StringJoiner sj = new StringJoiner(",");
        sj.add("我愛你");
        sj.add("我的");
        sj.add("祖國");
        System.out.println(sj);

執行如下：
-------------------------
我愛你,我的,祖國
-------------------------

StringJoiner stj1 = new StringJoiner(",", "[", "]");
        stj.setEmptyValue("empty");
        System.out.println(stj1.toString());

-執行如下：
---------------------
[]
---------------------

 StringJoiner stj = new StringJoiner(",");
        System.out.println(stj.toString());

-執行如下：
----------------------
輸出空白字符串
----------------------

StringJoiner stj = new StringJoiner(",", "--", "++");
        stj.add("hello");
        stj.add("world");
        stj.add("歡迎使用StringJoiner");
        System.out.println(stj);

-執行如下：
------------------------------------------
--hello,world,歡迎使用StringJoiner++
------------------------------------------

 StringJoiner sj = new StringJoiner(",");
        sj.add("我愛你");
        sj.add("我的");
        sj.add("祖國");

        StringJoiner stj = new StringJoiner(",", "--", "++");
        stj.add("hello");
        stj.add("world");
        stj.add("歡迎使用StringJoiner");
        
        System.out.println(sj.merge(stj));
-執行如下：
--------------------------------------------------------
我愛你,我的,祖國,hello,world,歡迎使用StringJoiner
--------------------------------------------------------