A DESCRIPTION OF THE PROBLEM :
Deprecated align variable not allows LEADING or TRAILING values.


EXPECTED VERSUS ACTUAL BEHAVIOR :
EXPECTED -
    /**
     * <code>align</code> is the property that determines
     * how each row distributes empty space.
     * It can be one of the following values:
     * <ul>
     * <code>LEFT</code>
     * <code>RIGHT</code>
     * <code>CENTER</code>
     * </ul>
     *
     * @serial
     * @see #getAlignment
     * @see #setAlignment
     */
    int align; // This is for 1.1 serialization compatibility

ACTUAL -
    /**
     * <code>align</code> is the property that determines
     * how each row distributes empty space.
     * It can be one of the following values:
     * <ul>
     * <code>LEFT</code>
     * <code>RIGHT</code>
     * <code>CENTER</code>
     * <code>LEADING</code>
     * <code>TRAILING</code>
     * </ul>
     *
     * @serial
     * @see #getAlignment
     * @see #setAlignment
     */
    int align; // This is for 1.1 serialization compatibility


URL OF FAULTY DOCUMENTATION :
FlowLayout source code