COWMAN-CHIANG

Ref:

1. java.util.Arrays.asList用法及注意事项

2. java集合中部分异常java.lang.UnsupportedOperationException一个共同点

Because the ArrayList made by Arrays.asList function could not be modified anymore…

Ref: 剑飘江湖的博客 – JSON格式数据中特殊字符的处理

   public static String stringToJson(String s) {
    if (StringUtils.isEmpty(s)) {
        return s;
    }
    StringBuffer sb = new StringBuffer ();
    for (int i=0; i<s.length(); i++) {

        char c = s.charAt(i);
        switch (c) {
            case '"':
                sb.append("\"");
                break;
            /*case '\':   
                sb.append("\\");
                break;
            case '/':
                sb.append("\/");
                break;*/
            case 'b':      
                sb.append("\b");
                break;
            case 'f':      
                sb.append("\f");
                break;
            case 'n':
                sb.append("\n"); 
                break;
            case 'r':      
                sb.append("\r");
                break;
            case 't':      
                sb.append("\t");
                break;
            default:
                sb.append(c);
        }
    }
    return sb.toString();
}

Ref: stackoverflow: Initialization of an ArrayList in one line

List<String> places = Arrays.asList("Buenos Aires", "Córdoba", "La Plata");

Ref: Java Hashmap: How to get key from value?

private Object getKeyFromValue(Map map, Object value) {
    for (Object object : map.keySet()) {
        if (map.get(object).equals(value)) {
            return object;
        }
    }
    return null;
}

Ref: stackoverflow：How to check whether a given string is valid JSON in Java

public boolean isJSONValid(String test) {
  try {
      new JSONObject(test);
  } catch (JSONException ex) {
      // edited, to include @Arthur's comment
      // e.g. in case JSONArray is valid as well...
      try {
          new JSONArray(test);
      } catch (JSONException ex1) {
          return false;
      }
  }
  return true;
}