previousAnnotation} field. May be {@literal null}.
   */
  private AnnotationWriter lastRuntimeInvisibleAnnotation;

  /**
   * The last runtime visible type annotation of this field. The previous ones can be accessed with
   * the {@link AnnotationWriter#previousAnnotation} field. May be {@literal null}.
   */
  private AnnotationWriter lastRuntimeVisibleTypeAnnotation;

  /**
   * The last runtime invisible type annotation of this field. The previous ones can be accessed
   * with the {@link AnnotationWriter#previousAnnotation} field. May be {@literal null}.
   */
  private AnnotationWriter lastRuntimeInvisibleTypeAnnotation;

  /**
   * The first non standard attribute of this field. The next ones can be accessed with the {@link
   * Attribute#nextAttribute} field. May be {@literal null}.
   *
   * 

WARNING: this list stores the attributes in the reverse order of their visit. * firstAttribute is actually the last attribute visited in {@link #visitAttribute}. The {@link * #putFieldInfo} method writes the attributes in the order defined by this list, i.e. in the * reverse order specified by the user. */ private Attribute firstAttribute; // ----------------------------------------------------------------------------------------------- // Constructor // ----------------------------------------------------------------------------------------------- /** * Constructs a new {@link FieldWriter}. * * @param symbolTable where the constants used in this FieldWriter must be stored. * @param access the field's access flags (see {@link Opcodes}). * @param name the field's name. * @param descriptor the field's descriptor (see {@link Type}). * @param signature the field's signature. May be {@literal null}. * @param constantValue the field's constant value. May be {@literal null}. */ FieldWriter( final SymbolTable symbolTable, final int access, final String name, final String descriptor, final String signature, final Object constantValue) { super(Opcodes.ASM7); this.symbolTable = symbolTable; this.accessFlags = access; this.nameIndex = symbolTable.addConstantUtf8(name); this.descriptorIndex = symbolTable.addConstantUtf8(descriptor); if (signature != null) { this.signatureIndex = symbolTable.addConstantUtf8(signature); } if (constantValue != null) { this.constantValueIndex = symbolTable.addConstant(constantValue).index; } } // ----------------------------------------------------------------------------------------------- // Implementation of the FieldVisitor abstract class // ----------------------------------------------------------------------------------------------- @Override public AnnotationVisitor visitAnnotation(final String descriptor, final boolean visible) { // Create a ByteVector to hold an 'annotation' JVMS structure. // See https://docs.oracle.com/javase/specs/jvms/se9/html/jvms-4.html#jvms-4.7.16. ByteVector annotation = new ByteVector(); // Write type_index and reserve space for num_element_value_pairs. annotation.putShort(symbolTable.addConstantUtf8(descriptor)).putShort(0); if (visible) { return lastRuntimeVisibleAnnotation = new AnnotationWriter(symbolTable, annotation, lastRuntimeVisibleAnnotation); } else { return lastRuntimeInvisibleAnnotation = new AnnotationWriter(symbolTable, annotation, lastRuntimeInvisibleAnnotation); } } @Override public AnnotationVisitor visitTypeAnnotation( final int typeRef, final TypePath typePath, final String descriptor, final boolean visible) { // Create a ByteVector to hold a 'type_annotation' JVMS structure. // See https://docs.oracle.com/javase/specs/jvms/se9/html/jvms-4.html#jvms-4.7.20. ByteVector typeAnnotation = new ByteVector(); // Write target_type, target_info, and target_path. TypeReference.putTarget(typeRef, typeAnnotation); TypePath.put(typePath, typeAnnotation); // Write type_index and reserve space for num_element_value_pairs. typeAnnotation.putShort(symbolTable.addConstantUtf8(descriptor)).putShort(0); if (visible) { return lastRuntimeVisibleTypeAnnotation = new AnnotationWriter(symbolTable, typeAnnotation, lastRuntimeVisibleTypeAnnotation); } else { return lastRuntimeInvisibleTypeAnnotation = new AnnotationWriter(symbolTable, typeAnnotation, lastRuntimeInvisibleTypeAnnotation); } } @Override public void visitAttribute(final Attribute attribute) { // Store the attributes in the reverse order of their visit by this method. attribute.nextAttribute = firstAttribute; firstAttribute = attribute; } @Override public void visitEnd() { // Nothing to do. } // ----------------------------------------------------------------------------------------------- // Utility methods // ----------------------------------------------------------------------------------------------- /** * Returns the size of the field_info JVMS structure generated by this FieldWriter. Also adds the * names of the attributes of this field in the constant pool. * * @return the size in bytes of the field_info JVMS structure. */ int computeFieldInfoSize() { // The access_flags, name_index, descriptor_index and attributes_count fields use 8 bytes. int size = 8; // For ease of reference, we use here the same attribute order as in Section 4.7 of the JVMS. if (constantValueIndex != 0) { // ConstantValue attributes always use 8 bytes. symbolTable.addConstantUtf8(Constants.CONSTANT_VALUE); size += 8; } // Before Java 1.5, synthetic fields are represented with a Synthetic attribute. if ((accessFlags & Opcodes.ACC_SYNTHETIC) != 0 && symbolTable.getMajorVersion() < Opcodes.V1_5) { // Synthetic attributes always use 6 bytes. symbolTable.addConstantUtf8(Constants.SYNTHETIC); size += 6; } if (signatureIndex != 0) { // Signature attributes always use 8 bytes. symbolTable.addConstantUtf8(Constants.SIGNATURE); size += 8; } // ACC_DEPRECATED is ASM specific, the ClassFile format uses a Deprecated attribute instead. if ((accessFlags & Opcodes.ACC_DEPRECATED) != 0) { // Deprecated attributes always use 6 bytes. symbolTable.addConstantUtf8(Constants.DEPRECATED); size += 6; } if (lastRuntimeVisibleAnnotation != null) { size += lastRuntimeVisibleAnnotation.computeAnnotationsSize( Constants.RUNTIME_VISIBLE_ANNOTATIONS); } if (lastRuntimeInvisibleAnnotation != null) { size += lastRuntimeInvisibleAnnotation.computeAnnotationsSize( Constants.RUNTIME_INVISIBLE_ANNOTATIONS); } if (lastRuntimeVisibleTypeAnnotation != null) { size += lastRuntimeVisibleTypeAnnotation.computeAnnotationsSize( Constants.RUNTIME_VISIBLE_TYPE_ANNOTATIONS); } if (lastRuntimeInvisibleTypeAnnotation != null) { size += lastRuntimeInvisibleTypeAnnotation.computeAnnotationsSize( Constants.RUNTIME_INVISIBLE_TYPE_ANNOTATIONS); } if (firstAttribute != null) { size += firstAttribute.computeAttributesSize(symbolTable); } return size; } /** * Puts the content of the field_info JVMS structure generated by this FieldWriter into the given * ByteVector. * * @param output where the field_info structure must be put. */ void putFieldInfo(final ByteVector output) { boolean useSyntheticAttribute = symbolTable.getMajorVersion() < Opcodes.V1_5; // Put the access_flags, name_index and descriptor_index fields. int mask = useSyntheticAttribute ? Opcodes.ACC_SYNTHETIC : 0; output.putShort(accessFlags & ~mask).putShort(nameIndex).putShort(descriptorIndex); // Compute and put the attributes_count field. // For ease of reference, we use here the same attribute order as in Section 4.7 of the JVMS. int attributesCount = 0; if (constantValueIndex != 0) { ++attributesCount; } if ((accessFlags & Opcodes.ACC_SYNTHETIC) != 0 && useSyntheticAttribute) { ++attributesCount; } if (signatureIndex != 0) { ++attributesCount; } if ((accessFlags & Opcodes.ACC_DEPRECATED) != 0) { ++attributesCount; } if (lastRuntimeVisibleAnnotation != null) { ++attributesCount; } if (lastRuntimeInvisibleAnnotation != null) { ++attributesCount; } if (lastRuntimeVisibleTypeAnnotation != null) { ++attributesCount; } if (lastRuntimeInvisibleTypeAnnotation != null) { ++attributesCount; } if (firstAttribute != null) { attributesCount += firstAttribute.getAttributeCount(); } output.putShort(attributesCount); // Put the field_info attributes. // For ease of reference, we use here the same attribute order as in Section 4.7 of the JVMS. if (constantValueIndex != 0) { output .putShort(symbolTable.addConstantUtf8(Constants.CONSTANT_VALUE)) .putInt(2) .putShort(constantValueIndex); } if ((accessFlags & Opcodes.ACC_SYNTHETIC) != 0 && useSyntheticAttribute) { output.putShort(symbolTable.addConstantUtf8(Constants.SYNTHETIC)).putInt(0); } if (signatureIndex != 0) { output .putShort(symbolTable.addConstantUtf8(Constants.SIGNATURE)) .putInt(2) .putShort(signatureIndex); } if ((accessFlags & Opcodes.ACC_DEPRECATED) != 0) { output.putShort(symbolTable.addConstantUtf8(Constants.DEPRECATED)).putInt(0); } if (lastRuntimeVisibleAnnotation != null) { lastRuntimeVisibleAnnotation.putAnnotations( symbolTable.addConstantUtf8(Constants.RUNTIME_VISIBLE_ANNOTATIONS), output); } if (lastRuntimeInvisibleAnnotation != null) { lastRuntimeInvisibleAnnotation.putAnnotations( symbolTable.addConstantUtf8(Constants.RUNTIME_INVISIBLE_ANNOTATIONS), output); } if (lastRuntimeVisibleTypeAnnotation != null) { lastRuntimeVisibleTypeAnnotation.putAnnotations( symbolTable.addConstantUtf8(Constants.RUNTIME_VISIBLE_TYPE_ANNOTATIONS), output); } if (lastRuntimeInvisibleTypeAnnotation != null) { lastRuntimeInvisibleTypeAnnotation.putAnnotations( symbolTable.addConstantUtf8(Constants.RUNTIME_INVISIBLE_TYPE_ANNOTATIONS), output); } if (firstAttribute != null) { firstAttribute.putAttributes(symbolTable, output); } } /** * Collects the attributes of this field into the given set of attribute prototypes. * * @param attributePrototypes a set of attribute prototypes. */ final void collectAttributePrototypes(final Attribute.Set attributePrototypes) { attributePrototypes.addAttributes(firstAttribute); } }





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