public static String getPackage(Class<?> clazz) {
		if (clazz == null) {
			return StrUtil.EMPTY;
		}
		final String className = clazz.getName();
		int packageEndIndex = className.lastIndexOf(StrUtil.DOT);
		if (packageEndIndex == -1) {
			return StrUtil.EMPTY;
		}
		return className.substring(0, packageEndIndex);
	}
public static String getPackage ( Class < ? > clazz ) { if ( clazz == null ) { return StrUtil . EMPTY ; } final String className = clazz . getName ( ) ; int packageEndIndex = className . lastIndexOf ( StrUtil . DOT ) ; if ( packageEndIndex == - 1 ) { return StrUtil . EMPTY ; } return className . substring ( 0 , packageEndIndex ) ; }
获得给定类所在包的名称<br>
例如：<br>
com.xiaoleilu.hutool.util.ClassUtil =》 com.xiaoleilu.hutool.util

@param clazz 类
@return 包名