WrapLayout

/** * @author Administrator * */public class WrapLayout extends FlowLayout {

    public WrapLayout() {        super();    }

    public WrapLayout(int align) {        super(align);    }

    public WrapLayout(int align, int hgap, int vgap) {        super(align, hgap, vgap);    }

    public Dimension minimumLayoutSize(Container target) {        return computeSize(target, false);    }

    public Dimension preferredLayoutSize(Container target) {        return computeSize(target, true);    }

    private Dimension computeSize(Container target, boolean minimum) {        synchronized (target.getTreeLock()) {            int hgap = getHgap();            int vgap = getVgap();            int w = target.getWidth();

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

            Insets insets = target.getInsets();            if (insets == null) {                insets = new Insets(0, 0, 0, 0);            }            int reqdWidth = 0;

            int maxwidth = w - (insets.left + insets.right + hgap * 2);            int n = target.getComponentCount();            int x = 0;            int y = insets.top;            int rowHeight = 0;

            for (int i = 0; i < n; i++) {                Component c = target.getComponent(i);                if (c.isVisible()) {                    Dimension d =                            minimum ? c.getMinimumSize() : c.getPreferredSize();                    if ((x == 0) || ((x + d.width) <= maxwidth)) {                        if (x > 0) {                            x += hgap;                        }                        x += d.width;                        rowHeight = Math.max(rowHeight, d.height);                    } else {                        x = d.width;                        y += vgap + rowHeight;                        rowHeight = d.height;                    }                    reqdWidth = Math.max(reqdWidth, x);                }            }            y += rowHeight;            return new Dimension(reqdWidth + insets.left + insets.right, y);        }    }}