//已字符串分隔方法最新 方法
StringJoiner stringJoiner=new StringJoiner(",");
stringJoiner.add("a");
stringJoiner.add("b");
System.out.println(stringJoiner.toString()); //老方法
StringBuffer stringBuffer=new StringBuffer();
stringBuffer.append("a").append(",").append("b");
看来还是要多研究多用才能发现好东西哇!!!