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class NestableDelegate {
    /**
     * Returns the full message contained by the <code>Nestable</code> and any nested <code>Throwable</code>s.
     * 
     * @param baseMsg
     *            the base message to use when creating the full message. Should be generally be called via
     *            <code>nestableHelper.getMessage(super.getMessage())</code>, where <code>super</code> is an
     *            instance of {@link java.lang.Throwable}.
     * @return The concatenated message for this and all nested <code>Throwable</code>s
     * @since 2.0
     */
    public String getMessage(String baseMsg) {
        Throwable nestedCause = ExceptionUtils.getCause(this.nestable);
        String causeMsg = nestedCause == null ? null : nestedCause.getMessage();
        if (nestedCause == null || causeMsg == null) {
            return baseMsg; // may be null, which is a valid result
        }
        if (baseMsg == null) {
            return causeMsg;
        }
        return baseMsg + ": " + causeMsg;
    }

}