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 * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
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 * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
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package javax.swing.text;

import java.util.Vector;
import java.awt.*;
import javax.swing.event.*;
import javax.swing.SwingConstants;


CompositeView is an abstract View
implementation which manages one or more child views.
(Note that CompositeView is intended
for managing relatively small numbers of child views.)
CompositeView is intended to be used as
a starting point for View implementations,
such as BoxView, that will contain child
Views. Subclasses that wish to manage the
collection of child Views should use the replace method. As View invokes
replace during DocumentListener
notification, you normally won't need to directly
invoke replace.

While CompositeView
does not impose a layout policy on its child Views,
it does allow for inseting the child Views it will contain. The insets can be set by either setInsets or setParagraphInsets. 
In addition to the abstract methods of View, subclasses of CompositeView will need to
override:

    

  • isBefore - Used to test if a given View location is before the visual space
    of the CompositeView.

  • isAfter - Used to test if a given View location is after the visual space
    of the CompositeView.

  • getViewAtPoint - Returns the view at a given visual location. 
  • childAllocation - Returns the bounds of a particular child View.
    getChildAllocation will invoke
    childAllocation after offseting
    the bounds by the Insets of the
    CompositeView.



Author: Timothy Prinzing
/**
 * <code>CompositeView</code> is an abstract <code>View</code>
 * implementation which manages one or more child views.
 * (Note that <code>CompositeView</code> is intended
 * for managing relatively small numbers of child views.)
 * <code>CompositeView</code> is intended to be used as
 * a starting point for <code>View</code> implementations,
 * such as <code>BoxView</code>, that will contain child
 * <code>View</code>s. Subclasses that wish to manage the
 * collection of child <code>View</code>s should use the
 * {@link #replace} method.  As <code>View</code> invokes
 * <code>replace</code> during <code>DocumentListener</code>
 * notification, you normally won't need to directly
 * invoke <code>replace</code>.
 *
 * <p>While <code>CompositeView</code>
 * does not impose a layout policy on its child <code>View</code>s,
 * it does allow for inseting the child <code>View</code>s
 * it will contain.  The insets can be set by either
 * {@link #setInsets} or {@link #setParagraphInsets}.
 *
 * <p>In addition to the abstract methods of
 * {@link javax.swing.text.View},
 * subclasses of <code>CompositeView</code> will need to
 * override:
 * <ul>
 * <li>{@link #isBefore} - Used to test if a given
 *     <code>View</code> location is before the visual space
 *     of the <code>CompositeView</code>.
 * <li>{@link #isAfter} - Used to test if a given
 *     <code>View</code> location is after the visual space
 *     of the <code>CompositeView</code>.
 * <li>{@link #getViewAtPoint} - Returns the view at
 *     a given visual location.
 * <li>{@link #childAllocation} - Returns the bounds of
 *     a particular child <code>View</code>.
 *     <code>getChildAllocation</code> will invoke
 *     <code>childAllocation</code> after offseting
 *     the bounds by the <code>Inset</code>s of the
 *     <code>CompositeView</code>.
 * </ul>
 *
 * @author  Timothy Prinzing
 */
public abstract class CompositeView extends View {

    
Constructs a CompositeView for the given element.

Params:
  • elem –  the element this view is responsible for
/**
     * Constructs a <code>CompositeView</code> for the given element.
     *
     * @param elem  the element this view is responsible for
     */
    public CompositeView(Element elem) {
        super(elem);
        children = new View[1];
        nchildren = 0;
        childAlloc = new Rectangle();
    }

    
Loads all of the children to initialize the view. This is called by the setParent method. Subclasses can reimplement this to initialize their child views in a different manner. The default implementation creates a child view for each child element. 
Params:
  • f – the view factory
See Also:
/**
     * Loads all of the children to initialize the view.
     * This is called by the {@link #setParent}
     * method.  Subclasses can reimplement this to initialize
     * their child views in a different manner.  The default
     * implementation creates a child view for each
     * child element.
     *
     * @param f the view factory
     * @see #setParent
     */
    protected void loadChildren(ViewFactory f) {
        if (f == null) {
            // No factory. This most likely indicates the parent view
            // has changed out from under us, bail!
            return;
        }
        Element e = getElement();
        int n = e.getElementCount();
        if (n > 0) {
            View[] added = new View[n];
            for (int i = 0; i < n; i++) {
                added[i] = f.create(e.getElement(i));
            }
            replace(0, 0, added);
        }
    }

    // --- View methods ---------------------------------------------

    
Sets the parent of the view.
This is reimplemented to provide the superclass
behavior as well as calling the loadChildren
method if this view does not already have children.
The children should not be loaded in the
constructor because the act of setting the parent
may cause them to try to search up the hierarchy
(to get the hosting Container for example).
If this view has children (the view is being moved
from one place in the view hierarchy to another),
the loadChildren method will not be called.

Params:
  • parent – the parent of the view, null if none
/**
     * Sets the parent of the view.
     * This is reimplemented to provide the superclass
     * behavior as well as calling the <code>loadChildren</code>
     * method if this view does not already have children.
     * The children should not be loaded in the
     * constructor because the act of setting the parent
     * may cause them to try to search up the hierarchy
     * (to get the hosting <code>Container</code> for example).
     * If this view has children (the view is being moved
     * from one place in the view hierarchy to another),
     * the <code>loadChildren</code> method will not be called.
     *
     * @param parent the parent of the view, <code>null</code> if none
     */
    public void setParent(View parent) {
        super.setParent(parent);
        if ((parent != null) && (nchildren == 0)) {
            ViewFactory f = getViewFactory();
            loadChildren(f);
        }
    }

    
Returns the number of child views of this view.

See Also:
Returns:the number of views >= 0
/**
     * Returns the number of child views of this view.
     *
     * @return the number of views &gt;= 0
     * @see #getView
     */
    public int getViewCount() {
        return nchildren;
    }

    
Returns the n-th view in this container.

Params:
  • n – the number of the desired view, >= 0 && < getViewCount()
Returns:the view at index n
/**
     * Returns the n-th view in this container.
     *
     * @param n the number of the desired view, &gt;= 0 &amp;&amp; &lt; getViewCount()
     * @return the view at index <code>n</code>
     */
    public View getView(int n) {
        return children[n];
    }

    
Replaces child views.  If there are no views to remove
this acts as an insert.  If there are no views to
add this acts as a remove.  Views being removed will
have the parent set to null,
and the internal reference to them removed so that they
may be garbage collected.

Params:
  • offset – the starting index into the child views to insert
  the new views; >= 0 and <= getViewCount
  • length – the number of existing child views to remove;
  this should be a value >= 0 and <= (getViewCount() - offset)
  • views – the child views to add; this value can be
 null
  to indicate no children are being added (useful to remove)
/**
     * Replaces child views.  If there are no views to remove
     * this acts as an insert.  If there are no views to
     * add this acts as a remove.  Views being removed will
     * have the parent set to <code>null</code>,
     * and the internal reference to them removed so that they
     * may be garbage collected.
     *
     * @param offset the starting index into the child views to insert
     *   the new views; &gt;= 0 and &lt;= getViewCount
     * @param length the number of existing child views to remove;
     *   this should be a value &gt;= 0 and &lt;= (getViewCount() - offset)
     * @param views the child views to add; this value can be
     *  <code>null</code>
     *   to indicate no children are being added (useful to remove)
     */
    public void replace(int offset, int length, View[] views) {
        // make sure an array exists
        if (views == null) {
            views = ZERO;
        }

        // update parent reference on removed views
        for (int i = offset; i < offset + length; i++) {
            if (children[i].getParent() == this) {
                // in FlowView.java view might be referenced
                // from two super-views as a child. see logicalView
                children[i].setParent(null);
            }
            children[i] = null;
        }

        // update the array
        int delta = views.length - length;
        int src = offset + length;
        int nmove = nchildren - src;
        int dest = src + delta;
        if ((nchildren + delta) >= children.length) {
            // need to grow the array
            int newLength = Math.max(2*children.length, nchildren + delta);
            View[] newChildren = new View[newLength];
            System.arraycopy(children, 0, newChildren, 0, offset);
            System.arraycopy(views, 0, newChildren, offset, views.length);
            System.arraycopy(children, src, newChildren, dest, nmove);
            children = newChildren;
        } else {
            // patch the existing array
            System.arraycopy(children, src, children, dest, nmove);
            System.arraycopy(views, 0, children, offset, views.length);
        }
        nchildren = nchildren + delta;

        // update parent reference on added views
        for (int i = 0; i < views.length; i++) {
            views[i].setParent(this);
        }
    }

    
Fetches the allocation for the given child view to
render into. This enables finding out where various views
are located.

Params:
  • index – the index of the child, >= 0 && < getViewCount()
  • a –  the allocation to this view
Returns:the allocation to the child
/**
     * Fetches the allocation for the given child view to
     * render into. This enables finding out where various views
     * are located.
     *
     * @param index the index of the child, &gt;= 0 &amp;&amp; &lt; getViewCount()
     * @param a  the allocation to this view
     * @return the allocation to the child
     */
    public Shape getChildAllocation(int index, Shape a) {
        Rectangle alloc = getInsideAllocation(a);
        childAllocation(index, alloc);
        return alloc;
    }

    
Provides a mapping from the document model coordinate space
to the coordinate space of the view mapped to it.

Params:
  • pos – the position to convert >= 0
  • a – the allocated region to render into
  • b – a bias value of either Position.Bias.Forward
 or Position.Bias.Backward
Throws:
  • BadLocationException –  if the given position does
  not represent a valid location in the associated document
See Also:
Returns:the bounding box of the given position
/**
     * Provides a mapping from the document model coordinate space
     * to the coordinate space of the view mapped to it.
     *
     * @param pos the position to convert &gt;= 0
     * @param a the allocated region to render into
     * @param b a bias value of either <code>Position.Bias.Forward</code>
     *  or <code>Position.Bias.Backward</code>
     * @return the bounding box of the given position
     * @exception BadLocationException  if the given position does
     *   not represent a valid location in the associated document
     * @see View#modelToView
     */
    public Shape modelToView(int pos, Shape a, Position.Bias b) throws BadLocationException {
        boolean isBackward = (b == Position.Bias.Backward);
        int testPos = (isBackward) ? Math.max(0, pos - 1) : pos;
        if(isBackward && testPos < getStartOffset()) {
            return null;
        }
        int vIndex = getViewIndexAtPosition(testPos);
        if ((vIndex != -1) && (vIndex < getViewCount())) {
            View v = getView(vIndex);
            if(v != null && testPos >= v.getStartOffset() &&
               testPos < v.getEndOffset()) {
                Shape childShape = getChildAllocation(vIndex, a);
                if (childShape == null) {
                    // We are likely invalid, fail.
                    return null;
                }
                Shape retShape = v.modelToView(pos, childShape, b);
                if(retShape == null && v.getEndOffset() == pos) {
                    if(++vIndex < getViewCount()) {
                        v = getView(vIndex);
                        retShape = v.modelToView(pos, getChildAllocation(vIndex, a), b);
                    }
                }
                return retShape;
            }
        }
        throw new BadLocationException("Position not represented by view",
                                       pos);
    }

    
Provides a mapping from the document model coordinate space
to the coordinate space of the view mapped to it.

Params:
  • p0 – the position to convert >= 0
  • b0 – the bias toward the previous character or the
 next character represented by p0, in case the
 position is a boundary of two views; either
 Position.Bias.Forward or
 Position.Bias.Backward
  • p1 – the position to convert >= 0
  • b1 – the bias toward the previous character or the
 next character represented by p1, in case the
 position is a boundary of two views
  • a – the allocated region to render into
Throws:
See Also:
Returns:the bounding box of the given position is returned
/**
     * Provides a mapping from the document model coordinate space
     * to the coordinate space of the view mapped to it.
     *
     * @param p0 the position to convert &gt;= 0
     * @param b0 the bias toward the previous character or the
     *  next character represented by p0, in case the
     *  position is a boundary of two views; either
     *  <code>Position.Bias.Forward</code> or
     *  <code>Position.Bias.Backward</code>
     * @param p1 the position to convert &gt;= 0
     * @param b1 the bias toward the previous character or the
     *  next character represented by p1, in case the
     *  position is a boundary of two views
     * @param a the allocated region to render into
     * @return the bounding box of the given position is returned
     * @exception BadLocationException  if the given position does
     *   not represent a valid location in the associated document
     * @exception IllegalArgumentException for an invalid bias argument
     * @see View#viewToModel
     */
    public Shape modelToView(int p0, Position.Bias b0, int p1, Position.Bias b1, Shape a) throws BadLocationException {
        if (p0 == getStartOffset() && p1 == getEndOffset()) {
            return a;
        }
        Rectangle alloc = getInsideAllocation(a);
        Rectangle r0 = new Rectangle(alloc);
        View v0 = getViewAtPosition((b0 == Position.Bias.Backward) ?
                                    Math.max(0, p0 - 1) : p0, r0);
        Rectangle r1 = new Rectangle(alloc);
        View v1 = getViewAtPosition((b1 == Position.Bias.Backward) ?
                                    Math.max(0, p1 - 1) : p1, r1);
        if (v0 == v1) {
            if (v0 == null) {
                return a;
            }
            // Range contained in one view
            return v0.modelToView(p0, b0, p1, b1, r0);
        }
        // Straddles some views.
        int viewCount = getViewCount();
        int counter = 0;
        while (counter < viewCount) {
            View v;
            // Views may not be in same order as model.
            // v0 or v1 may be null if there is a gap in the range this
            // view contains.
            if ((v = getView(counter)) == v0 || v == v1) {
                View endView;
                Rectangle retRect;
                Rectangle tempRect = new Rectangle();
                if (v == v0) {
                    retRect = v0.modelToView(p0, b0, v0.getEndOffset(),
                                             Position.Bias.Backward, r0).
                              getBounds();
                    endView = v1;
                }
                else {
                    retRect = v1.modelToView(v1.getStartOffset(),
                                             Position.Bias.Forward,
                                             p1, b1, r1).getBounds();
                    endView = v0;
                }

                // Views entirely covered by range.
                while (++counter < viewCount &&
                       (v = getView(counter)) != endView) {
                    tempRect.setBounds(alloc);
                    childAllocation(counter, tempRect);
                    retRect.add(tempRect);
                }

                // End view.
                if (endView != null) {
                    Shape endShape;
                    if (endView == v1) {
                        endShape = v1.modelToView(v1.getStartOffset(),
                                                  Position.Bias.Forward,
                                                  p1, b1, r1);
                    }
                    else {
                        endShape = v0.modelToView(p0, b0, v0.getEndOffset(),
                                                  Position.Bias.Backward, r0);
                    }
                    if (endShape instanceof Rectangle) {
                        retRect.add((Rectangle)endShape);
                    }
                    else {
                        retRect.add(endShape.getBounds());
                    }
                }
                return retRect;
            }
            counter++;
        }
        throw new BadLocationException("Position not represented by view", p0);
    }

    
Provides a mapping from the view coordinate space to the logical
coordinate space of the model.

Params:
  • x –   x coordinate of the view location to convert >= 0
  • y –   y coordinate of the view location to convert >= 0
  • a – the allocated region to render into
  • bias – either Position.Bias.Forward or
 Position.Bias.Backward
See Also:
Returns:the location within the model that best represents the
 given point in the view >= 0
/**
     * Provides a mapping from the view coordinate space to the logical
     * coordinate space of the model.
     *
     * @param x   x coordinate of the view location to convert &gt;= 0
     * @param y   y coordinate of the view location to convert &gt;= 0
     * @param a the allocated region to render into
     * @param bias either <code>Position.Bias.Forward</code> or
     *  <code>Position.Bias.Backward</code>
     * @return the location within the model that best represents the
     *  given point in the view &gt;= 0
     * @see View#viewToModel
     */
    public int viewToModel(float x, float y, Shape a, Position.Bias[] bias) {
        Rectangle alloc = getInsideAllocation(a);
        if (isBefore((int) x, (int) y, alloc)) {
            // point is before the range represented
            int retValue = -1;

            try {
                retValue = getNextVisualPositionFrom(-1, Position.Bias.Forward,
                                                     a, EAST, bias);
            } catch (BadLocationException ble) { }
            catch (IllegalArgumentException iae) { }
            if(retValue == -1) {
                retValue = getStartOffset();
                bias[0] = Position.Bias.Forward;
            }
            return retValue;
        } else if (isAfter((int) x, (int) y, alloc)) {
            // point is after the range represented.
            int retValue = -1;
            try {
                retValue = getNextVisualPositionFrom(-1, Position.Bias.Forward,
                                                     a, WEST, bias);
            } catch (BadLocationException ble) { }
            catch (IllegalArgumentException iae) { }

            if(retValue == -1) {
                // NOTE: this could actually use end offset with backward.
                retValue = getEndOffset() - 1;
                bias[0] = Position.Bias.Forward;
            }
            return retValue;
        } else {
            // locate the child and pass along the request
            View v = getViewAtPoint((int) x, (int) y, alloc);
            if (v != null) {
              return v.viewToModel(x, y, alloc, bias);
            }
        }
        return -1;
    }

    
Provides a way to determine the next visually represented model location that one might place a caret. Some views may not be visible, they might not be in the same order found in the model, or they just might not allow access to some of the locations in the model. This is a convenience method for getNextNorthSouthVisualPositionFrom and getNextEastWestVisualPositionFrom. This method enables specifying a position to convert within the range of >=0. If the value is -1, a position will be calculated automatically. If the value < -1, the BadLocationException will be thrown. 
Params:
  • pos – the position to convert
  • b – a bias value of either Position.Bias.Forward
 or Position.Bias.Backward
  • a – the allocated region to render into
  • direction – the direction from the current position that can
 be thought of as the arrow keys typically found on a keyboard;
 this may be one of the following:
 
      
 
    • SwingConstants.WEST
 
    • SwingConstants.EAST
 
    • SwingConstants.NORTH
 
    • SwingConstants.SOUTH
 
  • biasRet – an array containing the bias that was checked
Throws:
Returns:the location within the model that best represents the next
 location visual position
/**
     * Provides a way to determine the next visually represented model
     * location that one might place a caret.  Some views may not be visible,
     * they might not be in the same order found in the model, or they just
     * might not allow access to some of the locations in the model.
     * This is a convenience method for {@link #getNextNorthSouthVisualPositionFrom}
     * and {@link #getNextEastWestVisualPositionFrom}.
     * This method enables specifying a position to convert
     * within the range of &gt;=0.  If the value is -1, a position
     * will be calculated automatically.  If the value &lt; -1,
     * the {@code BadLocationException} will be thrown.
     *
     * @param pos the position to convert
     * @param b a bias value of either <code>Position.Bias.Forward</code>
     *  or <code>Position.Bias.Backward</code>
     * @param a the allocated region to render into
     * @param direction the direction from the current position that can
     *  be thought of as the arrow keys typically found on a keyboard;
     *  this may be one of the following:
     *  <ul>
     *  <li><code>SwingConstants.WEST</code>
     *  <li><code>SwingConstants.EAST</code>
     *  <li><code>SwingConstants.NORTH</code>
     *  <li><code>SwingConstants.SOUTH</code>
     *  </ul>
     * @param biasRet an array containing the bias that was checked
     * @return the location within the model that best represents the next
     *  location visual position
     * @exception BadLocationException the given position is not a valid
     *                                 position within the document
     * @exception IllegalArgumentException if <code>direction</code> is invalid
     */
    public int getNextVisualPositionFrom(int pos, Position.Bias b, Shape a,
                                         int direction, Position.Bias[] biasRet)
      throws BadLocationException {
        if (pos < -1) {
            throw new BadLocationException("invalid position", pos);
        }
        Rectangle alloc = getInsideAllocation(a);

        switch (direction) {
        case NORTH:
            return getNextNorthSouthVisualPositionFrom(pos, b, a, direction,
                                                       biasRet);
        case SOUTH:
            return getNextNorthSouthVisualPositionFrom(pos, b, a, direction,
                                                       biasRet);
        case EAST:
            return getNextEastWestVisualPositionFrom(pos, b, a, direction,
                                                     biasRet);
        case WEST:
            return getNextEastWestVisualPositionFrom(pos, b, a, direction,
                                                     biasRet);
        default:
            throw new IllegalArgumentException("Bad direction: " + direction);
        }
    }

    
Returns the child view index representing the given
position in the model.  This is implemented to call the
getViewIndexByPosition
method for backward compatibility.

Params:
  • pos – the position >= 0
Returns: index of the view representing the given position, or
  -1 if no view represents that position
Since:1.3
/**
     * Returns the child view index representing the given
     * position in the model.  This is implemented to call the
     * <code>getViewIndexByPosition</code>
     * method for backward compatibility.
     *
     * @param pos the position &gt;= 0
     * @return  index of the view representing the given position, or
     *   -1 if no view represents that position
     * @since 1.3
     */
    public int getViewIndex(int pos, Position.Bias b) {
        if(b == Position.Bias.Backward) {
            pos -= 1;
        }
        if ((pos >= getStartOffset()) && (pos < getEndOffset())) {
            return getViewIndexAtPosition(pos);
        }
        return -1;
    }

    // --- local methods ----------------------------------------------------


    
Tests whether a point lies before the rectangle range.

Params:
  • x – the X coordinate >= 0
  • y – the Y coordinate >= 0
  • alloc – the rectangle
Returns:true if the point is before the specified range
/**
     * Tests whether a point lies before the rectangle range.
     *
     * @param x the X coordinate &gt;= 0
     * @param y the Y coordinate &gt;= 0
     * @param alloc the rectangle
     * @return true if the point is before the specified range
     */
    protected abstract boolean isBefore(int x, int y, Rectangle alloc);

    
Tests whether a point lies after the rectangle range.

Params:
  • x – the X coordinate >= 0
  • y – the Y coordinate >= 0
  • alloc – the rectangle
Returns:true if the point is after the specified range
/**
     * Tests whether a point lies after the rectangle range.
     *
     * @param x the X coordinate &gt;= 0
     * @param y the Y coordinate &gt;= 0
     * @param alloc the rectangle
     * @return true if the point is after the specified range
     */
    protected abstract boolean isAfter(int x, int y, Rectangle alloc);

    
Fetches the child view at the given coordinates.

Params:
  • x – the X coordinate >= 0
  • y – the Y coordinate >= 0
  • alloc – the parent's allocation on entry, which should
  be changed to the child's allocation on exit
Returns:the child view
/**
     * Fetches the child view at the given coordinates.
     *
     * @param x the X coordinate &gt;= 0
     * @param y the Y coordinate &gt;= 0
     * @param alloc the parent's allocation on entry, which should
     *   be changed to the child's allocation on exit
     * @return the child view
     */
    protected abstract View getViewAtPoint(int x, int y, Rectangle alloc);

    
Returns the allocation for a given child.

Params:
  • index – the index of the child, >= 0 && < getViewCount()
  • a –  the allocation to the interior of the box on entry,
  and the allocation of the child view at the index on exit.
/**
     * Returns the allocation for a given child.
     *
     * @param index the index of the child, &gt;= 0 &amp;&amp; &lt; getViewCount()
     * @param a  the allocation to the interior of the box on entry,
     *   and the allocation of the child view at the index on exit.
     */
    protected abstract void childAllocation(int index, Rectangle a);

    
Fetches the child view that represents the given position in
the model.  This is implemented to fetch the view in the case
where there is a child view for each child element.

Params:
  • pos – the position >= 0
  • a –  the allocation to the interior of the box on entry,
  and the allocation of the view containing the position on exit
Returns: the view representing the given position, or
  null if there isn't one
/**
     * Fetches the child view that represents the given position in
     * the model.  This is implemented to fetch the view in the case
     * where there is a child view for each child element.
     *
     * @param pos the position &gt;= 0
     * @param a  the allocation to the interior of the box on entry,
     *   and the allocation of the view containing the position on exit
     * @return  the view representing the given position, or
     *   <code>null</code> if there isn't one
     */
    protected View getViewAtPosition(int pos, Rectangle a) {
        int index = getViewIndexAtPosition(pos);
        if ((index >= 0) && (index < getViewCount())) {
            View v = getView(index);
            if (a != null) {
                childAllocation(index, a);
            }
            return v;
        }
        return null;
    }

    
Fetches the child view index representing the given position in
the model.  This is implemented to fetch the view in the case
where there is a child view for each child element.

Params:
  • pos – the position >= 0
Returns: index of the view representing the given position, or
  -1 if no view represents that position
/**
     * Fetches the child view index representing the given position in
     * the model.  This is implemented to fetch the view in the case
     * where there is a child view for each child element.
     *
     * @param pos the position &gt;= 0
     * @return  index of the view representing the given position, or
     *   -1 if no view represents that position
     */
    protected int getViewIndexAtPosition(int pos) {
        Element elem = getElement();
        return elem.getElementIndex(pos);
    }

    
Translates the immutable allocation given to the view
to a mutable allocation that represents the interior
allocation (i.e. the bounds of the given allocation
with the top, left, bottom, and right insets removed.
It is expected that the returned value would be further
mutated to represent an allocation to a child view.
This is implemented to reuse an instance variable so
it avoids creating excessive Rectangles.  Typically
the result of calling this method would be fed to
the childAllocation method.

Params:
  • a – the allocation given to the view
Returns:the allocation that represents the inside of the
  view after the margins have all been removed; if the
  given allocation was null,
  the return value is null
/**
     * Translates the immutable allocation given to the view
     * to a mutable allocation that represents the interior
     * allocation (i.e. the bounds of the given allocation
     * with the top, left, bottom, and right insets removed.
     * It is expected that the returned value would be further
     * mutated to represent an allocation to a child view.
     * This is implemented to reuse an instance variable so
     * it avoids creating excessive Rectangles.  Typically
     * the result of calling this method would be fed to
     * the <code>childAllocation</code> method.
     *
     * @param a the allocation given to the view
     * @return the allocation that represents the inside of the
     *   view after the margins have all been removed; if the
     *   given allocation was <code>null</code>,
     *   the return value is <code>null</code>
     */
    protected Rectangle getInsideAllocation(Shape a) {
        if (a != null) {
            // get the bounds, hopefully without allocating
            // a new rectangle.  The Shape argument should
            // not be modified... we copy it into the
            // child allocation.
            Rectangle alloc;
            if (a instanceof Rectangle) {
                alloc = (Rectangle) a;
            } else {
                alloc = a.getBounds();
            }

            childAlloc.setBounds(alloc);
            childAlloc.x += getLeftInset();
            childAlloc.y += getTopInset();
            childAlloc.width -= getLeftInset() + getRightInset();
            childAlloc.height -= getTopInset() + getBottomInset();
            return childAlloc;
        }
        return null;
    }

    
Sets the insets from the paragraph attributes specified in
the given attributes.

Params:
  • attr – the attributes
/**
     * Sets the insets from the paragraph attributes specified in
     * the given attributes.
     *
     * @param attr the attributes
     */
    protected void setParagraphInsets(AttributeSet attr) {
        // Since version 1.1 doesn't have scaling and assumes
        // a pixel is equal to a point, we just cast the point
        // sizes to integers.
        top = (short) StyleConstants.getSpaceAbove(attr);
        left = (short) StyleConstants.getLeftIndent(attr);
        bottom = (short) StyleConstants.getSpaceBelow(attr);
        right = (short) StyleConstants.getRightIndent(attr);
    }

    
Sets the insets for the view.

Params:
  • top – the top inset >= 0
  • left – the left inset >= 0
  • bottom – the bottom inset >= 0
  • right – the right inset >= 0
/**
     * Sets the insets for the view.
     *
     * @param top the top inset &gt;= 0
     * @param left the left inset &gt;= 0
     * @param bottom the bottom inset &gt;= 0
     * @param right the right inset &gt;= 0
     */
    protected void setInsets(short top, short left, short bottom, short right) {
        this.top = top;
        this.left = left;
        this.right = right;
        this.bottom = bottom;
    }

    
Gets the left inset.

Returns:the inset >= 0
/**
     * Gets the left inset.
     *
     * @return the inset &gt;= 0
     */
    protected short getLeftInset() {
        return left;
    }

    
Gets the right inset.

Returns:the inset >= 0
/**
     * Gets the right inset.
     *
     * @return the inset &gt;= 0
     */
    protected short getRightInset() {
        return right;
    }

    
Gets the top inset.

Returns:the inset >= 0
/**
     * Gets the top inset.
     *
     * @return the inset &gt;= 0
     */
    protected short getTopInset() {
        return top;
    }

    
Gets the bottom inset.

Returns:the inset >= 0
/**
     * Gets the bottom inset.
     *
     * @return the inset &gt;= 0
     */
    protected short getBottomInset() {
        return bottom;
    }

    
Returns the next visual position for the cursor, in either the
north or south direction.

Params:
  • pos – the position to convert >= 0
  • b – a bias value of either Position.Bias.Forward
 or Position.Bias.Backward
  • a – the allocated region to render into
  • direction – the direction from the current position that can
 be thought of as the arrow keys typically found on a keyboard;
 this may be one of the following:
 
      
 
    • SwingConstants.NORTH
 
    • SwingConstants.SOUTH
 
  • biasRet – an array containing the bias that was checked
Throws:
See Also:
Returns:the location within the model that best represents the next
 north or south location
Returns:the next position west of the passed in position
/**
     * Returns the next visual position for the cursor, in either the
     * north or south direction.
     *
     * @param pos the position to convert &gt;= 0
     * @param b a bias value of either <code>Position.Bias.Forward</code>
     *  or <code>Position.Bias.Backward</code>
     * @param a the allocated region to render into
     * @param direction the direction from the current position that can
     *  be thought of as the arrow keys typically found on a keyboard;
     *  this may be one of the following:
     *  <ul>
     *  <li><code>SwingConstants.NORTH</code>
     *  <li><code>SwingConstants.SOUTH</code>
     *  </ul>
     * @param biasRet an array containing the bias that was checked
     * @return the location within the model that best represents the next
     *  north or south location
     * @exception BadLocationException
     * @exception IllegalArgumentException if <code>direction</code> is invalid
     * @see #getNextVisualPositionFrom
     *
     * @return the next position west of the passed in position
     */
    protected int getNextNorthSouthVisualPositionFrom(int pos, Position.Bias b,
                                                      Shape a, int direction,
                                                      Position.Bias[] biasRet)
                                                throws BadLocationException {
        return Utilities.getNextVisualPositionFrom(
                            this, pos, b, a, direction, biasRet);
    }

    
Returns the next visual position for the cursor, in either the
east or west direction.

Params:
  • pos – the position to convert >= 0
  • b – a bias value of either Position.Bias.Forward
 or Position.Bias.Backward
  • a – the allocated region to render into
  • direction – the direction from the current position that can
 be thought of as the arrow keys typically found on a keyboard;
 this may be one of the following:
 
      
 
    • SwingConstants.WEST
 
    • SwingConstants.EAST
 
  • biasRet – an array containing the bias that was checked
Throws:
See Also:
Returns:the location within the model that best represents the next
 west or east location
/**
     * Returns the next visual position for the cursor, in either the
     * east or west direction.
     *
    * @param pos the position to convert &gt;= 0
     * @param b a bias value of either <code>Position.Bias.Forward</code>
     *  or <code>Position.Bias.Backward</code>
     * @param a the allocated region to render into
     * @param direction the direction from the current position that can
     *  be thought of as the arrow keys typically found on a keyboard;
     *  this may be one of the following:
     *  <ul>
     *  <li><code>SwingConstants.WEST</code>
     *  <li><code>SwingConstants.EAST</code>
     *  </ul>
     * @param biasRet an array containing the bias that was checked
     * @return the location within the model that best represents the next
     *  west or east location
     * @exception BadLocationException
     * @exception IllegalArgumentException if <code>direction</code> is invalid
     * @see #getNextVisualPositionFrom
     */
    protected int getNextEastWestVisualPositionFrom(int pos, Position.Bias b,
                                                    Shape a,
                                                    int direction,
                                                    Position.Bias[] biasRet)
                                                throws BadLocationException {
        return Utilities.getNextVisualPositionFrom(
                            this, pos, b, a, direction, biasRet);
    }

    
Determines in which direction the next view lays.
Consider the View at index n. Typically the
Views are layed out from left to right,
so that the View to the EAST will be
at index n + 1, and the View to the WEST
will be at index n - 1. In certain situations,
such as with bidirectional text, it is possible
that the View to EAST is not at index n + 1,
but rather at index n - 1, or that the View
to the WEST is not at index n - 1, but index n + 1.
In this case this method would return true, indicating the
Views are layed out in descending order.


This unconditionally returns false, subclasses should override this
method if there is the possibility for laying Views in
descending order.

Params:
  • position – position into the model
  • bias – either Position.Bias.Forward or
         Position.Bias.Backward
Returns:false
/**
     * Determines in which direction the next view lays.
     * Consider the <code>View</code> at index n. Typically the
     * <code>View</code>s are layed out from left to right,
     * so that the <code>View</code> to the EAST will be
     * at index n + 1, and the <code>View</code> to the WEST
     * will be at index n - 1. In certain situations,
     * such as with bidirectional text, it is possible
     * that the <code>View</code> to EAST is not at index n + 1,
     * but rather at index n - 1, or that the <code>View</code>
     * to the WEST is not at index n - 1, but index n + 1.
     * In this case this method would return true, indicating the
     * <code>View</code>s are layed out in descending order.
     * <p>
     * This unconditionally returns false, subclasses should override this
     * method if there is the possibility for laying <code>View</code>s in
     * descending order.
     *
     * @param position position into the model
     * @param bias either <code>Position.Bias.Forward</code> or
     *          <code>Position.Bias.Backward</code>
     * @return false
     */
    protected boolean flipEastAndWestAtEnds(int position,
                                            Position.Bias bias) {
        return false;
    }


    // ---- member variables ---------------------------------------------


    private static View[] ZERO = new View[0];

    private View[] children;
    private int nchildren;
    private short left;
    private short right;
    private short top;
    private short bottom;
    private Rectangle childAlloc;
}