String字符串拼接

String字符串拼接操作

        List<Integer> list = Arrays.asList(1, 2, 3, 4, 5);
        System.out.println(list);

        //常用操作拼接
        StringBuilder builder = new StringBuilder();
        for(Integer index :list){
            builder.append(String.valueOf(index)).append(",");
        }
        String str = builder.subSequence(0, builder.length() - 1).toString();
        System.out.println(str);

        // StringJoiner 拼接 ,JDK1.8 提供

        StringJoiner joiner = new StringJoiner(",");
        for (Integer s : list) {
            joiner.add(String.valueOf(s));
        }
        System.out.println(joiner);
        // java8 Stream 拼接
        String collect = list.stream().map(String::valueOf).collect(Collectors.joining(","));
        System.out.println(collect);

        // guava joiner  拼接 字符串
        // com.google.common.base.Joiner;
        String join = Joiner.on(",").join(list);
        System.out.println(join);