Record some of the APIs you encounter in work learning, tips

　　Usually in the study encountered some very interesting code writing. Record down and raise the level. Of course because I am a novice, may have more strange suspicion.

Using the pattern class to match regular expression rules

int num = 1= "[0-9]+"; // fill in the required regular expression rules
Pattern pattern = Pattern.compile (REG); Boolean yn=pattern.matcher (string.valueof (num)). matches (); System.out.println (YN);

Comparer definition

comparator<integer> CP = (x, y) x > y? 1: (x < y? -1:0);

Swap (ARR,A,B) does not use temporary variable notation

/**@param@param @param*/Public  void swap (intintint  b) {    ^= arr[b];     ^= Arr[a];     ^= arr[b];}

String.Format

* 100)

You can output the data in a formatted format, and the results appear as follows:

Record some of the APIs you encounter in work learning, tips