java - Regex - starts with OPERATION and must be followed by either an integer or double -
so have follow input string operation: 12, 12.32, 54.3332 operation can of min, max, sum. regex should accept strings start of 3 words follow colon , followed either integer or double. i have been googling , fidling around hours before decided turn guys. thanks time! edit: so far have ended regex ^[max:sum:average:min:(\\d+(\\.\\d+)?), ]+$ it matches "max: " correct "max:" , "ma: . matches strings of following format : "max: 12, 12.3323......" you misunderstand meaning of [] . these refer single character alternatives. so [max:sum:average:min:(\\d+(\\.\\d+)?), ] either m or a or x or .... mmmmm should match. you may want more this: ^(max|sum|average|min): (\\d+(\\.\\d+)?(, (?=.)|$))+$ explanation: (max|sum|average|min) either max , sum , average or min . ": " refers actual characters : , space. \\d+(\\.\\d+)? had before. ", " refers actual characters , , space. (?=.) look-ahea...