用Java解释正则表达式“ \ s”元字符
子表达式/元字符“\s”与空白等效。
例子1
import java.util.regex.Matcher;
import java.util.regex.Pattern;
public class RegexExample {
public static void main( String args[] ) {
String regex = "\\s";
String input = "您好，欢迎来到Nhooo！";
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: 7
例子2
下面的示例读取一个字符串，并删除它们之间的所有多余空格。
import java.util.Scanner;
import java.util.regex.Matcher;
import java.util.regex.Pattern;
public class Example {
public static void main(String args[]) {
//从用户读取字符串
System.out.println("Enter a String");
Scanner sc = new Scanner(System.in);
String input = sc.nextLine();
//正则表达式以匹配空格（一个或多个）
String regex = "\\s+";
//编译正则表达式
Pattern pattern = Pattern.compile(regex);
//检索匹配器对象
Matcher matcher = pattern.matcher(input);
//用单个空格替换所有空格字符
String result = matcher.replaceAll(" ");
System.out.print("Text after removing unwanted spaces: \n"+result);
}
}输出结果
Enter a String hello this is a sample text with irregular spaces Text after removing unwanted spaces: hello this is a sample text with irregular spaces