class WrapLayout extends FlowLayout {

    private Dimension preferredLayoutSize;

    /**
     * Constructs a new <code>WrapLayout</code> with a left
     * alignment and a default 5-unit horizontal and vertical gap.
     */
    public WrapLayout() {
        super();
    }

    /**
     * Constructs a new <code>FlowLayout</code> with the specified
     * alignment and a default 5-unit horizontal and vertical gap.
     * The value of the alignment argument must be one of
     * <code>WrapLayout</code>, <code>WrapLayout</code>,
     * or <code>WrapLayout</code>.
     *
     * @param align the alignment value
     */
    public WrapLayout(int align) {
        super(align);
    }

    /**
     * Creates a new flow layout manager with the indicated alignment
     * and the indicated horizontal and vertical gaps.
     * <p>
     * The value of the alignment argument must be one of
     * <code>WrapLayout</code>, <code>WrapLayout</code>,
     * or <code>WrapLayout</code>.
     *
     * @param align the alignment value
     * @param hgap  the horizontal gap between components
     * @param vgap  the vertical gap between components
     */
    public WrapLayout(int align, int hgap, int vgap) {
        super(align, hgap, vgap);
    }

    /**
     * Returns the preferred dimensions for this layout given the
     * <i>visible</i> components in the specified target container.
     *
     * @param target the component which needs to be laid out
     * @return the preferred dimensions to lay out the
     * subcomponents of the specified container
     */
    @Override
    public Dimension preferredLayoutSize(Container target) {
        return layoutSize(target, true);
    }

    /**
     * Returns the minimum dimensions needed to layout the <i>visible</i>
     * components contained in the specified target container.
     *
     * @param target the component which needs to be laid out
     * @return the minimum dimensions to lay out the
     * subcomponents of the specified container
     */
    @Override
    public Dimension minimumLayoutSize(Container target) {
        return layoutSize(target, false);
    }

    /**
     * Returns the minimum or preferred dimension needed to layout the target
     * container.
     *
     * @param target    target to get layout size for
     * @param preferred should preferred size be calculated
     * @return the dimension to layout the target container
     */
    private Dimension layoutSize(Container target, boolean preferred) {
        synchronized (target.getTreeLock()) {
            //  Each row must fit with the width allocated to the containter.
            //  When the container width = 0, the preferred width of the container
            //  has not yet been calculated so lets ask for the maximum.

            int targetWidth = target.getSize().width;

            if (targetWidth == 0) {
                targetWidth = Integer.MAX_VALUE;
            }

            int hgap = getHgap();
            int vgap = getVgap();
            Insets insets = target.getInsets();
            int horizontalInsetsAndGap = insets.left + insets.right + (hgap * 2);
            int maxWidth = targetWidth - horizontalInsetsAndGap;

            //  Fit components into the allowed width

            Dimension dim = new Dimension(0, 0);
            int rowWidth = 0;
            int rowHeight = 0;

            int nmembers = target.getComponentCount();

            for (int i = 0; i < nmembers; i++) {
                Component m = target.getComponent(i);

                if (m.isVisible()) {
                    Dimension d = preferred ? m.getPreferredSize() : m.getMinimumSize();

                    //  Can't add the component to current row. Start a new row.

                    if (rowWidth + d.width > maxWidth) {
                        addRow(dim, rowWidth, rowHeight);
                        rowWidth = 0;
                        rowHeight = 0;
                    }

                    //  Add a horizontal gap for all components after the first

                    if (rowWidth != 0) {
                        rowWidth += hgap;
                    }

                    rowWidth += d.width;
                    rowHeight = Math.max(rowHeight, d.height);
                }
            }

            addRow(dim, rowWidth, rowHeight);

            dim.width += horizontalInsetsAndGap;
            dim.height += insets.top + insets.bottom + vgap * 2;

            //When using a scroll pane or the DecoratedLookAndFeel we need to
            //make sure the preferred size is less than the size of the
            //target containter so shrinking the container size works
            //correctly. Removing the horizontal gap is an easy way to do this.

            dim.width -= (hgap + 1);

            return dim;
        }
    }

    /**
     * Layout the components in the Container using the layout logic of the
     * parent FlowLayout class.
     *
     * @param target the Container using this WrapLayout
     */
    @Override
    public void layoutContainer(Container target) {<FILL_FUNCTION_BODY>}

    /*
     *  A new row has been completed. Use the dimensions of this row
     *  to update the preferred size for the container.
     *
     *  @param dim update the width and height when appropriate
     *  @param rowWidth the width of the row to add
     *  @param rowHeight the height of the row to add
     */
    private void addRow(Dimension dim, int rowWidth, int rowHeight) {
        dim.width = Math.max(dim.width, rowWidth);

        if (dim.height > 0) {
            dim.height += getVgap();
        }

        dim.height += rowHeight;
    }
}

        Dimension size = preferredLayoutSize(target);

        //  When a frame is minimized or maximized the preferred size of the
        //  Container is assumed not to change. Therefore we need to force a
        //  validate() to make sure that space, if available, is allocated to
        //  the panel using a WrapLayout.

        if (size.equals(preferredLayoutSize)) {
            super.layoutContainer(target);
        } else {
            preferredLayoutSize = size;
            Container top = target;

            while (top.getParent() != null) {
                top = top.getParent();
            }

            top.validate();
        }
    
<methods>public void <init>() ,public void <init>(int) ,public void <init>(int, int, int) ,public void addLayoutComponent(java.lang.String, java.awt.Component) ,public boolean getAlignOnBaseline() ,public int getAlignment() ,public int getHgap() ,public int getVgap() ,public void layoutContainer(java.awt.Container) ,public java.awt.Dimension minimumLayoutSize(java.awt.Container) ,public java.awt.Dimension preferredLayoutSize(java.awt.Container) ,public void removeLayoutComponent(java.awt.Component) ,public void setAlignOnBaseline(boolean) ,public void setAlignment(int) ,public void setHgap(int) ,public void setVgap(int) ,public java.lang.String toString() <variables>public static final int CENTER,public static final int LEADING,public static final int LEFT,public static final int RIGHT,public static final int TRAILING,int align,private boolean alignOnBaseline,private static final int currentSerialVersion,int hgap,int newAlign,private int serialVersionOnStream,private static final long serialVersionUID,int vgap