jtextcomponent.java

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   *
   * @see #removeKeymap
   * @see #getKeymap()
   * @see #keymaps
   */
  public static Keymap addKeymap(String n, Keymap parent)
  {
    Keymap k = new DefaultKeymap(n);
    k.setResolveParent(parent);
    if (n != null)
      keymaps.put(n, k);
    return k;
  }

  /**
   * Get the current Keymap of this component.
   *
   * @return The component's current Keymap
   *
   * @see #setKeymap
   * @see #keymap
   */
  public Keymap getKeymap() 
  {
    return keymap;
  }

  /**
   * Set the current Keymap of this component, installing appropriate
   * {@link KeymapWrapper} and {@link KeymapActionMap} objects in the
   * {@link InputMap} and {@link ActionMap} parent chains, respectively,
   * and fire a property change event with name <code>"keymap"</code>.
   *
   * @see #getKeymap()
   * @see #keymap
   */
  public void setKeymap(Keymap k) 
  {

    // phase 1: replace the KeymapWrapper entry in the InputMap chain.
    // the goal here is to always maintain the following ordering:
    //
    //   [InputMap]? -> [KeymapWrapper]? -> [InputMapUIResource]*
    // 
    // that is to say, component-specific InputMaps need to remain children
    // of Keymaps, and Keymaps need to remain children of UI-installed
    // InputMaps (and the order of each group needs to be preserved, of
    // course).
    
    KeymapWrapper kw = (k == null ? null : new KeymapWrapper(k));
    InputMap childInputMap = getInputMap(JComponent.WHEN_FOCUSED);
    if (childInputMap == null)
      setInputMap(JComponent.WHEN_FOCUSED, kw);
    else
      {
        while (childInputMap.getParent() != null 
               && !(childInputMap.getParent() instanceof KeymapWrapper)
               && !(childInputMap.getParent() instanceof InputMapUIResource))
          childInputMap = childInputMap.getParent();

        // option 1: there is nobody to replace at the end of the chain
        if (childInputMap.getParent() == null)
          childInputMap.setParent(kw);
        
        // option 2: there is already a KeymapWrapper in the chain which
        // needs replacing (possibly with its own parents, possibly without)
        else if (childInputMap.getParent() instanceof KeymapWrapper)
          {
            if (kw == null)
              childInputMap.setParent(childInputMap.getParent().getParent());
            else
              {
                kw.setParent(childInputMap.getParent().getParent());
                childInputMap.setParent(kw);
              }
          }

        // option 3: there is an InputMapUIResource in the chain, which marks
        // the place where we need to stop and insert ourselves
        else if (childInputMap.getParent() instanceof InputMapUIResource)
          {
            if (kw != null)
              {
                kw.setParent(childInputMap.getParent());
                childInputMap.setParent(kw);
              }
          }
      }

    // phase 2: replace the KeymapActionMap entry in the ActionMap chain

    KeymapActionMap kam = (k == null ? null : new KeymapActionMap(k));
    ActionMap childActionMap = getActionMap();
    if (childActionMap == null)
      setActionMap(kam);
    else
      {
        while (childActionMap.getParent() != null 
               && !(childActionMap.getParent() instanceof KeymapActionMap)
               && !(childActionMap.getParent() instanceof ActionMapUIResource))
          childActionMap = childActionMap.getParent();

        // option 1: there is nobody to replace at the end of the chain
        if (childActionMap.getParent() == null)
          childActionMap.setParent(kam);
        
        // option 2: there is already a KeymapActionMap in the chain which
        // needs replacing (possibly with its own parents, possibly without)
        else if (childActionMap.getParent() instanceof KeymapActionMap)
          {
            if (kam == null)
              childActionMap.setParent(childActionMap.getParent().getParent());
            else
              {
                kam.setParent(childActionMap.getParent().getParent());
                childActionMap.setParent(kam);
              }
          }

        // option 3: there is an ActionMapUIResource in the chain, which marks
        // the place where we need to stop and insert ourselves
        else if (childActionMap.getParent() instanceof ActionMapUIResource)
          {
            if (kam != null)
              {
                kam.setParent(childActionMap.getParent());
                childActionMap.setParent(kam);
              }
          }
      }

    // phase 3: update the explicit keymap field

    Keymap old = keymap;
    keymap = k;
    firePropertyChange("keymap", old, k);
  }

  /**
   * Resolves a set of bindings against a set of actions and inserts the
   * results into a {@link Keymap}. Specifically, for each provided binding
   * <code>b</code>, if there exists a provided action <code>a</code> such
   * that <code>a.getValue(Action.NAME) == b.ActionName</code> then an
   * entry is added to the Keymap mapping <code>b</code> to
   * <code>a</code>.
   *
   * @param map The Keymap to add new mappings to
   * @param bindings The set of bindings to add to the Keymap
   * @param actions The set of actions to resolve binding names against
   *
   * @see Action#NAME
   * @see Action#getValue
   * @see KeyBinding#actionName
   */
  public static void loadKeymap(Keymap map, 
                                JTextComponent.KeyBinding[] bindings, 
                                Action[] actions)
  {
    Hashtable acts = new Hashtable(actions.length);
    for (int i = 0; i < actions.length; ++i)
      acts.put(actions[i].getValue(Action.NAME), actions[i]);
      for (int i = 0; i < bindings.length; ++i)
      if (acts.containsKey(bindings[i].actionName))
        map.addActionForKeyStroke(bindings[i].key, (Action) acts.get(bindings[i].actionName));
  }

  /**
   * Returns the set of available Actions this component's associated
   * editor can run.  Equivalent to calling
   * <code>getUI().getEditorKit().getActions()</code>. This set of Actions
   * is a reasonable value to provide as a parameter to {@link
   * #loadKeymap}, when resolving a set of {@link KeyBinding} objects
   * against this component.
   *
   * @return The set of available Actions on this component's {@link EditorKit}
   *
   * @see TextUI#getEditorKit
   * @see EditorKit#getActions()
   */
  public Action[] getActions()
  {
    return getUI().getEditorKit(this).getActions();
  }
    
  // These are package-private to avoid an accessor method.
  Document doc;
  Caret caret;
  boolean editable;
  
  private Highlighter highlighter;
  private Color caretColor;
  private Color disabledTextColor;
  private Color selectedTextColor;
  private Color selectionColor;
  private Insets margin;
  private boolean dragEnabled;

  /**
   * Creates a new <code>JTextComponent</code> instance.
   */
  public JTextComponent()
  {
    Keymap defkeymap = getKeymap(DEFAULT_KEYMAP);
    if (defkeymap == null)
      {
        defkeymap = addKeymap(DEFAULT_KEYMAP, null);
        defkeymap.setDefaultAction(new DefaultEditorKit.DefaultKeyTypedAction());
      }

    setFocusable(true);
    setEditable(true);
    enableEvents(AWTEvent.KEY_EVENT_MASK);
    setOpaque(true);
    updateUI();
  }

  public void setDocument(Document newDoc)
  {
    Document oldDoc = doc;
    doc = newDoc;
    firePropertyChange("document", oldDoc, newDoc);
    revalidate();
    repaint();
  }

  public Document getDocument()
  {
    return doc;
  }

  /**
   * Get the <code>AccessibleContext</code> of this object.
   *
   * @return an <code>AccessibleContext</code> object
   */
  public AccessibleContext getAccessibleContext()
  {
    return new AccessibleJTextComponent();
  }

  public void setMargin(Insets m)
  {
    margin = m;
  }

  public Insets getMargin()
  {
    return margin;
  }

  public void setText(String text)
  {
    try
      {
        if (doc instanceof AbstractDocument)
          ((AbstractDocument) doc).replace(0, doc.getLength(), text, null);
        else
          {
            doc.remove(0, doc.getLength());
            doc.insertString(0, text, null);
          }
      }
    catch (BadLocationException e)
      {
        // This can never happen.
      }
  }

  /**
   * Retrieves the current text in this text document.
   *
   * @return the text
   *
   * @exception NullPointerException if the underlaying document is null
   */
  public String getText()
  {
    if (doc == null)
      return null;

    try
      {
        return doc.getText(0, doc.getLength());
      }
    catch (BadLocationException e)
      {
        // This should never happen.
        return "";
      }
  }

  /**
   * Retrieves a part of the current text in this document.
   *
   * @param offset the postion of the first character
   * @param length the length of the text to retrieve
   *
   * @return the text
   *
   * @exception BadLocationException if arguments do not hold pre-conditions
   */
  public String getText(int offset, int length)
    throws BadLocationException
  {
    return getDocument().getText(offset, length);
  }

  /**
   * Retrieves the currently selected text in this text document.
   *
   * @return the selected text
   *
   * @exception NullPointerException if the underlaying document is null
   */
  public String getSelectedText()
  {
    int start = getSelectionStart();
    int offset = getSelectionEnd() - start;
    
    if (offset <= 0)
      return null;
    
    try
      {
        return doc.getText(start, offset);
      }
    catch (BadLocationException e)
      {
        // This should never happen.
        return null;
      }
  }

  /**
   * Returns a string that specifies the name of the Look and Feel class
   * that renders this component.
   *
   * @return the string "TextComponentUI"
   */
  public String getUIClassID()
  {
    return "TextComponentUI";
  }

  /**
   * Returns a string representation of this JTextComponent.
   */
  protected String paramString()
  {
    // TODO: Do something useful here.
    return super.paramString();
  }

  /**
   * This method returns the label's UI delegate.
   *
   * @return The label's UI delegate.
   */
  public TextUI getUI()
  {
    return (TextUI) ui;
  }

  /**
   * This method sets the label's UI delegate.
   *
   * @param newUI The label's UI delegate.
   */
  public void setUI(TextUI newUI)
  {
    super.setUI(newUI);
  }

  /**
   * This method resets the label's UI delegate to the default UI for the
   * current look and feel.
   */
  public void updateUI()
  {
    setUI((TextUI) UIManager.getUI(this));
  }

  public Dimension getPreferredScrollableViewportSize()
  {
    return getPreferredSize();
  }

  public int getScrollableUnitIncrement(Rectangle visible, int orientation,
                                        int direction)
  {
    // We return 1/10 of the visible area as documented in Sun's API docs.
    if (orientation == SwingConstants.HORIZONTAL)
      return visible.width / 10;
    else if (orientation == SwingConstants.VERTICAL)
      return visible.height / 10;
    else
      throw new IllegalArgumentException("orientation must be either "
                                      + "javax.swing.SwingConstants.VERTICAL "
                                      + "or "
                                      + "javax.swing.SwingConstants.HORIZONTAL"
                                         );
  }

  public int getScrollableBlockIncrement(Rectangle visible, int orientation,
                                         int direction)
  {
    // We return the whole visible area as documented in Sun's API docs.
    if (orientation == SwingConstants.HORIZONTAL)
      return visible.width;
    else if (orientation == SwingConstants.VERTICAL)
      return visible.height;
    else
      throw new IllegalArgumentException("orientation must be either "
                                      + "javax.swing.SwingConstants.VERTICAL "
                                      + "or "
                                      + "javax.swing.SwingConstants.HORIZONTAL"
                                         );
  }

  /**
   * Checks whether this text component it editable.
   *
   * @return true if editable, false otherwise
   */
  public boolean isEditable()
  {
    return editable;
  }

  /**
   * Enables/disabled this text component's editability.
   *
   * @param newValue true to make it editable, false otherwise.
   */
  public void setEditable(boolean newValue)
  {
    if (editable == newValue)
      return;

    boolean oldValue = editable;
    editable = newValue;
    firePropertyChange("editable", oldValue, newValue);
  }

  /**
   * The <code>Caret</code> object used in this text component.
   *
   * @return the caret object
   */
  public Caret getCaret()
  {
    return caret;
  }

  /**
   * Sets a new <code>Caret</code> for this text component.
   *
   * @param newCaret the new <code>Caret</code> to set
   */
  public void setCaret(Caret newCaret)
  {
    if (caret != null)
      caret.deinstall(this);