java 字符串—数字常用处理

 // 判断一个字符串是否都为数字
	public boolean isDigit(String strNum) {
		return strNum.matches("[0-9]{1,}");
	}

	// 判断一个字符串是否都为数字
	public boolean isDigit(String strNum) {
		Pattern pattern = Pattern.compile("[0-9]{1,}");
		Matcher matcher = pattern.matcher((CharSequence) strNum);
		return matcher.matches();
	}

    //截取数字
    public String getNumbers(String content) {
        Pattern pattern = Pattern.compile("\d+");
        Matcher matcher = pattern.matcher(content);
        while (matcher.find()) {
            return matcher.group(0);
        }
        return "";
    }

	// 截取非数字
	public String splitNotNumber(String content) {
		Pattern pattern = Pattern.compile("\D+");
		Matcher matcher = pattern.matcher(content);
		while (matcher.find()) {
			return matcher.group(0);
		}
		return "";
	}

  含小数点

public static boolean isNum(String str){
        return str.matches("^[-+]?(([0-9]+)([.]([0-9]+))?|([.]([0-9]+))?)$");
    }

取连续数字

private static Set<Integer> getNumsFromStr(String str) {

  String[] ary = str.replaceAll("[^\d]", " ").split("\s+");
  
  Set<Integer> set = new TreeSet<Integer>();
  
  for(String num: ary){
   if(!num.trim().equals("")){
    set.add(new Integer(num.trim()));
   }
  }
  
  return set;
 }
原文地址:https://www.cnblogs.com/sanxinglan/p/3286432.html