import cn.hutool.core.util.StrUtil;
import cn.hutool.json.JSONUtil;

public class Test {
    public static void main(String[] args) {
        String str = "张三,男,18";
        char separator = ',';
        String[] strings = StrUtil.splitToArray(str, separator);
        String s = JSONUtil.toJsonStr(strings);
        System.out.println(s);
    }
}

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