StringUtils判断字符串是否为空

<!-- 判断字符串是否为空 -->
<dependency>
    <groupId>org.apache.commons</groupId>
    <artifactId>commons-lang3</artifactId>
    <version>3.8.1</version>
</dependency>

import org.apache.commons.lang3.StringUtils;
public class Action {
    public static void main(String[] args) {
        String a=null;
        String b="";
        if(StringUtils.isEmpty(a)){
            System.out.println("a空");
        }
        if(StringUtils.isEmpty(b)){
            System.out.println("b空");
        }
    }
}