Java中的正则表达式re +元字符
子表达式/元字符“re+”与前面的表达式的一个或多个匹配。
例子1
import java.util.regex.Matcher;
import java.util.regex.Pattern;
public class RegexExample {
public static void main( String args[] ) {
String regex = "aabc+";
String input = "aabcabcaabcabbcaabcbcaabc";
Pattern p = Pattern.compile(regex);
Matcher m = p.matcher(input);
int count = 0;
while(m.find()) {
count++;
}
System.out.println("Number of matches: "+count);
}
}输出结果
Number of matches: 4
例子2
import java.util.Scanner;
import java.util.regex.Matcher;
import java.util.regex.Pattern;
public class Test {
public static void main( String args[] ) {
String regex = "[0-9]+";
Scanner sc = new Scanner(System.in);
System.out.println("Enter an input string: ");
String input = sc.nextLine();
//Creating a Pattern object
Pattern p = Pattern.compile(regex);
//Creating a Matcher object
Matcher m = p.matcher(input);
if(m.find()) {
System.out.println("Given input contains digits");
} else {
System.out.println("Given input doesn't contain digits");
}
}
}输出1
Enter an input string: sample text Given input doesn't contain digits
输出2
Enter an input string: sample data 464 Given input contains digits