java JSP trimDirectiveWhitespaces
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JSP trimDirectiveWhitespaces
提问by NinaNa
I am testing several ways to improve and reduce my response size, network traffic, and load time. One of the things I thought of using is the trimDirectiveWhitespaces element. I placed it in the page directive:
我正在测试几种方法来改进和减少我的响应大小、网络流量和加载时间。我想到使用的一件事是trimDirectiveWhitespaces 元素。我把它放在页面指令中：
<%@ page contentType="text/html;charset=UTF-8" language="java" trimDirectiveWhitespaces="true"%>
I added some empty new lines and didn't see any change in my response or when i view source of the document, new lines were there.
我添加了一些空的新行，但在我的响应中没有看到任何变化，或者当我查看文档源时，出现了新行。
What is the correct usage of this and what am I doing wrong?
这个的正确用法是什么，我做错了什么？
回答by David Bala?ic
trimDirectiveWhitespacesonly removes empty lines around JSP tags and leaves other empty lines as they are.
trimDirectiveWhitespaces仅删除 JSP 标记周围的空行，而其他空行保持原样。
Example:
例子：
<% page pageEncoding="UTF-8"%>X
<%@ taglib prefix="c" uri="http://java.sun.com/jsp/jstl/core" %>X
<html>
<head>
This will become:
这将变成：
X
X
<html>
<head>
(note I added Xto mark end-of-line for this example, so it is more obvious and stackoverflow wont trim them out)
（注意我X在这个例子中添加了标记行尾，所以它更明显并且stackoverflow不会修剪它们）
If trimDirectiveWhitespaces="true"is added to the pagedirective, the output becomes:
如果trimDirectiveWhitespaces="true"添加到page指令中，输出变为：
<html>
<head>
The first two empty lines are removed, but the next two (between the htmland headtags) are preserved.
前两个空行被删除，但接下来的两个（在html和head标签之间）被保留。
回答by SamDJava
You can place the following configuration for trim-directive-whitespacesin web.xmlas well:
你可以把下面的配置trim-directive-whitespaces中web.xml还有：
<web-app xmlns=...>
(...)
<jsp-config>
<jsp-property-group>
<url-pattern>*.jsp</url-pattern>
<trim-directive-whitespaces>true</trim-directive-whitespaces>
</jsp-property-group>
</jsp-config>
(...)
</web-app>
