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0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 MatchAllCharacters {
public static void main( String args[] ) {
String regex = "(.*)?(\\d+)";
Scanner sc = new Scanner(System.in);
System.out.println("Enter 5 input strings: ");
String input[] = new String[5];
for (int i=0; i<5; i++) {
input[i] = sc.nextLine();
}
//创建一个Pattern对象
Pattern p = Pattern.compile(regex);
System.out.println("Strings containing digits: ");
for(int i=0; i<5;i++) {
//创建一个Matcher对象
Matcher m = p.matcher(input[i]);
if(m.matches()) {
System.out.println(m.group());
}
}
}
}输出结果
test data hello how are you 335 welcome to Nhooo Strings containing digits: sample text 1 hello how are you 335