javafx.scene.input.DataFormat Maven / Gradle / Ivy
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package javafx.scene.input;
import java.util.Arrays;
import java.util.Collections;
import java.util.HashSet;
import java.util.Iterator;
import java.util.Set;
import com.sun.javafx.util.WeakReferenceQueue;
import javafx.beans.NamedArg;
/**
* Data format identifier used as means
* of identifying the data stored on a clipboard/dragboard.
* @since JavaFX 2.0
*/
public class DataFormat {
/**
* A static cache of all DataFormats created and currently in use. This is needed
* by the underlying implementation, such that, given a mime type, we can determine
* the associated DataFormat. The OS level is going to supply us with a mime type
* (or other string based key), and we need to be able to map this back to the FX
* DataFormat.
*/
private static final WeakReferenceQueue DATA_FORMAT_LIST = new WeakReferenceQueue();
/**
* Represents a plain text string.
*/
public static final DataFormat PLAIN_TEXT = new DataFormat("text/plain");
/**
* Represents an HTML formatted string.
*/
public static final DataFormat HTML = new DataFormat("text/html");
/**
* Represents an RTF formatted string
*/
public static final DataFormat RTF = new DataFormat("text/rtf");
/**
* Represents a URL, encoded as a String
*/
public static final DataFormat URL = new DataFormat("text/uri-list");
/**
* A special platform specific image type, such as is commonly used
* on the clipboard and interoperates widely with other applications.
* For example, on Mac this might ultimately be a TIFF while on
* Windows it might be a DIB (device independent bitmap).
*/
public static final DataFormat IMAGE = new DataFormat("application/x-java-rawimage");
/**
* Represents a List of Files.
*/
public static final DataFormat FILES = new DataFormat("application/x-java-file-list", "java.file-list");
/**
* Data format used internally, represents dragged image. Making this
* a private field prevents user from creating this DataFormat and breaking
* our drag view implementation.
*/
private static final DataFormat DRAG_IMAGE = new DataFormat("application/x-java-drag-image");
/**
* Data format used internally, represents offset in the dragged image.
* Making this a private field prevents user from creating this DataFormat
* and breaking our drag view implementation.
*/
private static final DataFormat DRAG_IMAGE_OFFSET = new DataFormat("application/x-java-drag-image-offset");
/**
* A set of identifiers, typically mime types, for this DataFormat.
* In most cases this will be a single String.
*/
private final Set identifier;
/**
* Create a new DataFormat, specifying the set of ids that are associated with
* this data format. Typically the ids are one or more mime types. For each
* id, any data associated with this DataFormat will be registered on the
* clipboard. For example, suppose I had the following:
* {@code
* DataFormat fmt = new DataFormat("text/foo", "text/bar");
* Clipboard clipboard = Clipboard.getSystemClipboard();
* ClipboardContent content = new ClipboardContent();
* content.put(fmt, "Hello");
* clipboard.setContent(content);
* }
*
* With the above code, if I were to look on the clipboard, I'd find the String "Hello"
* listed both for "text/foo" and "text/bar" on the clipboard.
*
*
* Note that the ids may be subject to platform restrictions in some cases.
* For instance, Swing requires a mime type so if an {@code id} is not
* of the "type/subtype" format it won't be possible
* to drag data of this type from/to {@link javafx.embed.swing.JFXPanel}.
*
* @param ids The set of ids used to represent this DataFormat on the clipboard.
* @throws IllegalArgumentException if one of the given mime types is already
* assigned to another DataFormat.
*/
public DataFormat(@NamedArg("ids") String... ids) {
DATA_FORMAT_LIST.cleanup();
if (ids != null) {
for (String id : ids) {
if (lookupMimeType(id) != null) {
throw new IllegalArgumentException("DataFormat '" + id +
"' already exists.");
}
}
this.identifier = Collections.unmodifiableSet(new HashSet(Arrays.asList(ids)));
} else {
this.identifier = Collections.emptySet();
}
// Add to the statis data format list.
DATA_FORMAT_LIST.add(this);
}
/**
* Gets the unmodifiable set of identifiers for this DataFormat.
* @return an unmodifiable set that is never null.
*/
public final Set getIdentifiers() {
return identifier;
}
/**
* Returns a string representation of this {@code DataFormat} object.
* @return a string representation of this {@code DataFormat} object.
*/
@Override public String toString() {
if (identifier.isEmpty()) {
return "[]";
} else if (identifier.size() == 1) {
StringBuilder sb = new StringBuilder("[");
sb.append(identifier.iterator().next());
return (sb.append("]").toString());
} else {
StringBuilder b = new StringBuilder("[");
Iterator itr = identifier.iterator();
while (itr.hasNext()) {
b = b.append(itr.next());
if (itr.hasNext()) {
b = b.append(", ");
}
}
b = b.append("]");
return b.toString();
}
}
/**
* Returns a hash code for this {@code DataFormat} object.
* @return a hash code for this {@code DataFormat} object.
*/
@Override public int hashCode() {
int hash = 7;
for (String id : identifier) {
hash = 31 * hash + id.hashCode();
}
return hash;
}
/**
* Indicates whether some other object is "equal to" this one.
* @param obj the reference object with which to compare.
* @return {@code true} if this object is equal to the {@code obj} argument; {@code false} otherwise.
*/
@Override public boolean equals(Object obj) {
if (obj == null || ! (obj instanceof DataFormat)) {
return false;
}
DataFormat otherDataFormat = (DataFormat) obj;
if (identifier.equals(otherDataFormat.identifier)) {
return true;
}
return false;
}
/**
* Looks for the DataFormat which has been previously created with
* the given mime type as one of its ids.
* @param mimeType If null or the empty string, then null is returned.
* @return The matching DataFormat
*/
public static DataFormat lookupMimeType(String mimeType) {
if (mimeType == null || mimeType.length() == 0) {
return null;
}
Iterator itr = DATA_FORMAT_LIST.iterator();
while (itr.hasNext()) {
DataFormat dataFormat = (DataFormat) itr.next();
if (dataFormat.getIdentifiers().contains(mimeType)) {
return dataFormat;
}
}
return null;
}
}