Question

可能重复：
  Assigning an array to an ArrayList in Java
  java: how to convert this string to ArrayList?
  How to convert a String into an ArrayList?

我有String：

["word1","word2","word3","word4"]

上述文字不是数组，而是通过GCM（Google Cloud Messaging）通信从服务器返回的字符串。更具体地说，在GCM课程中我有这个：

protected void onMessage(Context context, Intent intent) {

String message = intent.getExtras().getString("cabmate");

   }

String消息的值为["word1","word2","word3","word4"]

有没有办法在Java中用List或ArrayList转换它？

Answer 1

Arrays.asList(String[])

返回List<String>。

Answer 2

String wordString = "[\"word1\", \"word2\", \"word3\", \"word4\"]";
String[] words = wordString.substring(1, wordString.length() - 2).replaceAll("\"", "").split(", ");
List<String> wordList = new ArrayList<>();
Collections.addAll(wordList, words);

这将做你想要的。请注意我故意拆分", "以删除空格，在for-each循环中为每个字符串调用.trim()然后添加到List可能更为谨慎。 / p>

Answer 3

这样的事情：

/*
@invariant The "Word" fields cannot have commas in thier values or the conversion
to a list will cause bad field breaks. CSV data sucks...
*/
public List<String> stringFormatedToStringList(String s) {
  // oneliner for the win:
  return Arrays.asList(s.substring(1,s.length()-1).replaceAll("\"","").split(","));
  // .substring  removes the first an last characters from the string ('[' & ']')
  // .replaceAll removes all quotation marks from the string (replaces with empty string)
  // .split brakes the string into a string array on commas (omitting the commas)
  // Arrays.asList converts the array to a List
}

如何将字符串数组转换为ArrayList

3 个答案: