dataflavor.java

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  {
    if ("humanPresentableName".equals(paramName))
      return getHumanPresentableName();
  
    return getParameter(paramName, mimeType);
  }

  /**
   * Sets the human presentable name to the specified value.
   *
   * @param humanPresentableName The new display name.
   */
  public void setHumanPresentableName(String humanPresentableName)
  {
    this.humanPresentableName = humanPresentableName;
  }

  /**
   * Tests the MIME type of this object for equality against the specified
   * MIME type. Ignores parameters.
   *
   * @param mimeType The MIME type to test against.
   *
   * @return <code>true</code> if the MIME type is equal to this object's
   * MIME type (ignoring parameters), <code>false</code> otherwise.
   *
   * @exception NullPointerException If mimeType is null.
   */
  public boolean isMimeTypeEqual(String mimeType)
  {
    String mime = getMimeType();
    int i = mime.indexOf(";");
    if (i != -1)
      mime = mime.substring(0, i);
  
    i = mimeType.indexOf(";");
    if (i != -1)
      mimeType = mimeType.substring(0, i);
  
    return mime.equals(mimeType);
  }

  /**
   * Tests the MIME type of this object for equality against the specified
   * data flavor's MIME type
   *
   * @param flavor The flavor to test against.
   *
   * @return <code>true</code> if the flavor's MIME type is equal to this 
   * object's MIME type, <code>false</code> otherwise.
   */
  public final boolean isMimeTypeEqual(DataFlavor flavor)
  {
    return isMimeTypeEqual(flavor.getMimeType());
  }

  /**
   * Tests whether or not this flavor represents a serialized object.
   *
   * @return <code>true</code> if this flavor represents a serialized
   * object, <code>false</code> otherwise.
   */
  public boolean isMimeTypeSerializedObject()
  {
    return mimeType.startsWith(javaSerializedObjectMimeType);
  }

  /**
   * Tests whether or not this flavor has a representation class of
   * <code>java.io.InputStream</code>.
   *
   * @return <code>true</code> if the representation class of this flavor
   * is <code>java.io.InputStream</code>, <code>false</code> otherwise.
   */
  public boolean isRepresentationClassInputStream()
  {
    return representationClass.getName().equals("java.io.InputStream");
  }

  /**
   * Tests whether the representation class for this flavor is
   * serializable.
   *
   * @return <code>true</code> if the representation class is serializable,
   * <code>false</code> otherwise.
   */
  public boolean isRepresentationClassSerializable()
  {
    Class[] interfaces = representationClass.getInterfaces();
  
    int i = 0;
    while (i < interfaces.length)
      {
        if (interfaces[i].getName().equals("java.io.Serializable"))
          return true;
        ++i;
      }
  
    return false;
  }

  /**
   * Tests whether the representation class for his flavor is remote.
   *
   * @return <code>true</code> if the representation class is remote,
   * <code>false</code> otherwise.
   */
  public boolean isRepresentationClassRemote()
  {
    return Remote.class.isAssignableFrom (representationClass);
  }

  /**
   * Tests whether or not this flavor represents a serialized object.
   *
   * @return <code>true</code> if this flavor represents a serialized
   * object, <code>false</code> otherwise.
   */
  public boolean isFlavorSerializedObjectType()
  {
    // FIXME: What is the diff between this and isMimeTypeSerializedObject?
    return(mimeType.startsWith(javaSerializedObjectMimeType));
  }

  /**
   * Tests whether or not this flavor represents a remote object.
   *
   * @return <code>true</code> if this flavor represents a remote object,
   * <code>false</code> otherwise.
   */
  public boolean isFlavorRemoteObjectType()
  {
    return(mimeType.startsWith(javaRemoteObjectMimeType));
  }

  /**
   * Tests whether or not this flavor represents a list of files.
   *
   * @return <code>true</code> if this flavor represents a list of files,
   * <code>false</code> otherwise.
   */
  public boolean isFlavorJavaFileListType()
  {
    if (mimeType.equals(javaFileListFlavor.mimeType)
        && representationClass.equals(javaFileListFlavor.representationClass))
      return true;
  
    return false ;
  }

  /**
   * Returns a copy of this object.
   *
   * @return A copy of this object.
   *
   * @exception CloneNotSupportedException If the object's class does not support
   * the Cloneable interface. Subclasses that override the clone method can also
   * throw this exception to indicate that an instance cannot be cloned.
   */
  public Object clone () throws CloneNotSupportedException
  {
    // FIXME - This cannot be right.
    try
      {
        return super.clone();
      }
    catch(Exception e)
      {
        return null;
      }
  }

  /**
   * This method test the specified <code>DataFlavor</code> for equality
   * against this object.  This will be true if the MIME type and
   * representation type are the equal.
   *
   * @param flavor The <code>DataFlavor</code> to test against.
   *
   * @return <code>true</code> if the flavor is equal to this object,
   * <code>false</code> otherwise.
   */
  public boolean equals(DataFlavor flavor)
  {
    if (flavor == null)
      return false;
  
    if (! this.mimeType.toLowerCase().equals(flavor.mimeType.toLowerCase()))
      return false;
  
    if (! this.representationClass.equals(flavor.representationClass))
      return false;
  
    return true;
  }

  /**
   * This method test the specified <code>Object</code> for equality
   * against this object.  This will be true if the following conditions
   * are met:
   * <p>
   * <ul>
   * <li>The object is not <code>null</code>.</li>
   * <li>The object is an instance of <code>DataFlavor</code>.</li>
   * <li>The object's MIME type and representation class are equal to
   * this object's.</li>
   * </ul>
   *
   * @param obj The <code>Object</code> to test against.
   *
   * @return <code>true</code> if the flavor is equal to this object,
   * <code>false</code> otherwise.
   */
  public boolean equals(Object obj)
  {
    if (! (obj instanceof DataFlavor))
      return false;
  
    return equals((DataFlavor) obj);
  }

  /**
   * Tests whether or not the specified string is equal to the MIME type
   * of this object.
   *
   * @param str The string to test against.
   *
   * @return <code>true</code> if the string is equal to this object's MIME
   * type, <code>false</code> otherwise.
   *
   * @deprecated Not compatible with <code>hashCode()</code>.
   *             Use <code>isMimeTypeEqual()</code>
   */
  public boolean equals(String str)
  {
    return isMimeTypeEqual(str);
  }

  /**
   * Returns the hash code for this data flavor.
   * The hash code is based on the (lower case) mime type and the
   * representation class.
   */
  public int hashCode()
  {
    return mimeType.toLowerCase().hashCode() ^ representationClass.hashCode();
  }

  /**
   * Returns <code>true</code> when the given <code>DataFlavor</code>
   * matches this one.
   */
  public boolean match(DataFlavor dataFlavor)
  {
    // XXX - How is this different from equals?
    return equals(dataFlavor);
  }

  /**
   * This method exists for backward compatibility.  It simply returns
   * the same name/value pair passed in.
   *
   * @param name The parameter name.
   * @param value The parameter value.
   *
   * @return The name/value pair.
   *
   * @deprecated
   */
  protected String normalizeMimeTypeParameter(String name, String value)
  {
    return name + "=" + value;
  }

  /**
   * This method exists for backward compatibility.  It simply returns
   * the MIME type string unchanged.
   *
   * @param type The MIME type.
   * 
   * @return The MIME type.
   *
   * @deprecated
   */
  protected String normalizeMimeType(String type)
  {
    return type;
  }

  /**
   * Serialize this class.
   *
   * @param stream The <code>ObjectOutput</code> stream to serialize to.
   *
   * @exception IOException If an error occurs.
   */
  public void writeExternal(ObjectOutput stream) throws IOException
  {
    // FIXME: Implement me
  }


  /**
   * De-serialize this class.
   *
   * @param stream The <code>ObjectInput</code> stream to deserialize from.
   *
   * @exception IOException If an error ocurs.
   * @exception ClassNotFoundException If the class for an object being restored
   * cannot be found.
   */
  public void readExternal(ObjectInput stream) 
    throws IOException, ClassNotFoundException
  {
    // FIXME: Implement me
  }

  /**
   * Returns a string representation of this DataFlavor. Including the
   * representation class name, MIME type and human presentable name.
   */
  public String toString()
  {
    return (getClass().getName()
           + "[representationClass=" + getRepresentationClass().getName()
           + ",mimeType=" + getMimeType()
           + ",humanPresentableName=" + getHumanPresentableName()
           + "]");
  }

  /**
   * XXX - Currently returns <code>java.io.InputStream</code>.
   *
   * @since 1.3
   */
  public final Class getDefaultRepresentationClass()
  {
    return java.io.InputStream.class;
  }

  /**
   * XXX - Currently returns <code>java.io.InputStream</code>.
   */
  public final String getDefaultRepresentationClassAsString()
  {
    return getDefaultRepresentationClass().getName();
  }

  /**
   * Creates a <code>Reader</code> for a given <code>Transferable</code>.
   *
   * If the representation class is a (subclass of) <code>Reader</code>
   * then an instance of the representation class is returned. If the
   * representatation class is a <code>String</code> then a
   * <code>StringReader</code> is returned. And if the representation class
   * is a (subclass of) <code>InputStream</code> and the primary MIME type
   * is "text" then a <code>InputStreamReader</code> for the correct charset
   * encoding is returned.
   *
   * @param transferable The <code>Transferable</code> for which a text
   *                     <code>Reader</code> is requested.
   *
   * @exception IllegalArgumentException If the representation class is not one
   * of the seven listed above or the Transferable has null data.
   * @exception NullPointerException If the Transferable is null.
   * @exception UnsupportedFlavorException when the transferable doesn't
   * support this <code>DataFlavor</code>. Or if the representable class
   * isn't a (subclass of) <code>Reader</code>, <code>String</code>,
   * <code>InputStream</code> and/or the primary MIME type isn't "text".
   * @exception IOException when any IOException occurs.
   * @exception UnsupportedEncodingException if the "charset" isn't supported
   * on this platform.
   */
  public Reader getReaderForText(Transferable transferable)
    throws UnsupportedFlavorException, IOException
  {
      if (!transferable.isDataFlavorSupported(this))
          throw new UnsupportedFlavorException(this);
  
      if (Reader.class.isAssignableFrom(representationClass))
          return (Reader)transferable.getTransferData(this);
  
      if (String.class.isAssignableFrom(representationClass))
          return new StringReader((String)transferable.getTransferData(this));
  
      if (InputStream.class.isAssignableFrom(representationClass)
          && "text".equals(getPrimaryType()))
        {
          InputStream in = (InputStream)transferable.getTransferData(this);
          String encoding = getParameter("charset");
          if (encoding == null)
              encoding = "us-ascii";
          return new InputStreamReader(in, encoding);
        }
  
      throw new UnsupportedFlavorException(this);
  }

  /**
   * Returns whether the representation class for this DataFlavor is
   * @see java.nio.ByteBuffer or a subclass thereof.
   *
   * @since 1.4
   */
  public boolean isRepresentationClassByteBuffer()
  {
    return ByteBuffer.class.isAssignableFrom(representationClass);
  }

  /**
   * Returns whether the representation class for this DataFlavor is
   * @see java.nio.CharBuffer or a subclass thereof.
   *
   * @since 1.4
   */
  public boolean isRepresentationClassCharBuffer()
  {
    return CharBuffer.class.isAssignableFrom(representationClass);
  }

  /**
   * Returns whether the representation class for this DataFlavor is
   * @see java.io.Reader or a subclass thereof.
   *
   * @since 1.4
   */
  public boolean isRepresentationClassReader()
  {
    return Reader.class.isAssignableFrom(representationClass);
  }
  
  /**
   * Returns whether this <code>DataFlavor</code> is a valid text flavor for
   * this implementation of the Java platform. Only flavors equivalent to
   * <code>DataFlavor.stringFlavor</code> and <code>DataFlavor</code>s with
   * a primary MIME type of "text" can be valid text flavors.
   * <p>
   * If this flavor supports the charset parameter, it must be equivalent to
   * <code>DataFlavor.stringFlavor</code>, or its representation must be
   * <code>java.io.Reader</code>, <code>java.lang.String</code>,
   * <code>java.nio.CharBuffer</code>, <code>java.io.InputStream</code> or 
   * <code>java.nio.ByteBuffer</code>,
   * If the representation is <code>java.io.InputStream</code> or 
   * <code>java.nio.ByteBuffer</code>, then this flavor's <code>charset</code> 
   * parameter must be supported by this implementation of the Java platform. 
   * If a charset is not specified, then the platform default charset, which 
   * is always supported, is assumed.
   * <p>
   * If this flavor does not support the charset parameter, its
   * representation must be <code>java.io.InputStream</code>,
   * <code>java.nio.ByteBuffer</code>.
   * <p>
   * See <code>selectBestTextFlavor</code> for a list of text flavors which
   * support the charset parameter.
   *
   * @return <code>true</code> if this <code>DataFlavor</code> is a valid
   *         text flavor as described above; <code>false</code> otherwise
   * @see #selectBestTextFlavor
   * @since 1.4
   */
  public boolean isFlavorTextType() {
    // FIXME: I'm not 100% sure if this implementation does the same like sun's does    
    if(equals(DataFlavor.stringFlavor) || getPrimaryType().equals("text"))
      {
        String charset = getParameter("charset");
        Class c = getRepresentationClass();
        if(charset != null) 
          {            
            if(Reader.class.isAssignableFrom(c) 
                || CharBuffer.class.isAssignableFrom(c) 
                || String.class.isAssignableFrom(c)) 
              {
                return true;
              }
            else if(InputStream.class.isAssignableFrom(c)
                    || ByteBuffer.class.isAssignableFrom(c))
              {
                return Charset.isSupported(charset);
              }
          }
        else if(InputStream.class.isAssignableFrom(c)
            || ByteBuffer.class.isAssignableFrom(c))
          {
            return true;
          }
      }
    return false;
  }
} // class DataFlavor