dataflavor.java

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     * <code>java.lang.String</code>, <code>java.nio.CharBuffer</code>, or
     * <code>[C</code>, the <code>charset</code> parameter must also be equal.
     * If a charset is not explicitly specified for one or both
     * <code>DataFlavor</code>s, the platform default encoding is assumed. See
     * <code>selectBestTextFlavor</code> for a list of text flavors which
     * support the charset parameter.
     *
     * @param that the <code>DataFlavor</code> to compare with
     *        <code>this</code>
     * @return <code>true</code> if <code>that</code> is equivalent to this
     *         <code>DataFlavor</code>; <code>false</code> otherwise
     * @see #selectBestTextFlavor
     */
    public boolean match(DataFlavor that) {
	return equals(that);
    }
    
    /**
     * Returns whether the string representation of the MIME type passed in
     * is equivalent to the MIME type of this <code>DataFlavor</code>.
     * Parameters are not included in the comparison.
     *
     * @param mimeType the string representation of the MIME type
     * @return true if the string representation of the MIME type passed in is
     *         equivalent to the MIME type of this <code>DataFlavor</code>;
     *         false otherwise
     * @throws NullPointerException if mimeType is <code>null</code>
     */
    public boolean isMimeTypeEqual(String mimeType) {
	// JCK Test DataFlavor0117: if 'mimeType' is null, throw NPE
	if (mimeType == null) {
	    throw new NullPointerException("mimeType");
	}
        if (this.mimeType == null) {
            return false;
        }
        try {
            return this.mimeType.match(new MimeType(mimeType));
        } catch (MimeTypeParseException mtpe) {
            return false; 
        }
    }
    
    /**
     * Compares the <code>mimeType</code> of two <code>DataFlavor</code>
     * objects. No parameters are considered.
     *
     * @param dataFlavor the <code>DataFlavor</code> to be compared
     * @return true if the <code>MimeType</code>s are equal,
     *	otherwise false
     */
    
    public final boolean isMimeTypeEqual(DataFlavor dataFlavor) {
        return isMimeTypeEqual(dataFlavor.mimeType);
    }
    
    /**
     * Compares the <code>mimeType</code> of two <code>DataFlavor</code>
     * objects.  No parameters are considered.
     *
     * @return true if the <code>MimeType</code>s are equal,
     *	otherwise false
     */
    
    private boolean isMimeTypeEqual(MimeType mtype) {
        if (this.mimeType == null) {
            return (mtype == null);
        }
        return mimeType.match(mtype);
    }

   /**
    * Does the <code>DataFlavor</code> represent a serialized object?
    */

    public boolean isMimeTypeSerializedObject() {
        return isMimeTypeEqual(javaSerializedObjectMimeType);
    }

    public final Class getDefaultRepresentationClass() {
        return ioInputStreamClass;
    }

    public final String getDefaultRepresentationClassAsString() {
        return getDefaultRepresentationClass().getName();
    }

   /**
    * Does the <code>DataFlavor</code> represent a 
    * <code>java.io.InputStream</code>?
    */

    public boolean isRepresentationClassInputStream() {
        return ioInputStreamClass.isAssignableFrom(representationClass);
    }

    /**
     * Returns whether the representation class for this
     * <code>DataFlavor</code> is <code>java.io.Reader</code> or a subclass
     * thereof.
     *
     * @since 1.4
     */
    public boolean isRepresentationClassReader() {
	return java.io.Reader.class.isAssignableFrom(representationClass);
    }

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

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

   /**
    * Returns true if the representation class can be serialized.
    * @return true if the representation class can be serialized
    */

    public boolean isRepresentationClassSerializable() {
        return java.io.Serializable.class.isAssignableFrom(representationClass);
    }

   /**
    * Returns true if the representation class is <code>Remote</code>.
    * @return true if the representation class is <code>Remote</code>
    */

    public boolean isRepresentationClassRemote() {
        return java.rmi.Remote.class.isAssignableFrom(representationClass);
    }

   /**
    * Returns true if the <code>DataFlavor</code> specified represents
    * a serialized object.
    * @return true if the <code>DataFlavor</code> specified represents
    *	a Serialized Object
    */

    public boolean isFlavorSerializedObjectType() {
        return isRepresentationClassSerializable() && isMimeTypeEqual(javaSerializedObjectMimeType);
    }

    /**
     * Returns true if the <code>DataFlavor</code> specified represents
     * a remote object.
     * @return true if the <code>DataFlavor</code> specified represents
     *	a Remote Object
     */
  
    public boolean isFlavorRemoteObjectType() {
        return isRepresentationClassRemote() 
            && isRepresentationClassSerializable() 
            && isMimeTypeEqual(javaRemoteObjectMimeType);
    }

  
   /**
    * Returns true if the <code>DataFlavor</code> specified represents
    * a list of file objects.
    * @return true if the <code>DataFlavor</code> specified represents
    *	a List of File objects
    */

   public boolean isFlavorJavaFileListType() {
        if (mimeType == null || representationClass == null)
            return false;
        return java.util.List.class.isAssignableFrom(representationClass) &&
               mimeType.match(javaFileListFlavor.mimeType);

   }

    /**
     * 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>[C</code>,
     * <code>java.io.InputStream</code>, <code>java.nio.ByteBuffer</code>, or
     * <code>[B</code>. If the representation is
     * <code>java.io.InputStream</code>, <code>java.nio.ByteBuffer</code>, or
     * <code>[B</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>, or <code>[B</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() { 
        return (DataTransferer.isFlavorCharsetTextType(this) ||
                DataTransferer.isFlavorNoncharsetTextType(this));
    }

   /**
    * Serializes this <code>DataFlavor</code>.
    */

   public synchronized void writeExternal(ObjectOutput os) throws IOException {
       if (mimeType != null) {
           mimeType.setParameter("humanPresentableName", humanPresentableName);
           os.writeObject(mimeType);
           mimeType.removeParameter("humanPresentableName");
       } else {
           os.writeObject(null);
       }

       os.writeObject(representationClass);
   }

   /**
    * Restores this <code>DataFlavor</code> from a Serialized state.
    */

   public synchronized void readExternal(ObjectInput is) throws IOException , ClassNotFoundException {
	String rcn = null;
        mimeType = (MimeType)is.readObject();

        if (mimeType != null) {
            humanPresentableName =
                mimeType.getParameter("humanPresentableName");
            mimeType.removeParameter("humanPresentableName");
            rcn = mimeType.getParameter("class");
            if (rcn == null) {
                throw new IOException("no class parameter specified in: " +
                                      mimeType);
            }
        }

	try {
            representationClass = (Class)is.readObject();
        } catch (OptionalDataException ode) {
            if (rcn != null) {
                representationClass =
                    DataFlavor.tryToLoadClass(rcn, getClass().getClassLoader());
            }
        }
   }

   /**
    * Returns a clone of this <code>DataFlavor</code>.
    * @return a clone of this <code>DataFlavor</code>
    */

    public Object clone() throws CloneNotSupportedException {
	Object newObj = super.clone();
	if (mimeType != null) {
	    ((DataFlavor)newObj).mimeType = (MimeType)mimeType.clone();
	}
	return newObj;
    } // clone()

   /**
    * Called on <code>DataFlavor</code> for every MIME Type parameter
    * to allow <code>DataFlavor</code> subclasses to handle special
    * parameters like the text/plain <code>charset</code>
    * parameters, whose values are case insensitive.  (MIME type parameter
    * values are supposed to be case sensitive.
    * <p>
    * This method is called for each parameter name/value pair and should
    * return the normalized representation of the <code>parameterValue</code>.
    *
    * This method is never invoked by this implementation from 1.1 onwards.
    *
    * @deprecated
    */
    protected String normalizeMimeTypeParameter(String parameterName, String parameterValue) {
        return parameterValue;        
    }
  
   /**
    * Called for each MIME type string to give <code>DataFlavor</code> subtypes 
    * the opportunity to change how the normalization of MIME types is 
    * accomplished.  One possible use would be to add default
    * parameter/value pairs in cases where none are present in the MIME
    * type string passed in.
    *
    * This method is never invoked by this implementation from 1.1 onwards.
    *
    * @deprecated
    */
    protected String normalizeMimeType(String mimeType) {
        return mimeType;        
    }

    /*
     * fields
     */

    /* placeholder for caching any platform-specific data for flavor */

    transient int       atom;      
  
    /* Mime Type of DataFlavor */

    MimeType            mimeType;

    private String      humanPresentableName;  
  
    /** Java class of objects this DataFlavor represents **/

    private Class       representationClass;

} // class DataFlavor