Java regex matching multiple digit sequences separated with colon

Question

I have a string that must have the given format: at least ddd:dd or ddd:dd,ddd:dd or ddd:dd,ddd:dd,ddd:dd Seeing the JavaDoc, I use this pattern: "^[\\d{3}:\\d{2}]+[,\\d{3}:\\d{2}]*$" Code: myString.matches("^[\\d{3}:\\d{2}]+[,\\d{3}:\\d{2}]{0,2}$") It does not work, but I see no mistake.

Answer 1

关于你的正则表达式有一点需要注意的是它在字符类（[...]中存在一个关键问题，我们在其中定义了我们想要匹配或不想匹配的符号的字符或范围）而不是组（ (...)我们只使用我们需要匹配的字符序列，或者使用替代字符。 Here you can see what your regex actually matches：

我确信{3}: a single character in the list {3}: literally确实是你不想要的。

如果d代表任何数字，则需要使用类似

的内容

String pattern = "\\d{3}:\\d{2}(?:,\\d{3}:\\d{2})*";
Pattern r = Pattern.compile(pattern);
Matcher m = r.matcher("111:11,222:22,222:22");

while (m.find()) {
       System.out.println(m.group());   
}

请参阅IDEONE demo

以下是an example with matches：

String pattern = "\\d{3}:\\d{2}(?:,\\d{3}:\\d{2})*";
System.out.println("222:22,222:22".matches(pattern));
System.out.println("111:11,222:22,222:22".matches(pattern));

Answer 2

Problems with your regex you are using \d which matches a digit You are using [] which are used for defining ranges Try ^(d{3}:d{2})(,d{3}:d{2}){0,2}$

Answer 3

• [xyz] - []表示它与列出的任何一个字符相匹配，因此x或y或z。< / LI>
• (xyz)是一个群组，会匹配字符x，然后是y，然后是z。

你想要这个正则表达式：

"^(\\d{3}:\\d{2}($|,(?!$)))+$"

• ^匹配字符串的开头。
• \\d{3}:\\d{2}符合您的模式;
紧接着
• ($|,(?!$))将匹配字符串结尾$或逗号,，后面没有字符串结尾(?!$)
前面两个表达式的
• (...)+$将匹配您的一个或多个模式（如果有多个，则必须用逗号分隔），然后是字符串结尾。