* An instance of {@code DataFlavor} encapsulates a content type as defined in * RFC 2045 and * RFC 2046. A content type is * typically referred to as a MIME type. *
* A content type consists of a media type (referred to as the primary type), a * subtype, and optional parameters. See * RFC 2045 for details on the * syntax of a MIME type. *
* The JRE data transfer implementation interprets the parameter
* "class" of a MIME type as a representation class. The
* representation class reflects the class of the object being transferred. In
* other words, the representation class is the type of object returned by
* {@link Transferable#getTransferData}. For example, the MIME type of
* {@link #imageFlavor} is {@code "image/x-java-image;class=java.awt.Image"},
* the primary type is {@code image}, the subtype is {@code x-java-image}, and
* the representation class is {@code java.awt.Image}. When
* {@code getTransferData} is invoked with a {@code DataFlavor} of
* {@code imageFlavor}, an instance of {@code java.awt.Image} is returned. It's
* important to note that {@code DataFlavor} does no error checking against the
* representation class. It is up to consumers of {@code DataFlavor}, such as
* {@code Transferable}, to honor the representation class.
*
* Note, if you do not specify a representation class when creating a
* {@code DataFlavor}, the default representation class is used. See appropriate
* documentation for {@code DataFlavor}'s constructors.
*
* Also, {@code DataFlavor} instances with the "text" primary MIME * type may have a "charset" parameter. Refer to * RFC 2046 and * {@link #selectBestTextFlavor} for details on "text" MIME types and * the "charset" parameter. *
* Equality of {@code DataFlavors} is determined by the primary type, subtype, * and representation class. Refer to {@link #equals(DataFlavor)} for details. * When determining equality, any optional parameters are ignored. For example, * the following produces two {@code DataFlavors} that are considered identical: *
* DataFlavor flavor1 = new DataFlavor(Object.class, "X-test/test; class=<java.lang.Object>; foo=bar"); * DataFlavor flavor2 = new DataFlavor(Object.class, "X-test/test; class=<java.lang.Object>; x=y"); * // The following returns true. * flavor1.equals(flavor2); ** As mentioned, {@code flavor1} and {@code flavor2} are considered identical. * As such, asking a {@code Transferable} for either {@code DataFlavor} returns * the same results. *
* For more information on using data transfer with Swing see the
* How
* to Use Drag and Drop and Data Transfer, section in
* The Java Tutorial.
*
* @author Blake Sullivan
* @author Laurence P. G. Cable
* @author Jeff Dunn
* @since 1.1
*/
public class DataFlavor implements Externalizable, Cloneable {
private static final long serialVersionUID = 8367026044764648243L;
private static final Class
* The representation class associated with this {@code DataFlavor}
* identifies the Java type of an object returned as a reference from an
* invocation {@code java.awt.datatransfer.getTransferData}.
*/
public static final String javaSerializedObjectMimeType = "application/x-java-serialized-object";
/**
* To transfer a list of files to/from Java (and the underlying platform) a
* {@code DataFlavor} of this type/subtype and representation class of
* {@code java.util.List} is used. Each element of the list is
* required/guaranteed to be of type {@code java.io.File}.
*/
public static final DataFlavor javaFileListFlavor = createConstant("application/x-java-file-list;class=java.util.List", null);
/**
* To transfer a reference to an arbitrary Java object reference that has no
* associated MIME Content-type, across a {@code Transferable} interface
* WITHIN THE SAME JVM, a {@code DataFlavor} with this type/subtype is used,
* with a {@code representationClass} equal to the type of the
* class/interface being passed across the {@code Transferable}.
*
* The object reference returned from {@code Transferable.getTransferData}
* for a {@code DataFlavor} with this MIME Content-Type is required to be an
* instance of the representation Class of the {@code DataFlavor}.
*/
public static final String javaJVMLocalObjectMimeType = "application/x-java-jvm-local-objectref";
/**
* In order to pass a live link to a Remote object via a Drag and Drop
* {@code ACTION_LINK} operation a Mime Content Type of
* application/x-java-remote-object should be used, where the representation
* class of the {@code DataFlavor} represents the type of the {@code Remote}
* interface to be transferred.
*/
public static final String javaRemoteObjectMimeType = "application/x-java-remote-object";
/**
* Represents a piece of an HTML markup. The markup consists of the part
* selected on the source side. Therefore some tags in the markup may be
* unpaired. If the flavor is used to represent the data in a
* {@link Transferable} instance, no additional changes will be made. This
* DataFlavor instance represents the same HTML markup as DataFlavor
* instances which content MIME type does not contain document parameter
* and representation class is the String class.
*
* The returned {@code DataFlavor} will have the following characteristics:
*
* The returned {@code DataFlavor} will have the following characteristics:
*
* If the {@code mimeType} is
* "application/x-java-serialized-object; class=<representation class>",
* the result is the same as calling
* {@code new DataFlavor(Class.forName(
* Otherwise:
*
* The returned {@code DataFlavor} will have the following characteristics:
*
* If the mimeType is
* "application/x-java-serialized-object; class=<representation class>",
* the result is the same as calling
* {@code new DataFlavor(Class.forName(
* Otherwise:
*
* Flavors are first sorted by their MIME types in the following order:
*
* For example, "text/sgml" will be selected over "text/html", and
* {@code DataFlavor.stringFlavor} will be chosen over
* {@code DataFlavor.plainTextFlavor}.
*
* If two or more flavors share the best MIME type in the array, then that
* MIME type will be checked to see if it supports the charset parameter.
*
* The following MIME types support, or are treated as though they support,
* the charset parameter:
*
* If the best MIME type in the array does not support the charset
* parameter, the flavors which share that MIME type will then be sorted by
* their representation classes in the following order:
* {@code java.io.InputStream}, {@code java.nio.ByteBuffer}, {@code [B},
* <all others>.
*
* If two or more flavors share the best representation class, or if no
* flavor has one of the three specified representations, then one of those
* flavors will be chosen non-deterministically.
*
* If the best MIME type in the array does support the charset parameter,
* the flavors which share that MIME type will then be sorted by their
* representation classes in the following order: {@code java.io.Reader},
* {@code java.lang.String}, {@code java.nio.CharBuffer}, {@code [C},
* <all others>.
*
* If two or more flavors share the best representation class, and that
* representation is one of the four explicitly listed, then one of those
* flavors will be chosen non-deterministically. If, however, no flavor has
* one of the four specified representations, the flavors will then be
* sorted by their charsets. Unicode charsets, such as "UTF-16", "UTF-8",
* "UTF-16BE", "UTF-16LE", and their aliases, are considered best. After
* them, the platform default charset and its aliases are selected.
* "US-ASCII" and its aliases are worst. All other charsets are chosen in
* alphabetical order, but only charsets supported by this implementation of
* the Java platform will be considered.
*
* If two or more flavors share the best charset, the flavors will then
* again be sorted by their representation classes in the following order:
* {@code java.io.InputStream}, {@code java.nio.ByteBuffer}, {@code [B},
* <all others>.
*
* If two or more flavors share the best representation class, or if no
* flavor has one of the three specified representations, then one of those
* flavors will be chosen non-deterministically.
*
* @param availableFlavors an array of available {@code DataFlavor}s
* @return the best (highest fidelity) flavor according to the rules
* specified above, or {@code null}, if {@code availableFlavors} is
* {@code null}, has zero length, or contains no text flavors
* @since 1.3
*/
public static final DataFlavor selectBestTextFlavor(
DataFlavor[] availableFlavors) {
if (availableFlavors == null || availableFlavors.length == 0) {
return null;
}
DataFlavor bestFlavor = Collections.max(Arrays.asList(availableFlavors),
DataFlavorUtil.getTextFlavorComparator());
if (!bestFlavor.isFlavorTextType()) {
return null;
}
return bestFlavor;
}
/**
* Gets a Reader for a text flavor, decoded, if necessary, for the expected
* charset (encoding). The supported representation classes are
* {@code java.io.Reader}, {@code java.lang.String},
* {@code java.nio.CharBuffer}, {@code [C}, {@code java.io.InputStream},
* {@code java.nio.ByteBuffer}, and {@code [B}.
*
* Because text flavors which do not support the charset parameter are
* encoded in a non-standard format, this method should not be called for
* such flavors. However, in order to maintain backward-compatibility, if
* this method is called for such a flavor, this method will treat the
* flavor as though it supports the charset parameter and attempt to decode
* it accordingly. See {@code selectBestTextFlavor} for a list of text
* flavors which do not support the charset parameter.
*
* @param transferable the {@code Transferable} whose data will be
* requested in this flavor
* @return a {@code Reader} to read the {@code Transferable}'s data
* @throws IllegalArgumentException if the representation class is not one
* of the seven listed above
* @throws IllegalArgumentException if the {@code Transferable} has
* {@code null} data
* @throws NullPointerException if the {@code Transferable} is {@code null}
* @throws UnsupportedEncodingException if this flavor's representation is
* {@code java.io.InputStream}, {@code java.nio.ByteBuffer}, or
* {@code [B} and this flavor's encoding is not supported by this
* implementation of the Java platform
* @throws UnsupportedFlavorException if the {@code Transferable} does not
* support this flavor
* @throws IOException if the data cannot be read because of an I/O error
* @see #selectBestTextFlavor
* @since 1.3
*/
public Reader getReaderForText(Transferable transferable)
throws UnsupportedFlavorException, IOException
{
Object transferObject = transferable.getTransferData(this);
if (transferObject == null) {
throw new IllegalArgumentException
("getTransferData() returned null");
}
if (transferObject instanceof Reader) {
return (Reader)transferObject;
} else if (transferObject instanceof String) {
return new StringReader((String)transferObject);
} else if (transferObject instanceof CharBuffer) {
CharBuffer buffer = (CharBuffer)transferObject;
int size = buffer.remaining();
char[] chars = new char[size];
buffer.get(chars, 0, size);
return new CharArrayReader(chars);
} else if (transferObject instanceof char[]) {
return new CharArrayReader((char[])transferObject);
}
InputStream stream = null;
if (transferObject instanceof InputStream) {
stream = (InputStream)transferObject;
} else if (transferObject instanceof ByteBuffer) {
ByteBuffer buffer = (ByteBuffer)transferObject;
int size = buffer.remaining();
byte[] bytes = new byte[size];
buffer.get(bytes, 0, size);
stream = new ByteArrayInputStream(bytes);
} else if (transferObject instanceof byte[]) {
stream = new ByteArrayInputStream((byte[])transferObject);
}
if (stream == null) {
throw new IllegalArgumentException("transfer data is not Reader, String, CharBuffer, char array, InputStream, ByteBuffer, or byte array");
}
String encoding = getParameter("charset");
return (encoding == null)
? new InputStreamReader(stream)
: new InputStreamReader(stream, encoding);
}
/**
* Returns the MIME type string for this {@code DataFlavor}.
*
* @return the MIME type string for this flavor
*/
public String getMimeType() {
return (mimeType != null) ? mimeType.toString() : null;
}
/**
* Returns the {@code Class} which objects supporting this
* {@code DataFlavor} will return when this {@code DataFlavor} is requested.
*
* @return the {@code Class} which objects supporting this
* {@code DataFlavor} will return when this {@code DataFlavor} is
* requested
*/
public Class getRepresentationClass() {
return representationClass;
}
/**
* Returns the human presentable name for the data format that this
* {@code DataFlavor} represents. This name would be localized for different
* countries.
*
* @return the human presentable name for the data format that this
* {@code DataFlavor} represents
*/
public String getHumanPresentableName() {
return humanPresentableName;
}
/**
* Returns the primary MIME type for this {@code DataFlavor}.
*
* @return the primary MIME type of this {@code DataFlavor}
*/
public String getPrimaryType() {
return (mimeType != null) ? mimeType.getPrimaryType() : null;
}
/**
* Returns the sub MIME type of this {@code DataFlavor}.
*
* @return the Sub MIME type of this {@code DataFlavor}
*/
public String getSubType() {
return (mimeType != null) ? mimeType.getSubType() : null;
}
/**
* Returns the human presentable name for this {@code DataFlavor} if
* {@code paramName} equals "humanPresentableName". Otherwise returns the
* MIME type value associated with {@code paramName}.
*
* @param paramName the parameter name requested
* @return the value of the name parameter, or {@code null} if there is no
* associated value
*/
public String getParameter(String paramName) {
if (paramName.equals("humanPresentableName")) {
return humanPresentableName;
} else {
return (mimeType != null)
? mimeType.getParameter(paramName) : null;
}
}
/**
* Sets the human presentable name for the data format that this
* {@code DataFlavor} represents. This name would be localized for different
* countries.
*
* @param humanPresentableName the new human presentable name
*/
public void setHumanPresentableName(String humanPresentableName) {
this.humanPresentableName = humanPresentableName;
}
/**
* {@inheritDoc}
*
* The equals comparison for the {@code DataFlavor} class is implemented as
* follows: Two {@code DataFlavor}s are considered equal if and only if
* their MIME primary type and subtype and representation class are equal.
* Additionally, if the primary type is "text", the subtype denotes a text
* flavor which supports the charset parameter, and the representation class
* is not {@code java.io.Reader}, {@code java.lang.String},
* {@code java.nio.CharBuffer}, or {@code [C}, the {@code charset} parameter
* must also be equal. If a charset is not explicitly specified for one or
* both {@code DataFlavor}s, the platform default encoding is assumed. See
* {@code selectBestTextFlavor} for a list of text flavors which support the
* charset parameter.
*
* @param o the {@code Object} to compare with {@code this}
* @return {@code true} if {@code that} is equivalent to this
* {@code DataFlavor}; {@code false} otherwise
* @see #selectBestTextFlavor
*/
public boolean equals(Object o) {
return ((o instanceof DataFlavor) && equals((DataFlavor)o));
}
/**
* This method has the same behavior as {@link #equals(Object)}. The only
* difference being that it takes a {@code DataFlavor} instance as a
* parameter.
*
* @param that the {@code DataFlavor} to compare with {@code this}
* @return {@code true} if {@code that} is equivalent to this
* {@code DataFlavor}; {@code false} otherwise
* @see #selectBestTextFlavor
*/
public boolean equals(DataFlavor that) {
if (that == null) {
return false;
}
if (this == that) {
return true;
}
if (!Objects.equals(this.getRepresentationClass(), that.getRepresentationClass())) {
return false;
}
if (mimeType == null) {
if (that.mimeType != null) {
return false;
}
} else {
if (!mimeType.match(that.mimeType)) {
return false;
}
if ("text".equals(getPrimaryType())) {
if (DataFlavorUtil.doesSubtypeSupportCharset(this)
&& representationClass != null
&& !isStandardTextRepresentationClass()) {
String thisCharset =
DataFlavorUtil.canonicalName(this.getParameter("charset"));
String thatCharset =
DataFlavorUtil.canonicalName(that.getParameter("charset"));
if (!Objects.equals(thisCharset, thatCharset)) {
return false;
}
}
if ("html".equals(getSubType())) {
String thisDocument = this.getParameter("document");
String thatDocument = that.getParameter("document");
if (!Objects.equals(thisDocument, thatDocument)) {
return false;
}
}
}
}
return true;
}
/**
* Compares only the {@code mimeType} against the passed in {@code String}
* and {@code representationClass} is not considered in the comparison. If
* {@code representationClass} needs to be compared, then
* {@code equals(new DataFlavor(s))} may be used.
*
* @param s the {@code mimeType} to compare
* @return {@code true} if the String (MimeType) is equal; {@code false}
* otherwise or if {@code s} is {@code null}
* @deprecated As inconsistent with {@code hashCode()} contract, use
* {@link #isMimeTypeEqual(String)} instead.
*/
@Deprecated
public boolean equals(String s) {
if (s == null || mimeType == null)
return false;
return isMimeTypeEqual(s);
}
/**
* Returns hash code for this {@code DataFlavor}. For two equal
* {@code DataFlavor}s, hash codes are equal. For the {@code String} that
* matches {@code DataFlavor.equals(String)}, it is not guaranteed that
* {@code DataFlavor}'s hash code is equal to the hash code of the
* {@code String}.
*
* @return a hash code for this {@code DataFlavor}
*/
public int hashCode() {
int total = 0;
if (representationClass != null) {
total += representationClass.hashCode();
}
if (mimeType != null) {
String primaryType = mimeType.getPrimaryType();
if (primaryType != null) {
total += primaryType.hashCode();
}
// Do not add subType.hashCode() to the total. equals uses
// MimeType.match which reports a match if one or both of the
// subTypes is '*', regardless of the other subType.
if ("text".equals(primaryType)) {
if (DataFlavorUtil.doesSubtypeSupportCharset(this)
&& representationClass != null
&& !isStandardTextRepresentationClass()) {
String charset = DataFlavorUtil.canonicalName(getParameter("charset"));
if (charset != null) {
total += charset.hashCode();
}
}
if ("html".equals(getSubType())) {
String document = this.getParameter("document");
if (document != null) {
total += document.hashCode();
}
}
}
}
return total;
}
/**
* Identical to {@link #equals(DataFlavor)}.
*
* @param that the {@code DataFlavor} to compare with {@code this}
* @return {@code true} if {@code that} is equivalent to this
* {@code DataFlavor}; {@code false} otherwise
* @see #selectBestTextFlavor
* @since 1.3
*/
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}. Parameters are
* not included in the comparison.
*
* @param mimeType the string representation of the MIME type
* @return {@code 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}
*/
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} of two {@code DataFlavor} objects. No
* parameters are considered.
*
* @param dataFlavor the {@code DataFlavor} to be compared
* @return {@code true} if the {@code MimeType}s are equal, otherwise
* {@code false}
*/
public final boolean isMimeTypeEqual(DataFlavor dataFlavor) {
return isMimeTypeEqual(dataFlavor.mimeType);
}
/**
* Compares the {@code mimeType} of two {@code DataFlavor} objects. No
* parameters are considered.
*
* @return {@code true} if the {@code MimeType}s are equal, otherwise
* {@code false}
*/
private boolean isMimeTypeEqual(MimeType mtype) {
if (this.mimeType == null) {
return (mtype == null);
}
return mimeType.match(mtype);
}
/**
* Checks if the representation class is one of the standard text
* representation classes.
*
* @return {@code true} if the representation class is one of the standard
* text representation classes, otherwise {@code false}
*/
private boolean isStandardTextRepresentationClass() {
return isRepresentationClassReader()
|| String.class.equals(representationClass)
|| isRepresentationClassCharBuffer()
|| char[].class.equals(representationClass);
}
/**
* Does the {@code DataFlavor} represent a serialized object?
*
* @return whether or not a serialized object is represented
*/
public boolean isMimeTypeSerializedObject() {
return isMimeTypeEqual(javaSerializedObjectMimeType);
}
/**
* Returns the default representation class.
*
* @return the default representation class
*/
public final Class getDefaultRepresentationClass() {
return ioInputStreamClass;
}
/**
* Returns the name of the default representation class.
*
* @return the name of the default representation class
*/
public final String getDefaultRepresentationClassAsString() {
return getDefaultRepresentationClass().getName();
}
/**
* Does the {@code DataFlavor} represent a {@code java.io.InputStream}?
*
* @return whether or not this {@code DataFlavor} represent a
* {@code java.io.InputStream}
*/
public boolean isRepresentationClassInputStream() {
return ioInputStreamClass.isAssignableFrom(representationClass);
}
/**
* Returns whether the representation class for this {@code DataFlavor} is
* {@code java.io.Reader} or a subclass thereof.
*
* @return whether or not the representation class for this
* {@code DataFlavor} is {@code java.io.Reader} 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} is
* {@code java.nio.CharBuffer} or a subclass thereof.
*
* @return whether or not the representation class for this
* {@code DataFlavor} is {@code java.nio.CharBuffer} 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} is
* {@code java.nio.ByteBuffer} or a subclass thereof.
*
* @return whether or not the representation class for this
* {@code DataFlavor} is {@code java.nio.ByteBuffer} or a subclass
* thereof
* @since 1.4
*/
public boolean isRepresentationClassByteBuffer() {
return java.nio.ByteBuffer.class.isAssignableFrom(representationClass);
}
/**
* Returns {@code true} if the representation class can be serialized.
*
* @return {@code true} if the representation class can be serialized
*/
public boolean isRepresentationClassSerializable() {
return java.io.Serializable.class.isAssignableFrom(representationClass);
}
/**
* Returns {@code true} if the representation class is {@code Remote}.
*
* @return {@code true} if the representation class is {@code Remote}
*/
public boolean isRepresentationClassRemote() {
return DataFlavorUtil.RMI.isRemote(representationClass);
}
/**
* Returns {@code true} if the {@code DataFlavor} specified represents a
* serialized object.
*
* @return {@code true} if the {@code DataFlavor} specified represents a
* Serialized Object
*/
public boolean isFlavorSerializedObjectType() {
return isRepresentationClassSerializable() && isMimeTypeEqual(javaSerializedObjectMimeType);
}
/**
* Returns {@code true} if the {@code DataFlavor} specified represents a
* remote object.
*
* @return {@code true} if the {@code DataFlavor} specified represents a
* Remote Object
*/
public boolean isFlavorRemoteObjectType() {
return isRepresentationClassRemote()
&& isRepresentationClassSerializable()
&& isMimeTypeEqual(javaRemoteObjectMimeType);
}
/**
* Returns {@code true} if the {@code DataFlavor} specified represents a
* list of file objects.
*
* @return {@code true} if the {@code DataFlavor} specified represents a
* {@code java.util.List} of {@code java.io.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} is a valid text flavor for this
* implementation of the Java platform. Only flavors equivalent to
* {@code DataFlavor.stringFlavor} and {@code DataFlavor}s with a primary
* MIME type of "text" can be valid text flavors.
*
* If this flavor supports the charset parameter, it must be equivalent to
* {@code DataFlavor.stringFlavor}, or its representation must be
* {@code java.io.Reader}, {@code java.lang.String},
* {@code java.nio.CharBuffer}, {@code [C}, {@code java.io.InputStream},
* {@code java.nio.ByteBuffer}, or {@code [B}. If the representation is
* {@code java.io.InputStream}, {@code java.nio.ByteBuffer}, or {@code [B},
* then this flavor's {@code charset} 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.
*
* If this flavor does not support the charset parameter, its representation
* must be {@code java.io.InputStream}, {@code java.nio.ByteBuffer}, or
* {@code [B}.
*
* See {@code selectBestTextFlavor} for a list of text flavors which support
* the charset parameter.
*
* @return {@code true} if this {@code DataFlavor} is a valid text flavor as
* described above; {@code false} otherwise
* @see #selectBestTextFlavor
* @since 1.4
*/
public boolean isFlavorTextType() {
return (DataFlavorUtil.isFlavorCharsetTextType(this) ||
DataFlavorUtil.isFlavorNoncharsetTextType(this));
}
/**
* Serializes this {@code DataFlavor}.
*/
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} 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 (!ode.eof || ode.length != 0) {
throw ode;
}
// Ensure backward compatibility.
// Old versions didn't write the representation class to the stream.
if (rcn != null) {
representationClass =
DataFlavor.tryToLoadClass(rcn, getClass().getClassLoader());
}
}
}
/**
* Returns a clone of this {@code DataFlavor}.
*
* @return a clone of this {@code DataFlavor}
*/
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} for every MIME Type parameter to allow
* {@code DataFlavor} subclasses to handle special parameters like the
* text/plain {@code charset} parameters, whose values are case insensitive.
* (MIME type parameter values are supposed to be case sensitive.
*
* This method is called for each parameter name/value pair and should
* return the normalized representation of the {@code parameterValue}.
*
* @param parameterName the parameter name
* @param parameterValue the parameter value
* @return the parameter value
* @deprecated 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} 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.
*
* @param mimeType the mime type
* @return the mime type
* @deprecated 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
* representationClass = java.lang.String
* mimeType = "application/x-java-serialized-object"
*
*/
public static final DataFlavor stringFlavor = createConstant(java.lang.String.class, "Unicode String");
/**
* The {@code DataFlavor} representing a Java Image class, where:
*
* representationClass = java.awt.Image
* mimeType = "image/x-java-image"
*
* Will be {@code null} if {@code java.awt.Image} is not visible, the
* {@code java.desktop} module is not loaded, or the {@code java.desktop}
* module is not in the run-time image.
*/
public static final DataFlavor imageFlavor = createConstant("image/x-java-image; class=java.awt.Image", "Image");
/**
* The {@code DataFlavor} representing plain text with Unicode encoding,
* where:
*
* representationClass = InputStream
* mimeType = "text/plain; charset=unicode"
*
* This {@code DataFlavor} has been deprecated because:
*
*
*
* @deprecated as of 1.3. Use {@link #getReaderForText} instead of
* {@code Transferable.getTransferData(DataFlavor.plainTextFlavor)}.
*/
@Deprecated
public static final DataFlavor plainTextFlavor = createConstant("text/plain; charset=unicode; class=java.io.InputStream", "Plain Text");
/**
* A MIME Content-Type of application/x-java-serialized-object represents a
* graph of Java object(s) that have been made persistent.
*
* representationClass = String
* mimeType = "text/html"
*
*
* @since 1.8
*/
public static DataFlavor selectionHtmlFlavor = initHtmlDataFlavor("selection");
/**
* Represents a piece of an HTML markup. If possible, the markup received
* from a native system is supplemented with pair tags to be a well-formed
* HTML markup. If the flavor is used to represent the data in a
* {@link Transferable} instance, no additional changes will be made.
*
* representationClass = String
* mimeType = "text/html"
*
*
* @since 1.8
*/
public static DataFlavor fragmentHtmlFlavor = initHtmlDataFlavor("fragment");
/**
* Represents a piece of an HTML markup. If possible, the markup received
* from a native system is supplemented with additional tags to make up a
* well-formed HTML document. If the flavor is used to represent the data in
* a {@link Transferable} instance, no additional changes will be made.
*
* representationClass = String
* mimeType = "text/html"
*
*
* @since 1.8
*/
public static DataFlavor allHtmlFlavor = initHtmlDataFlavor("all");
/**
* Constructs a new {@code DataFlavor}. This constructor is provided only
* for the purpose of supporting the {@code Externalizable} interface. It is
* not intended for public (client) use.
*
* @since 1.2
*/
public DataFlavor() {
super();
}
/**
* Constructs a fully specified {@code DataFlavor}.
*
* @throws NullPointerException if either {@code primaryType},
* {@code subType} or {@code representationClass} is {@code null}
*/
private DataFlavor(String primaryType, String subType, MimeTypeParameterList params, Class representationClass, String humanPresentableName) {
super();
if (primaryType == null) {
throw new NullPointerException("primaryType");
}
if (subType == null) {
throw new NullPointerException("subType");
}
if (representationClass == null) {
throw new NullPointerException("representationClass");
}
if (params == null) params = new MimeTypeParameterList();
params.set("class", representationClass.getName());
if (humanPresentableName == null) {
humanPresentableName = params.get("humanPresentableName");
if (humanPresentableName == null)
humanPresentableName = primaryType + "/" + subType;
}
try {
mimeType = new MimeType(primaryType, subType, params);
} catch (MimeTypeParseException mtpe) {
throw new IllegalArgumentException("MimeType Parse Exception: " + mtpe.getMessage());
}
this.representationClass = representationClass;
this.humanPresentableName = humanPresentableName;
mimeType.removeParameter("humanPresentableName");
}
/**
* Constructs a {@code DataFlavor} that represents a Java class.
*
* representationClass = representationClass
* mimeType = application/x-java-serialized-object
*
*
* @param representationClass the class used to transfer data in this
* flavor
* @param humanPresentableName the human-readable string used to identify
* this flavor; if this parameter is {@code null} then the value of
* the MIME Content Type is used
* @throws NullPointerException if {@code representationClass} is
* {@code null}
*/
public DataFlavor(Class representationClass, String humanPresentableName) {
this("application", "x-java-serialized-object", null, representationClass, humanPresentableName);
if (representationClass == null) {
throw new NullPointerException("representationClass");
}
}
/**
* Constructs a {@code DataFlavor} that represents a {@code MimeType}.
*
* representationClass = InputStream
* mimeType = mimeType
*
*
* @param mimeType the string used to identify the MIME type for this
* flavor; if the {@code mimeType} does not specify a "class="
* parameter, or if the class is not successfully loaded, then an
* {@code IllegalArgumentException} is thrown
* @param humanPresentableName the human-readable string used to identify
* this flavor; if this parameter is {@code null} then the value of
* the MIME Content Type is used
* @throws IllegalArgumentException if {@code mimeType} is invalid or if the
* class is not successfully loaded
* @throws NullPointerException if {@code mimeType} is {@code null}
*/
public DataFlavor(String mimeType, String humanPresentableName) {
super();
if (mimeType == null) {
throw new NullPointerException("mimeType");
}
try {
initialize(mimeType, humanPresentableName, this.getClass().getClassLoader());
} catch (MimeTypeParseException mtpe) {
throw new IllegalArgumentException("failed to parse:" + mimeType);
} catch (ClassNotFoundException cnfe) {
throw new IllegalArgumentException("can't find specified class: " + cnfe.getMessage());
}
}
/**
* Constructs a {@code DataFlavor} that represents a {@code MimeType}.
*
* representationClass = InputStream
* mimeType = mimeType
*
*
* @param mimeType the string used to identify the MIME type for this
* flavor
* @param humanPresentableName the human-readable string used to identify
* this flavor
* @param classLoader the class loader to use
* @throws ClassNotFoundException if the class is not loaded
* @throws IllegalArgumentException if {@code mimeType} is invalid
* @throws NullPointerException if {@code mimeType} is {@code null}
*/
public DataFlavor(String mimeType, String humanPresentableName, ClassLoader classLoader) throws ClassNotFoundException {
super();
if (mimeType == null) {
throw new NullPointerException("mimeType");
}
try {
initialize(mimeType, humanPresentableName, classLoader);
} catch (MimeTypeParseException mtpe) {
throw new IllegalArgumentException("failed to parse:" + mimeType);
}
}
/**
* Constructs a {@code DataFlavor} from a {@code mimeType} string. The
* string can specify a "class=<fully specified Java class name>"
* parameter to create a {@code DataFlavor} with the desired representation
* class. If the string does not contain "class=" parameter,
* {@code java.io.InputStream} is used as default.
*
* @param mimeType the string used to identify the MIME type for this
* flavor; if the class specified by "class=" parameter is not
* successfully loaded, then a {@code ClassNotFoundException} is
* thrown
* @throws ClassNotFoundException if the class is not loaded
* @throws IllegalArgumentException if {@code mimeType} is invalid
* @throws NullPointerException if {@code mimeType} is {@code null}
*/
public DataFlavor(String mimeType) throws ClassNotFoundException {
super();
if (mimeType == null) {
throw new NullPointerException("mimeType");
}
try {
initialize(mimeType, null, this.getClass().getClassLoader());
} catch (MimeTypeParseException mtpe) {
throw new IllegalArgumentException("failed to parse:" + mimeType);
}
}
/**
* Common initialization code called from various constructors.
*
* @param mimeType the MIME Content Type (must have a class= param)
* @param humanPresentableName the human Presentable Name or {@code null}
* @param classLoader the fallback class loader to resolve against
* @throws MimeTypeParseException
* @throws ClassNotFoundException
* @throws NullPointerException if {@code mimeType} is {@code null}
* @see #tryToLoadClass
*/
private void initialize(String mimeType, String humanPresentableName, ClassLoader classLoader) throws MimeTypeParseException, ClassNotFoundException {
if (mimeType == null) {
throw new NullPointerException("mimeType");
}
this.mimeType = new MimeType(mimeType); // throws
String rcn = getParameter("class");
if (rcn == null) {
if ("application/x-java-serialized-object".equals(this.mimeType.getBaseType()))
throw new IllegalArgumentException("no representation class specified for:" + mimeType);
else
representationClass = java.io.InputStream.class; // default
} else { // got a class name
representationClass = DataFlavor.tryToLoadClass(rcn, classLoader);
}
this.mimeType.setParameter("class", representationClass.getName());
if (humanPresentableName == null) {
humanPresentableName = this.mimeType.getParameter("humanPresentableName");
if (humanPresentableName == null)
humanPresentableName = this.mimeType.getPrimaryType() + "/" + this.mimeType.getSubType();
}
this.humanPresentableName = humanPresentableName; // set it.
this.mimeType.removeParameter("humanPresentableName"); // just in case
}
/**
* String representation of this {@code DataFlavor} and its parameters. The
* resulting {@code String} contains the name of the {@code DataFlavor}
* class, this flavor's MIME type, and its representation class. If this
* flavor has a primary MIME type of "text", supports the charset parameter,
* and has an encoded representation, the flavor's charset is also included.
* See {@code selectBestTextFlavor} for a list of text flavors which support
* the charset parameter.
*
* @return string representation of this {@code DataFlavor}
* @see #selectBestTextFlavor
*/
public String toString() {
String string = getClass().getName();
string += "["+paramString()+"]";
return string;
}
private String paramString() {
String params = "";
params += "mimetype=";
if (mimeType == null) {
params += "null";
} else {
params += mimeType.getBaseType();
}
params += ";representationclass=";
if (representationClass == null) {
params += "null";
} else {
params += representationClass.getName();
}
if (DataFlavorUtil.isFlavorCharsetTextType(this) &&
(isRepresentationClassInputStream() ||
isRepresentationClassByteBuffer() ||
byte[].class.equals(representationClass)))
{
params += ";charset=" + DataFlavorUtil.getTextCharset(this);
}
return params;
}
/**
* Returns a {@code DataFlavor} representing plain text with Unicode
* encoding, where:
*
* representationClass = java.io.InputStream
* mimeType = "text/plain;
* charset=<platform default Unicode encoding>"
*
* @implNote Oracle's implementation for Microsoft Windows and macOS uses
* the encoding {@code utf-16le}. Oracle's implementation for Solaris and
* Linux uses the encoding {@code iso-10646-ucs-2}.
*
* @return a {@code DataFlavor} representing plain text with Unicode
* encoding
* @since 1.3
*/
public static final DataFlavor getTextPlainUnicodeFlavor() {
return new DataFlavor(
"text/plain;charset=" + DataFlavorUtil.getDesktopService().getDefaultUnicodeEncoding()
+";class=java.io.InputStream", "Plain Text");
}
/**
* Selects the best text {@code DataFlavor} from an array of
* {@code DataFlavor}s. Only {@code DataFlavor.stringFlavor}, and equivalent
* flavors, and flavors that have a primary MIME type of "text", are
* considered for selection.
*
*
*
*
* The following MIME types do not support, or are treated as though they do
* not support, the charset parameter:
*
*
* For "text/<other>" MIME types, the first time the JRE needs to
* determine whether the MIME type supports the charset parameter, it will
* check whether the parameter is explicitly listed in an arbitrarily chosen
* {@code DataFlavor} which uses that MIME type. If so, the JRE will assume
* from that point on that the MIME type supports the charset parameter and
* will not check again. If the parameter is not explicitly listed, the JRE
* will assume from that point on that the MIME type does not support the
* charset parameter and will not check again. Because this check is
* performed on an arbitrarily chosen {@code DataFlavor}, developers must
* ensure that all {@code DataFlavor}s with a "text/<other>" MIME type
* specify the charset parameter if it is supported by that MIME type.
* Developers should never rely on the JRE to substitute the platform's
* default charset for a "text/<other>" DataFlavor. Failure to adhere
* to this restriction will lead to undefined behavior.
*