001// ASM: a very small and fast Java bytecode manipulation framework
002// Copyright (c) 2000-2011 INRIA, France Telecom
003// All rights reserved.
004//
005// Redistribution and use in source and binary forms, with or without
006// modification, are permitted provided that the following conditions
007// are met:
008// 1. Redistributions of source code must retain the above copyright
009//    notice, this list of conditions and the following disclaimer.
010// 2. Redistributions in binary form must reproduce the above copyright
011//    notice, this list of conditions and the following disclaimer in the
012//    documentation and/or other materials provided with the distribution.
013// 3. Neither the name of the copyright holders nor the names of its
014//    contributors may be used to endorse or promote products derived from
015//    this software without specific prior written permission.
016//
017// THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS IS"
018// AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
019// IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
020// ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT OWNER OR CONTRIBUTORS BE
021// LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR
022// CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF
023// SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS
024// INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN
025// CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE)
026// ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF
027// THE POSSIBILITY OF SUCH DAMAGE.
028
029package io.ebean.enhance.asm.commons;
030
031import io.ebean.enhance.asm.ClassVisitor;
032import io.ebean.enhance.asm.Attribute;
033import io.ebean.enhance.asm.ByteVector;
034import io.ebean.enhance.asm.ClassReader;
035import io.ebean.enhance.asm.ClassWriter;
036import io.ebean.enhance.asm.Label;
037
038/**
039 * A ModuleTarget attribute. This attribute is specific to the OpenJDK and may change in the future.
040 *
041 * @author Remi Forax
042 */
043public final class ModuleTargetAttribute extends Attribute {
044
045  /** The name of the platform on which the module can run. */
046  public String platform;
047
048  /**
049   * Constructs a new {@link ModuleTargetAttribute}.
050   *
051   * @param platform the name of the platform on which the module can run.
052   */
053  public ModuleTargetAttribute(final String platform) {
054    super("ModuleTarget");
055    this.platform = platform;
056  }
057
058  /**
059   * Constructs an empty {@link ModuleTargetAttribute}. This object can be passed as a prototype to
060   * the {@link ClassReader#accept(ClassVisitor, Attribute[], int)} method.
061   */
062  public ModuleTargetAttribute() {
063    this(null);
064  }
065
066  @Override
067  protected Attribute read(
068      final ClassReader classReader,
069      final int offset,
070      final int length,
071      final char[] charBuffer,
072      final int codeOffset,
073      final Label[] labels) {
074    return new ModuleTargetAttribute(classReader.readUTF8(offset, charBuffer));
075  }
076
077  @Override
078  protected ByteVector write(
079      final ClassWriter classWriter,
080      final byte[] code,
081      final int codeLength,
082      final int maxStack,
083      final int maxLocals) {
084    ByteVector byteVector = new ByteVector();
085    byteVector.putShort(platform == null ? 0 : classWriter.newUTF8(platform));
086    return byteVector;
087  }
088}