src/jexer/bits/Clipboard.java

   1 /*
   2  * Jexer - Java Text User Interface
   3  *
   4  * The MIT License (MIT)
   5  *
   6  * Copyright (C) 2019 Kevin Lamonte
   7  *
   8  * Permission is hereby granted, free of charge, to any person obtaining a
   9  * copy of this software and associated documentation files (the "Software"),
  10  * to deal in the Software without restriction, including without limitation
  11  * the rights to use, copy, modify, merge, publish, distribute, sublicense,
  12  * and/or sell copies of the Software, and to permit persons to whom the
  13  * Software is furnished to do so, subject to the following conditions:
  14  *
  15  * The above copyright notice and this permission notice shall be included in
  16  * all copies or substantial portions of the Software.
  17  *
  18  * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
  19  * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
  20  * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL
  21  * THE AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
  22  * LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING
  23  * FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER
  24  * DEALINGS IN THE SOFTWARE.
  25  *
  26  * @author Kevin Lamonte [kevin.lamonte@gmail.com]
  27  * @version 1
  28  */
  29 package jexer.bits;
  30
  31 import java.awt.Image;
  32 import java.awt.Toolkit;
  33 import java.awt.datatransfer.DataFlavor;
  34 import java.awt.datatransfer.StringSelection;
  35 import java.awt.datatransfer.Transferable;
  36 import java.awt.datatransfer.UnsupportedFlavorException;
  37 import java.awt.image.BufferedImage;
  38 import java.io.IOException;
  39
  40 /**
  41  * Clipboard provides convenience methods to copy text and images to and from
  42  * a shared clipboard.  When the system clipboard is available it is used.
  43  */
  44 public class Clipboard {
  45
  46     // ------------------------------------------------------------------------
  47     // Variables --------------------------------------------------------------
  48     // ------------------------------------------------------------------------
  49
  50     /**
  51      * The image last copied to the clipboard.
  52      */
  53     private BufferedImage image = null;
  54
  55     /**
  56      * The text string last copied to the clipboard.
  57      */
  58     private String text = null;
  59
  60     /**
  61      * The system clipboard, or null if it is not available.
  62      */
  63     private java.awt.datatransfer.Clipboard systemClipboard = null;
  64
  65     // ------------------------------------------------------------------------
  66     // Constructors -----------------------------------------------------------
  67     // ------------------------------------------------------------------------
  68
  69     /**
  70      * Public constructor.
  71      */
  72     public Clipboard() {
  73         try {
  74             systemClipboard = Toolkit.getDefaultToolkit().getSystemClipboard();
  75         } catch (java.awt.HeadlessException e) {
  76             // SQUASH
  77         }
  78     }
  79
  80     // ------------------------------------------------------------------------
  81     // Clipboard --------------------------------------------------------------
  82     // ------------------------------------------------------------------------
  83
  84     /**
  85      * Copy an image to the clipboard.
  86      *
  87      * @param image image to copy
  88      */
  89     public void copyImage(final BufferedImage image) {
  90         this.image = image;
  91         if (systemClipboard != null) {
  92             // TODO
  93         }
  94     }
  95
  96     /**
  97      * Copy a text string to the clipboard.
  98      *
  99      * @param text string to copy
 100      */
 101     public void copyText(final String text) {
 102         this.text = text;
 103         if (systemClipboard != null) {
 104             StringSelection stringSelection = new StringSelection(text);
 105             systemClipboard.setContents(stringSelection, null);
 106         }
 107     }
 108
 109     /**
 110      * Obtain an image from the clipboard.
 111      *
 112      * @return image from the clipboard, or null if no image is available
 113      */
 114     public BufferedImage pasteImage() {
 115         if (systemClipboard != null) {
 116             getClipboardImage();
 117         }
 118         return image;
 119     }
 120
 121     /**
 122      * Obtain a text string from the clipboard.
 123      *
 124      * @return text string from the clipboard, or null if no text is
 125      * available
 126      */
 127     public String pasteText() {
 128         if (systemClipboard != null) {
 129             getClipboardText();
 130         }
 131         return text;
 132     }
 133
 134     /**
 135      * Returns true if the clipboard has an image.
 136      *
 137      * @return true if an image is available from the clipboard
 138      */
 139     public boolean isImage() {
 140         if (image == null) {
 141             getClipboardImage();
 142         }
 143         return (image != null);
 144     }
 145
 146     /**
 147      * Returns true if the clipboard has a text string.
 148      *
 149      * @return true if a text string is available from the clipboard
 150      */
 151     public boolean isText() {
 152         if (text == null) {
 153             getClipboardText();
 154         }
 155         return (text != null);
 156     }
 157
 158     /**
 159      * Returns true if the clipboard is empty.
 160      *
 161      * @return true if the clipboard is empty
 162      */
 163     public boolean isEmpty() {
 164         return ((isText() == false) && (isImage() == false));
 165     }
 166
 167     /**
 168      * Copy image from the clipboard to text.
 169      */
 170     private void getClipboardImage() {
 171         if (systemClipboard != null) {
 172             Transferable contents = systemClipboard.getContents(null);
 173             if (contents != null) {
 174                 if (contents.isDataFlavorSupported(DataFlavor.imageFlavor)) {
 175                     try {
 176                         Image img = (Image) contents.getTransferData(DataFlavor.imageFlavor);
 177                         image = new BufferedImage(img.getWidth(null),
 178                             img.getHeight(null), BufferedImage.TYPE_INT_ARGB);
 179                         image.getGraphics().drawImage(img, 0, 0, null);
 180                     } catch (IOException e) {
 181                         // SQUASH
 182                     } catch (UnsupportedFlavorException e) {
 183                         // SQUASH
 184                     }
 185                 }
 186             }
 187         }
 188     }
 189
 190     /**
 191      * Copy text string from the clipboard to text.
 192      */
 193     private void getClipboardText() {
 194         if (systemClipboard != null) {
 195             Transferable contents = systemClipboard.getContents(null);
 196             if (contents != null) {
 197                 if (contents.isDataFlavorSupported(DataFlavor.stringFlavor)) {
 198                     try {
 199                         text = (String) contents.getTransferData(DataFlavor.stringFlavor);
 200                     } catch (IOException e) {
 201                         // SQUASH
 202                     } catch (UnsupportedFlavorException e) {
 203                         // SQUASH
 204                     }
 205                 }
 206             }
 207         }
 208     }
 209
 210     /**
 211      * Clear whatever is on the local clipboard.  Note that this will not
 212      * clear the system clipboard.
 213      */
 214     public void clear() {
 215         image = null;
 216         text = null;
 217     }
 218
 219 }