}
        });
        return resultBuf.toString();
    }

    /**
     * Adds a score booster.
     * @param scoreBooster The score booster.
     */
    protected void addScoreBooster(final ScoreBooster scoreBooster) {
        scoreBoosterList.add(scoreBooster);
        scoreBoosterList.sort((b1, b2) -> b2.getPriority() - b1.getPriority());
    }

    /**
     * Enables this score booster.
     */
    protected void enable() {
        final ScoreUpdater scoreUpdater = ComponentUtil.getComponent("scoreUpdater");
        scoreUpdater.addScoreBooster(this);
    }

    /**
     * Updates the score of documents.
     * @param params The parameters for the update.
     * @return The number of updated documents.
     */