public static File writeUtf8String(String content, File file) throws IORuntimeException {
		return writeString(content, file, CharsetUtil.CHARSET_UTF_8);
	}
public static File writeUtf8String ( String content , File file ) throws IORuntimeException { return writeString ( content , file , CharsetUtil . CHARSET_UTF_8 ) ; }
将String写入文件，覆盖模式，字符集为UTF-8

@param content 写入的内容
@param file 文件
@return 写入的文件
@throws IORuntimeException IO异常