Java逗号分隔的字符串和数组的转换

1、将逗号分隔的字符串转换为List

String str = "a,b,c"; 
 
List<String> result = Arrays.asList(str.split(","));

2、将List转换为逗号分隔的字符串

（1） 利用Guava的Joiner

List<String> list = new ArrayList<String>(); 
list.add("a"); 
list.add("b"); 
list.add("c"); 
 
String str = Joiner.on(",").join(list); 

（2）利用Apache Commons的StringUtils

List<String> list = new ArrayList<String>(); 
list.add("a"); 
list.add("b"); 
list.add("c"); 
 
String str = StringUtils.join(list.toArray(), ",");