如何使用Sharpen转换Java Enum

Question

我试图使用来自versant的sharpen转换器将未绑定的id ldap java sdk源代码转换为c＃。 但是，我得到一个与java枚举类相关的异常，它有几个构造函数，看起来与普通的 .NET枚举不同。

错误消息如下：

ERROR: /sharpened/src/com/unboundid/asn1/ASN1Messages.java:240: Enum can contain
only fields and a private constructor.

java类如下所示：

enum ASN1Messages
{
  /**
   * ASN.1 Boolean elements must have a value whose length is exactly one byte.
   */
  ERR_BOOLEAN_INVALID_LENGTH("ASN.1 Boolean elements must have a value whose length is exactly one byte."),



  /**
   * Unable to decode the provided byte array as an ASN.1 BER element:  {0}
   */
  ERR_ELEMENT_DECODE_EXCEPTION("Unable to decode the provided byte array as an ASN.1 BER element:  {0}"),

这个课程中有问题的方法是：

/**
   * Retrieves a localized version of the message.
   * This method should only be used for messages which do not take any arguments.
   *
   * @return  A localized version of the message.
   */
  public String get()
  {
    String s = MESSAGE_STRINGS.get(this);
    if (s == null)
    {

使用锐化工具克服此问题的最佳方法是什么？

完整的类文件源代码如下：

/ * *版权所有2012 UnboundID Corp. *保留所有权利。 / / *版权所有（C）2012 UnboundID Corp. * *此程序是免费软件; 您可以根据GNU通用公共许可证（仅限GPLv2）*或自由软件基金会发布的GNU宽通用公共许可证（仅限LGPLv2.1）*的条款重新分发和/或修改*。 * *本程序的发布是希望它有用，*但没有任何担保; 甚至没有*适销性或特定用途适用性的暗示保证。 有关更多详细信息，请参阅* GNU通用公共许可证。 * *您应该已收到GNU通用公共许可证*的副本以及此程序; 如果没有，请参阅http://www.gnu.org/licenses 。 * / package com.unboundid.asn1;

import java.text.MessageFormat;
import java.util.ResourceBundle;
import java.util.concurrent.ConcurrentHashMap;



/**
 * This enum defines a set of message keys for messages in the
 * com.unboundid.asn1 package, which correspond to messages in the
 * unboundid-ldapsdk-asn1.properties properties file.
 * <BR><BR>
 * This source file was generated from the properties file.
 * Do not edit it directly.
 */
enum ASN1Messages
{
  /**
   * ASN.1 Boolean elements must have a value whose length is exactly one byte.
   */
  ERR_BOOLEAN_INVALID_LENGTH("ASN.1 Boolean elements must have a value whose length is exactly one byte."),



  /**
   * Unable to decode the provided byte array as an ASN.1 BER element:  {0}
   */
  ERR_ELEMENT_DECODE_EXCEPTION("Unable to decode the provided byte array as an ASN.1 BER element:  {0}"),



  /**
   * The decoded length of {0,number,0} does not match the number of bytes remaining in the provided array ({1,number,0}).
   */
  ERR_ELEMENT_LENGTH_MISMATCH("The decoded length of {0,number,0} does not match the number of bytes remaining in the provided array ({1,number,0})."),



  /**
   * Invalid value length of {0,number,0} for an ASN.1 enumerated element.  Enumerated element values must have a length between 1 and 4 bytes.
   */
  ERR_ENUMERATED_INVALID_LENGTH("Invalid value length of {0,number,0} for an ASN.1 enumerated element.  Enumerated element values must have a length between 1 and 4 bytes."),



  /**
   * Invalid value length of {0,number,0} for an ASN.1 integer element.  Integer element values must have a length between 1 and 4 bytes.
   */
  ERR_INTEGER_INVALID_LENGTH("Invalid value length of {0,number,0} for an ASN.1 integer element.  Integer element values must have a length between 1 and 4 bytes."),



  /**
   * Invalid value length of {0,number,0} for an ASN.1 long element.  Long element values must have a length between 1 and 8 bytes.
   */
  ERR_LONG_INVALID_LENGTH("Invalid value length of {0,number,0} for an ASN.1 long element.  Long element values must have a length between 1 and 8 bytes."),



  /**
   * ASN.1 null elements must not have a value.
   */
  ERR_NULL_HAS_VALUE("ASN.1 null elements must not have a value."),



  /**
   * The end of the input stream was reached before the first length byte could be read.
   */
  ERR_READ_END_BEFORE_FIRST_LENGTH("The end of the input stream was reached before the first length byte could be read."),



  /**
   * The end of the input stream was reached before the full length could be read.
   */
  ERR_READ_END_BEFORE_LENGTH_END("The end of the input stream was reached before the full length could be read."),



  /**
   * The end of the input stream was reached before the full value could be read.
   */
  ERR_READ_END_BEFORE_VALUE_END("The end of the input stream was reached before the full value could be read."),



  /**
   * The element indicated that it required {0,number,0} bytes to hold the value, but this is larger than the maximum of {1,number,0} bytes that the client has been configured to accept.
   */
  ERR_READ_LENGTH_EXCEEDS_MAX("The element indicated that it required {0,number,0} bytes to hold the value, but this is larger than the maximum of {1,number,0} bytes that the client has been configured to accept."),



  /**
   * The element indicated that it required {0,number,0} bytes to encode the multi-byte length, but multi-byte lengths must be encoded in 1 to 4 bytes.
   */
  ERR_READ_LENGTH_TOO_LONG("The element indicated that it required {0,number,0} bytes to encode the multi-byte length, but multi-byte lengths must be encoded in 1 to 4 bytes."),



  /**
   * Unable to decode the provided byte array as a sequence:  {0}
   */
  ERR_SEQUENCE_BYTES_DECODE_EXCEPTION("Unable to decode the provided byte array as a sequence:  {0}"),



  /**
   * Unable to decode the provided byte array as a sequence because the decoded length of an embedded element exceeds the number of bytes remaining.
   */
  ERR_SEQUENCE_BYTES_DECODE_LENGTH_EXCEEDS_AVAILABLE("Unable to decode the provided byte array as a sequence because the decoded length of an embedded element exceeds the number of bytes remaining."),



  /**
   * Unable to decode the provided ASN.1 element {0} as a sequence:  {1}
   */
  ERR_SEQUENCE_DECODE_EXCEPTION("Unable to decode the provided ASN.1 element {0} as a sequence:  {1}"),



  /**
   * Unable to decode the provided ASN.1 element {0} as a sequence because the decoded length of an embedded element exceeds the number of bytes remaining.
   */
  ERR_SEQUENCE_DECODE_LENGTH_EXCEEDS_AVAILABLE("Unable to decode the provided ASN.1 element {0} as a sequence because the decoded length of an embedded element exceeds the number of bytes remaining."),



  /**
   * Unable to decode the provided byte array as a set:  {0}
   */
  ERR_SET_BYTES_DECODE_EXCEPTION("Unable to decode the provided byte array as a set:  {0}"),



  /**
   * Unable to decode the provided byte array as a set because the decoded length of an embedded element exceeds the number of bytes remaining.
   */
  ERR_SET_BYTES_DECODE_LENGTH_EXCEEDS_AVAILABLE("Unable to decode the provided byte array as a set because the decoded length of an embedded element exceeds the number of bytes remaining."),



  /**
   * Unable to decode the provided ASN.1 element {0} as a set:  {1}
   */
  ERR_SET_DECODE_EXCEPTION("Unable to decode the provided ASN.1 element {0} as a set:  {1}"),



  /**
   * Unable to decode the provided ASN.1 element {0} as a set because the decoded length of an embedded element exceeds the number of bytes remaining.
   */
  ERR_SET_DECODE_LENGTH_EXCEEDS_AVAILABLE("Unable to decode the provided ASN.1 element {0} as a set because the decoded length of an embedded element exceeds the number of bytes remaining."),



  /**
   * The ASN.1 stream reader has already read beyond the end of this sequence (expected sequence of length {0} to end at {1} bytes into the stream, but {2} bytes have already been read from the stream).
   */
  ERR_STREAM_READER_SEQUENCE_READ_PAST_END("The ASN.1 stream reader has already read beyond the end of this sequence (expected sequence of length {0} to end at {1} bytes into the stream, but {2} bytes have already been read from the stream)."),



  /**
   * The ASN.1 stream reader has already read beyond the end of this set (expected set of length {0} to end at {1} bytes into the stream, but {2} bytes have already been read from the stream).
   */
  ERR_STREAM_READER_SET_READ_PAST_END("The ASN.1 stream reader has already read beyond the end of this set (expected set of length {0} to end at {1} bytes into the stream, but {2} bytes have already been read from the stream).");



  /**
   * The resource bundle that will be used to load the properties file.
   */
  private static final ResourceBundle RESOURCE_BUNDLE;
  static
  {
    ResourceBundle rb = null;
    try
    {
      rb = ResourceBundle.getBundle("unboundid-ldapsdk-asn1");
    } catch (Exception e) {}
    RESOURCE_BUNDLE = rb;
  }



  /**
   * The map that will be used to hold the unformatted message strings, indexed by property name.
   */
  private static final ConcurrentHashMap<ASN1Messages,String> MESSAGE_STRINGS = new ConcurrentHashMap<ASN1Messages,String>();



  /**
   * The map that will be used to hold the message format objects, indexed by property name.
   */
  private static final ConcurrentHashMap<ASN1Messages,MessageFormat> MESSAGES = new ConcurrentHashMap<ASN1Messages,MessageFormat>();



  // The default text for this message
  private final String defaultText;



  /**
   * Creates a new message key.
   */
  private ASN1Messages(final String defaultText)
  {
    this.defaultText = defaultText;
  }



  /**
   * Retrieves a localized version of the message.
   * This method should only be used for messages which do not take any arguments.
   *
   * @return  A localized version of the message.
   */
  public String get()
  {
    String s = MESSAGE_STRINGS.get(this);
    if (s == null)
    {
      if (RESOURCE_BUNDLE == null)
      {
        return defaultText;
      }
      else
      {
        try
        {
          s = RESOURCE_BUNDLE.getString(name());
        }
        catch (final Exception e)
        {
          s = defaultText;
        }
        MESSAGE_STRINGS.putIfAbsent(this, s);
      }
    }
    return s;
  }



  /**
   * Retrieves a localized version of the message.
   *
   * @param  args  The arguments to use to format the message.
   *
   * @return  A localized version of the message.
   */
  public String get(final Object... args)
  {
    MessageFormat f = MESSAGES.get(this);
    if (f == null)
    {
      if (RESOURCE_BUNDLE == null)
      {
        f = new MessageFormat(defaultText);
      }
      else
      {
        try
        {
          f = new MessageFormat(RESOURCE_BUNDLE.getString(name()));
        }
        catch (final Exception e)
        {
          f = new MessageFormat(defaultText);
        }
      }
      MESSAGES.putIfAbsent(this, f);
    }
    synchronized (f)
    {
      return f.format(args);
    }
  }



  /**
   * Retrieves a string representation of this message key.
   *
   * @return  A string representation of this message key.
   */
  @Override()
  public String toString()
  {
    return get();
  }
}

Answer 1

我想知道Sharpen是否支持这样的枚举实现。 这是源代码，根据我的理解，只要在枚举中找到公共方法，它就会抛出异常：

private boolean processEnumType(TypeDeclaration node) {
    if (!isEnum(node)) {
        return false;
    }
    final CSEnum theEnum = new CSEnum(typeName(node));
    mapVisibility(node, theEnum);
    mapJavadoc(node, theEnum);
    addType(theEnum);

    node.accept(new ASTVisitor() {
        public boolean visit(VariableDeclarationFragment node) {
            theEnum.addValue(identifier(node.getName()));
            return false;
        }

        @Override
        public boolean visit(MethodDeclaration node) {
            if (node.isConstructor() && isPrivate(node)) {
                return false;
            }
            unsupportedConstruct(node, "Enum can contain only fields and a private constructor.");
            return false;
        }
    });
    return true;
}

但是 ，这个链接http://tracker.db4o.com/browse/COR-496似乎证实这适用于公众吸气者。 也就是说，如果你尊重这种结构：

enum ASN1Messages {
    /**
     * ASN.1 Boolean elements must have a value whose length is exactly one byte.
     */
    ERR_BOOLEAN_INVALID_LENGTH("ASN.1 Boolean elements must have a value whose length is exactly one byte."),


    /**
     * Unable to decode the provided byte array as an ASN.1 BER element:  {0}
     */
    ERR_ELEMENT_DECODE_EXCEPTION("Unable to decode the provided byte array as an ASN.1 BER element:  {0}"),;

    private String s;

    ASN1Messages(String s) {
        this.s = s;
    }

    /**
     * Retrieves a localized version of the message.
     * This method should only be used for messages which do not take any arguments.
     *
     * @return A localized version of the message.
     */
    public String get() {
        return s;
    }
}

Answer 2

根据你的枚举声明，你的枚举构造函数上有修饰符private 。 我认为这是无效的。 请尝试使用此构造函数：

ASN1Messages(final String defaultText) {
  this.defaultText = defaultText;
}

Answer 3

似乎包含get()方法以输出与每个枚举值对应的String 。

我在上面的代码上运行了Sharpen，但是注释掉了get()和toString()方法。 此转换成功，但与enum值关联的字符串不会传输到C＃文件。

因此，如果可以通过合理的努力来实现，我建议将Java代码拆分为不带关联字符串的纯 enum文件，以及一个静态帮助器类，其中包含用于enum String转换并实现get功能。

如果enum包含在重构的get方法签名中，

ASN1MessagesHelper.get(ASN1Messages mess)

通过修改获得的C＃代码，仍然可以模仿在enum上调用get()的Java功能：

ASN1MessagesHelper.Get(ASN1Messages mess) 
=> ASN1MessagesHelper.Get(this ASN1Messages mess)