英文:
Regex Validation for "ASSOC123" in Java
问题
我有一个任务，需要检查一个以大写的 "ASSOC" 开头，后面跟着3位数字的ID。我是Java方面的新手，还在学习正则表达式，所以任何帮助都将受之以欢迎！
英文:
I have a task to check an ID that must start with "ASSOC" in uppercase followed by 3 digits. I am a newbie in Java and still learning regex so any help would be welcome!
答案1
得分: 0
以下正则表达式匹配任何与所需模式匹配的字符串：ASSOC[0-9]{3}。
如果您还想从匹配中提取三位数字ID，作为所谓的正则表达式组，表达式必须如下所示：ASSOC([0-9]{3})。
[0-9] 在这里表示我们期望一个数字字符（数字）从0到9。花括号还表示正好3个数字，因此期望一个三位数。
在Regex101上，您还可以使用此正则表达式验证不同的输入。此外，详细解释了正则表达式。
- 示例1：https://regex101.com/r/zEN9Gt/1
- 示例2：https://regex101.com/r/zEN9Gt/2
在Java中，您可以按以下方式测试这个正则表达式：
import java.util.regex.Matcher;
import java.util.regex.Pattern;
final String regex = "ASSOC([0-9]{3})";
final Pattern pattern = Pattern.compile(regex);
final Matcher matcher1 = pattern.matcher("ASSOC123");
final Matcher matcher2 = pattern.matcher("Assoc123");
if(matcher1.find()) {
System.out.println(matcher1.group(1));
// 由于"ASSOC123"是正则表达式的有效输入，
// matcher1.find() 为true，我们可以输出三位数（注意：是第1组！）。
// 第0组将是找到的整个表达式，因此是"ASSOC123"。
}
if(matcher2.find()) {
// 由于"Assoc123"不匹配正则表达式，matcher2.find() 为false
}
英文:
The following regular expression matches any string that matches the pattern you want: ASSOC[0-9]{3}.
If you also want to extract the 3-digit ID as a so-called regex-group from the match, the expression must be as follows: ASSOC([0-9]{3}).
The [0-9] says here, that we expect a number-character (digit) of 0-9. The curly brackets also express that exactly 3 digits, therefore a 3-digit number is expected.
On Regex101 you also have the possibility to validate different inputs with this regex. Furthermore the regular expression is explained in detail.
- Example 1: https://regex101.com/r/zEN9Gt/1
- Example 2: https://regex101.com/r/zEN9Gt/2
In Java you could test this as follows:
import java.util.regex.Matcher;
import java.util.regex.Pattern;
final String regex = "ASSOC([0-9]{3})";
final Pattern pattern = Pattern.compile(regex);
final Matcher matcher1 = pattern.matcher("ASSOC123");
final Matcher matcher2 = pattern.matcher("Assoc123");
if(matcher1.find()) {
System.out.println(matcher1.group(1));
// Since ASSOC123 is a valid input for the regular expression,
// matcher1.find() is true and we can output the 3 digit number (attention: group 1!).
// Group 0 would be the entire expression found, hence "ASSOC123".
}
if(matcher2.find()) {
// Since "Assoc123" does not match the regular expression, matcher2.find() is false
}
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