Javascript判断Crontab表达式是否合法

来源：互联网发布：为什么知乎很多反政府编辑：程序博客网时间：2024/06/06 20:20

这段时间在做Quartz任务调度，使用的Crontab表达式实现的。Crontab由前端页面输入，作为参数穿入后台。
虽然Quartz具有校验Crontab表达式的方法，如下：

boolean cronExpressionFlag = CronExpression.isValidExpression(crontab);

但是我一直想在前端直接验证，即不需要通过异步的方式向后台获取验证结果，找了好久，发现没有现成的框架可以使用，于是自己根据网上搜索到的资料，写了这个js脚本。
这个脚本目前对日和星期的判断还有点小问题，不过不影响使用。
以后如果有时间，继续完善这个脚本，废话不多说了，上代码：

    function cronValidate() {        var cron = $("#cron").val();        var result = CronExpressionValidator.validateCronExpression(cron);        if(result == true){            alert("格式正确");          }        else{            alert("格式错误");        }        return CronExpressionValidator.validateCronExpression(cron);      }     function CronExpressionValidator() {      }      CronExpressionValidator.validateCronExpression = function(value) {          var results = true;          if (value == null || value.length == 0) {              return false;          }          // split and test length          var expressionArray = value.split(" ");          var len = expressionArray.length;          if ((len != 6) && (len != 7)) {              return false;          }          // check only one question mark          var match = value.match(/\?/g);          if (match != null && match.length > 1) {              return false;          }          // check only one question mark          var dayOfTheMonthWildcard = "";          // if appropriate length test parts          // [0] Seconds 0-59 , - * /          if (CronExpressionValidator.isNotWildCard(expressionArray[0], /[\*]/gi)) {              if (!CronExpressionValidator.segmentValidator("([0-9\\\\,-\\/])", expressionArray[0], [0, 59], "seconds")) {                  return false;              }          }          // [1] Minutes 0-59 , - * /          if (CronExpressionValidator.isNotWildCard(expressionArray[1], /[\*]/gi)) {              if (!CronExpressionValidator.segmentValidator("([0-9\\\\,-\\/])", expressionArray[1], [0, 59], "minutes")) {                  return false;              }          }          // [2] Hours 0-23 , - * /          if (CronExpressionValidator.isNotWildCard(expressionArray[2], /[\*]/gi)) {              if (!CronExpressionValidator.segmentValidator("([0-9\\\\,-\\/])", expressionArray[2], [0, 23], "hours")) {                  return false;              }          }          // [3] Day of month 1-31 , - * ? / L W C          if (CronExpressionValidator.isNotWildCard(expressionArray[3], /[\*\?]/gi)) {              if (!CronExpressionValidator.segmentValidator("([0-9LWC\\\\,-\\/])", expressionArray[3], [1, 31], "days of the month")) {                  return false;              }          } else {              dayOfTheMonthWildcard = expressionArray[3];          }          // [4] Month 1-12 or JAN-DEC , - * /          if (CronExpressionValidator.isNotWildCard(expressionArray[4], /[\*]/gi)) {              expressionArray[4] = CronExpressionValidator.convertMonthsToInteger(expressionArray[4]);              if (!CronExpressionValidator.segmentValidator("([0-9\\\\,-\\/])", expressionArray[4], [1, 12], "months")) {                  return false;              }          }          // [5] Day of week 1-7 or SUN-SAT , - * ? / L C #          if (CronExpressionValidator.isNotWildCard(expressionArray[5], /[\*\?]/gi)) {              expressionArray[5] = CronExpressionValidator.convertDaysToInteger(expressionArray[5]);              if (!CronExpressionValidator.segmentValidator("([0-9LC#\\\\,-\\/])", expressionArray[5], [1, 7], "days of the week")) {                  return false;              }          } else {              if (dayOfTheMonthWildcard == String(expressionArray[5])) {                  return false;              }          }          // [6] Year empty or 1970-2099 , - * /          if (len == 7) {              if (CronExpressionValidator.isNotWildCard(expressionArray[6], /[\*]/gi)) {                  if (!CronExpressionValidator.segmentValidator("([0-9\\\\,-\\/])", expressionArray[6], [1970, 2099], "years")) {                      return false;                  }              }          }          return true;      }      // ----------------------------------      // isNotWildcard 静态方法;      // ----------------------------------      CronExpressionValidator.isNotWildCard = function(value, expression) {          var match = value.match(expression);          return (match == null || match.length == 0) ? true : false;      }      // ----------------------------------      // convertDaysToInteger 静态方法;      // ----------------------------------      CronExpressionValidator.convertDaysToInteger = function(value) {          var v = value;          v = v.replace(/SUN/gi, "1");          v = v.replace(/MON/gi, "2");          v = v.replace(/TUE/gi, "3");          v = v.replace(/WED/gi, "4");          v = v.replace(/THU/gi, "5");          v = v.replace(/FRI/gi, "6");          v = v.replace(/SAT/gi, "7");          return v;      }      // ----------------------------------      // convertMonthsToInteger 静态方法;      // ----------------------------------      CronExpressionValidator.convertMonthsToInteger = function(value) {          var v = value;          v = v.replace(/JAN/gi, "1");          v = v.replace(/FEB/gi, "2");          v = v.replace(/MAR/gi, "3");          v = v.replace(/APR/gi, "4");          v = v.replace(/MAY/gi, "5");          v = v.replace(/JUN/gi, "6");          v = v.replace(/JUL/gi, "7");          v = v.replace(/AUG/gi, "8");          v = v.replace(/SEP/gi, "9");          v = v.replace(/OCT/gi, "10");          v = v.replace(/NOV/gi, "11");          v = v.replace(/DEC/gi, "12");          return v;      }      // ----------------------------------      // segmentValidator 静态方法;      // ----------------------------------      CronExpressionValidator.segmentValidator = function(expression, value, range, segmentName) {          var v = value;          var numbers = new Array();          // first, check for any improper segments          var reg = new RegExp(expression, "gi");          if (!reg.test(v)) {               return false;          }          // check duplicate types          // check only one L          var dupMatch = value.match(/L/gi);          if (dupMatch != null && dupMatch.length > 1) {              return false;          }          // look through the segments          // break up segments on ','          // check for special cases L,W,C,/,#,-          var split = v.split(",");          var i = -1;          var l = split.length;          var match;          while (++i < l) {              // set vars              var checkSegment = split[i];              var n;              var pattern = /(\w*)/;              match = pattern.exec(checkSegment);              // if just number              pattern = /(\w*)\-?\d+(\w*)/;              match = pattern.exec(checkSegment);              if (match                      && match[0] == checkSegment                      && checkSegment.indexOf("L") == -1                      && checkSegment.indexOf("l") == -1                      && checkSegment.indexOf("C") == -1                      && checkSegment.indexOf("c") == -1                      && checkSegment.indexOf("W") == -1                      && checkSegment.indexOf("w") == -1                      && checkSegment.indexOf("/") == -1                      && (checkSegment.indexOf("-") == -1 || checkSegment                              .indexOf("-") == 0) && checkSegment.indexOf("#") == -1) {                  n = match[0];                  if (n && !(isNaN(n)))                      numbers.push(n);                  else if (match[0] == "0")                      numbers.push(n);                  continue;              }      // includes L, C, or w              pattern = /(\w*)L|C|W(\w*)/i;              match = pattern.exec(checkSegment);              if (match                      && match[0] != ""                      && (checkSegment.indexOf("L") > -1                              || checkSegment.indexOf("l") > -1                              || checkSegment.indexOf("C") > -1                              || checkSegment.indexOf("c") > -1                              || checkSegment.indexOf("W") > -1 || checkSegment                              .indexOf("w") > -1)) {                  // check just l or L                  if (checkSegment == "L" || checkSegment == "l")                      continue;                  pattern = /(\w*)\d+(l|c|w)?(\w*)/i;                  match = pattern.exec(checkSegment);                  // if something before or after                  if (!match || match[0] != checkSegment) {                       continue;                  }                  // get the number                  var numCheck = match[0];                  numCheck = numCheck.replace(/(l|c|w)/ig, "");                  n = Number(numCheck);                  if (n && !(isNaN(n)))                      numbers.push(n);                  else if (match[0] == "0")                      numbers.push(n);                  continue;              }              var numberSplit;              // includes /              if (checkSegment.indexOf("/") > -1) {                  // take first #                  numberSplit = checkSegment.split("/");                  if (numberSplit.length != 2) {                       continue;                  } else {                      n = numberSplit[0];                      if (n && !(isNaN(n)))                          numbers.push(n);                      else if (numberSplit[0] == "0")                          numbers.push(n);                      continue;                  }              }              // includes #              if (checkSegment.indexOf("#") > -1) {                  // take first #                  numberSplit = checkSegment.split("#");                  if (numberSplit.length != 2) {                        continue;                  } else {                      n = numberSplit[0];                      if (n && !(isNaN(n)))                          numbers.push(n);                      else if (numberSplit[0] == "0")                          numbers.push(n);                      continue;                 }             }      // includes -              if (checkSegment.indexOf("-") > 0) {                  // take both #                  numberSplit = checkSegment.split("-");                  if (numberSplit.length != 2) {                       continue;                  } else if (Number(numberSplit[0]) > Number(numberSplit[1])) {                      continue;                  } else {                      n = numberSplit[0];                      if (n && !(isNaN(n)))                          numbers.push(n);                      else if (numberSplit[0] == "0")                          numbers.push(n);                      n = numberSplit[1];                      if (n && !(isNaN(n)))                          numbers.push(n);                      else if (numberSplit[1] == "0")                          numbers.push(n);                      continue;                  }              }          }          // lastly, check that all the found numbers are in range          i = -1;          l = numbers.length;          if (l == 0)              return false;          while (++i < l) {              // alert(numbers[i]);              if (numbers[i] < range[0] || numbers[i] > range[1]) {                  return false;              }          }          return true;      }

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