Java8 List转字符串 Java8 将List转换为用逗号隔开的字符串的多种方法

1.使用谷歌的Joiner转换

public static <T> String parseListToStr(List<T> list){

String result = Joiner.on(",").join(list);

return result;

}

2.使用lambda表达式遍历集合

public static <T> String parseListToStr2(List<T> list){

StringBuffer sb = new StringBuffer();

list.stream().forEach(str->{

sb.append(str).append(",");

});

sb.deleteCharAt(sb.length()-1);

return sb.toString();

}

3.直接使用stream流实现

public static <T> String parseListToStr3(List<T> list){

String result = list.stream().map(String::valueOf).collect(Collectors.joining(","));

return result;

}

或

public static <T> String parseListToStr3(List<T> list){

String result = list.stream().map(T::getName).collect(Collectors.joining(","));

return result;

}

4.使用for循环遍历集合

public static <T> String parseListToStr(List<T> list){

StringBuffer sb = new StringBuffer();

if(listIsNotNull(list)) {

for(int i=0;i<=list.size()-1;i++){

if(i<list.size()-1){

sb.append(list.get(i) + ",");

}else {

sb.append(list.get(i));

}

}

}

return sb.toString();

}

注意：在转换集合前应该都统一做判空处理