Java正则表达式示例

String.matches(regex)

 检测字符串是否为数字
 

package com.java265.regex;
import java.util.Arrays;
import java.util.list;
public class JavaRegEx1 {
    public static void main(String[] args) {
        List<String> numbers = Arrays.asList("88", "99", "java", "666", "8nwwe98");
 
        for (String number : numbers) {
		
            if (number.matches("\\d+")) {
                System.out.println(number);		//88,99,666
            }
        }
 
        // Java 8 stream example
        numbers.stream()
                .filter(x -> x.matches("\\d+"))
                .forEach(System.out::println);
 
    }
}

String.replaceAll(正则表达式,替换)

将所有数字替换为#

package com.java265.regex;
import java.util.Arrays;
import java.util.List;
public class JavaRegEx2 {
    public static void main(String[] args) {
        List<String> numbers = Arrays.asList("88", "99", "java", "666", "8nwwe98");
 
        for (String number : numbers) {
            System.out.println(number.replaceAll("\\d", "#"));
        }
 
        // Java 8 stream example
        numbers.stream()
                .map(x -> x.replaceAll("\\d", "#"))
                .forEach(System.out::println);
    }
}

模式和匹配器

package com.java265.regex;
import java.util.Arrays;
import java.util.List;
import java.util.regex.Matcher;
import java.util.regex.Pattern;
 
public class JavaRegEx3 {
    public static void main(String[] args) {
        List<String> numbers = Arrays.asList("88", "99", "java", "666", "8nwwe98");
        Pattern pattern = Pattern.compile("\\d+");
        for (String number : numbers) {
            Matcher matcher = pattern.matcher(number);
            while (matcher.find()) {
                System.out.println(matcher.group(0));
            }
        }
	}
}