Java下变量大小写驼峰、大小写下划线、大小写连线转换

<dependency>
     <groupId>com.google.guava</groupId>
     <artifactId>guava</artifactId>
     <version>25.1-jre</version>
 </dependency>

public static void main(String[] args) {
        // 变量小写连接线转小写驼峰
        System.out.println(CaseFormat.LOWER_HYPHEN.to(CaseFormat.LOWER_CAMEL, "user-name"));//userName
        // 变量小写连接线转小写下划线
        System.out.println(CaseFormat.LOWER_HYPHEN.to(CaseFormat.LOWER_UNDERSCORE, "user-name"));//user_name
        // 变量小写下划线转小写驼峰
        System.out.println(CaseFormat.LOWER_UNDERSCORE.to(CaseFormat.LOWER_CAMEL, "user_name"));//userName
        // 变量下划线转大写驼峰
        System.out.println(CaseFormat.UPPER_UNDERSCORE.to(CaseFormat.UPPER_CAMEL, "user_name"));//UserName
        // 变量小写驼峰转大写驼峰
        System.out.println(CaseFormat.LOWER_CAMEL.to(CaseFormat.UPPER_CAMEL, "userName"));//UserName
        // 变量小写驼峰转小写下划线
        System.out.println(CaseFormat.LOWER_CAMEL.to(CaseFormat.LOWER_UNDERSCORE, "userName"));//user_name
        // 变量小写驼峰转小写下划线
        System.out.println(CaseFormat.LOWER_CAMEL.to(CaseFormat.LOWER_UNDERSCORE, "UserName"));//user_name
        // 变量小写驼峰转小写连接线
        System.out.println(CaseFormat.LOWER_CAMEL.to(CaseFormat.LOWER_HYPHEN, "userName"));//user-name
    }