StringSelection.java

/*
 * @(#)StringSelection.java	1.14 06/10/10
 *
 * Copyright  1990-2008 Sun Microsystems, Inc. All Rights Reserved.
 * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER
 * 
 * This program is free software; you can redistribute it and/or
 * modify it under the terms of the GNU General Public License version
 * 2 only, as published by the Free Software Foundation. 
 * 
 * This program is distributed in the hope that it will be useful, but
 * WITHOUT ANY WARRANTY; without even the implied warranty of
 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
 * General Public License version 2 for more details (a copy is
 * included at /legal/license.txt). 
 * 
 * You should have received a copy of the GNU General Public License
 * version 2 along with this work; if not, write to the Free Software
 * Foundation, Inc., 51 Franklin St, Fifth Floor, Boston, MA
 * 02110-1301 USA 
 * 
 * Please contact Sun Microsystems, Inc., 4150 Network Circle, Santa
 * Clara, CA 95054 or visit www.sun.com if you need additional
 * information or have any questions. 
 *
 */

package java.awt.datatransfer;

import java.io.*;

/**
 * A Transferable which implements the capability required to transfer a
 * String.
 *
 * This Transferable properly supports <code>DataFlavor.stringFlavor</code>
 * and all equivalent flavors. Support for <code>DataFlavor.plainTextFlavor
 * </code> and all equivalent flavors is <b>deprecated</b>. No other
 * DataFlavors are supported.
 *
 * @see java.awt.datatransfer.DataFlavor.stringFlavor
 * @see java.awt.datatransfer.DataFlavor.plainTextFlavor
 */
public class StringSelection implements Transferable, ClipboardOwner {
    private static final int STRING = 0;
    private static final int PLAIN_TEXT = 1;
    private static final DataFlavor[] flavors = {
            DataFlavor.stringFlavor,
            DataFlavor.plainTextFlavor // deprecated
        };
    private String data;
    /**
     * Creates a Transferable capable of transferring the specified String.
     */
    public StringSelection(String data) {
        this.data = data;
    }

    /**
     * Returns an array of flavors in which this Transferable can provide
     * the data. <code>DataFlavor.stringFlavor</code> is properly supported.
     * Support for <code>DataFlavor.plainTextFlavor</code> is
     * <b>deprecated</b>.
     *
     * @return an array of length two, whose elements are <code>DataFlavor.
     *         stringFlavor</code> and <code>DataFlavor.plainTextFlavor</code>.
     */
    public DataFlavor[] getTransferDataFlavors() {
        // returning flavors itself would allow client code to modify
        // our internal behavior
        return (DataFlavor[]) flavors.clone();
    }

    /**
     * Returns whether the requested flavor is supported by this Transferable.
     *
     * @param flavor the requested flavor for the data
     * @return true if <code>flavor</code> is equal to
     *   <code>DataFlavor.stringFlavor</code> or
     *   <code>DataFlavor.plainTextFlavor</code>; false if <code>flavor</code>
     *   is not one of the above flavors
     * @throws NullPointerException if flavor is <code>null</code>
     */
    public boolean isDataFlavorSupported(DataFlavor flavor) {
        // JCK Test StringSelection0003: if 'flavor' is null, throw NPE
        for (int i = 0; i < flavors.length; i++) {
            if (flavor.equals(flavors[i])) {
                return true;
            }
        }
        return false;
    }

    /**
     * Returns the Transferable's data in the requested DataFlavor if
     * possible. If the desired flavor is <code>DataFlavor.stringFlavor</code>,
     * or an equivalent flavor, the String representing the selection is
     * returned. If the desired flavor is </code>DataFlavor.plainTextFlavor
     * </code>, or an equivalent flavor, a Reader is returned. <b>Note:<b>
     * The behavior of this method for </code>DataFlavor.plainTextFlavor</code>
     * and equivalent DataFlavors is inconsistent with the definition of
     * <code>DataFlavor.plainTextFlavor</code>.
     *
     * @param flavor the requested flavor for the data
     * @return the data in the requested flavor, as outlined above.
     * @throws UnsupportedFlavorException if the requested data flavor is
     *         not equivalent to either <code>DataFlavor.stringFlavor</code>
     *         or <code>DataFlavor.plainTextFlavor</code>.
     * @throws IOException if an IOException occurs while retrieving the data.
     *         By default, StringSelection never throws this exception, but a
     *         subclass may.
     * @throws NullPointerException if flavor is <code>null</code>
     * @see java.io.Reader
     */
    public Object getTransferData(DataFlavor flavor)
        throws UnsupportedFlavorException, IOException {
        // JCK Test StringSelection0007: if 'flavor' is null, throw NPE
        if (flavor.equals(flavors[STRING])) {
            return (Object) data;
        } else if (flavor.equals(flavors[PLAIN_TEXT])) {
            return new StringReader(data);
        } else {
            throw new UnsupportedFlavorException(flavor);
        }
    }

    public void lostOwnership(Clipboard clipboard, Transferable contents) {}
}