用StringJoiner 做字符串拼接
- API 包括
setEmptyValue:设置空值
toString:转换成 String
add:添加字符串
merge:从另一个 StringJoiner 合并
length:长度(包括前缀后缀)
StringJoiner stringJoiner = new StringJoiner(",").add("hello").add("world").add("moximoxi");
输出结果:hello,world,moximoxi
StringJoiner stringJoiner = new StringJoiner(",", "[", "]");
stringJoiner.add("hello");
stringJoiner.add("world");
stringJoiner.add("moximoxi");
输出结果:[hello,world,moximoxi]
- JDK1.8 String也封装了stringJoiner 让拼接操作变得更简单
String str = String.join(",", "hello", "world", "moximoxi");