SiteMesh3整合SpringMVC+FreeMarker

SiteMesh3配置

SiteMesh3文档 http://wiki.sitemesh.org/wiki/pages/viewpage.action?pageId=1081348

重新搭建项目偶然发现SiteMesh有了新版本SiteMesh3，本着用新不用旧原则果断升级，多少遇了点坑，顺便记录下

SiteMesh3配置

添加maven依赖

<dependency>

    <groupId>org.sitemesh</groupId>

    <artifactId>sitemesh</artifactId>

    <version>3.0.1</version>

</dependency>

添加filter

在web.xml中添加filter

<filter>

    <filter-name>sitemesh</filter-name>

    <filter-class>org.sitemesh.config.ConfigurableSiteMeshFilter</filter-class>

</filter>

<filter-mapping>

    <filter-name>sitemesh</filter-name>

    <url-pattern>/*</url-pattern>

</filter-mapping>

配置servlet

<servlet-mapping>

    <servlet-name>default</servlet-name>

    <url-pattern>*.ftl</url-pattern>

</servlet-mapping>

添加sitemesh配置文件

添加配置文件 sitemesh3.xml
默认配置文件路径为：/WEB-INF/sitemesh3.xml

sitemesh3.xml

<sitemesh>

    <!--

    By default, SiteMesh will only intercept responses that set the Content-Type HTTP header to text/html

    This can be altered to allow SiteMesh to intercept responses for other types.

    默认 SiteMesh 只对HTTP响应头中Content-Type为 text/html 的类型进行拦截和装饰，若需要处理其它mime类型需要自行添加配置

    -->

    <mime-type>text/html</mime-type>

    <!--

    Map default decorator. This shall be applied to all paths if no other paths match.

    配置装饰器，仅设置decorator参数时表示为默认的装饰器，当没有任何路径被匹配时会使用默认装饰器装配

     -->

    <mapping decorator="/WEB-INF/decorators/decorator.ftl"/>

    <!--对不同的路径指定特定的装饰器-->

    <!--<mapping path="/admin/*" decorator="/WEB-INF/decorators/admin-decorator.ftl"/>-->

    <!--

    Alternative convention. This is more verbose but allows multiple decorators to be applied to a single path.

    对同一路径可以同时使用多个装饰器

    -->

    <mapping>

        <path>/category/*</path>

        <decorator>/WEB-INF/decorators/common-decorator.ftl</decorator>

        <decorator>/WEB-INF/decorators/menu-decorator.ftl</decorator>

        <decorator>/WEB-INF/decorators/category-decorator.ftl</decorator>

    </mapping>

    <!--

    Exclude path from decoration.

    排除路径，只需将exclue设置为true即可

    -->

    <mapping path="/static/*" exclue="true"/>

    <!--

    An advanced feature of SiteMesh is the ability to define custom rules that manipulate tags on a page.

    These are classes that implement org.sitemesh.content.tagrules.TagRuleBundle.

    默认SiteMesh仅支持title、head、meta、body等tag,可以自定义tag，实现TagRuleBundle接口即可

    -->

    <content-processor>

        <tag-rule-bundle class="com.sankuai.shangchao.util.HtmlTagRuleBundle"/>

    </content-processor>

</sitemesh>

修改配置文件路径
默认配置文件路径为：/WEB-INF/sitemesh3.xml 若需要修改配置文件路径需要在filter里配置configFile参数

<filter>

    <filter-name>sitemesh</filter-name>

    <filter-class>org.sitemesh.config.ConfigurableSiteMeshFilter</filter-class>

    <init-param>

        <param-name>configFile</param-name>

        <param-value>/WEB-INF/sitemesh3.xml</param-value>

    </init-param>

</filter>

自定义tag

HtmlTagRuleBundle.java

import org.sitemesh.SiteMeshContext;

import org.sitemesh.content.ContentProperty;

import org.sitemesh.content.tagrules.TagRuleBundle;

import org.sitemesh.content.tagrules.html.ExportTagToContentRule;

import org.sitemesh.tagprocessor.State;

/**

 * Description: FootTagRuleBundle

 * Author: liuzhao

 * Create: 2015-08-22 09:21

 */

public class HtmlTagRuleBundle implements TagRuleBundle {

    @Override

    public void install(State defaultState, ContentProperty contentProperty, SiteMeshContext siteMeshContext) {

        defaultState.addRule("foot", new ExportTagToContentRule(siteMeshContext, contentProperty.getChild("foot"), false));

    }

    @Override

    public void cleanUp(State defaultState, ContentProperty contentProperty, SiteMeshContext siteMeshContext) {

    }

}

decorator示例

decorator配置页面布局layout，对应的tag会被进行装饰替换

decorator.ftl

<!DOCTYPE html>

<html>

<head>

<title>

<sitemesh:write property="title"/>

</title>

<sitemesh:write property='head'/>

</head>

<body>

<h1>啦拉拉，我是卖报的小行家</h1>

<sitemesh:write property='body'/>

<sitemesh:write property="foot"/>

</body>

</html>

SpringMVC、FreeMarker配置（404问题处理）

sitemesh3是完全独立的，不和任何框架进行偶合，因此SpringMVC、FreeMarker配置完全不需要考虑sitemesh3的兼容问题
在加载装饰器的时候，会出现404问题，可能的原因是找不到ftl文件的解析器，所以需要配置下ftl使用默认的Servlet解析，在web.xml中添加如下配置

<servlet-mapping>

<servlet-name>default</servlet-name>

<url-pattern>*.ftl</url-pattern>

</servlet-mapping>

decorate源码

@Override

protected boolean postProcess(String contentType, CharBuffer buffer,

HttpServletRequest request, HttpServletResponse response,

ResponseMetaData metaData)

throws IOException, ServletException {

WebAppContext context = createContext(contentType, request, response, metaData);

Content content = contentProcessor.build(buffer, context);

if (content == null) {

return false;

}

String[] decoratorPaths = decoratorSelector.selectDecoratorPaths(content, context);

//遍历装饰器进行装饰

for (String decoratorPath : decoratorPaths) {

content = context.decorate(decoratorPath, content);

}

if (content == null) {

return false;

}

try {

content.getData().writeValueTo(response.getWriter());

} catch (IllegalStateException ise) { // If getOutputStream() has already been called

content.getData().writeValueTo(new PrintStream(response.getOutputStream()));

}

return true;

}

public Content decorate(String decoratorName, Content content) throws IOException {

if (decoratorName == null) {

return null;

}

class CharBufferWriter extends CharArrayWriter {

public CharBuffer toCharBuffer() {

return CharBuffer.wrap(this.buf, 0, this.count);

}

CharBufferWriter out = new CharBufferWriter();

decorate(decoratorName, content, out);

CharBuffer decorated = out.toCharBuffer();

Content lastContent = currentContent;

currentContent = content;

try {

return contentProcessor.build(decorated, this);

} finally {

currentContent = lastContent;

}

@Override

protected void decorate(String decoratorPath, Content content, Writer out) throws IOException {

HttpServletRequest filterableRequest = new HttpServletRequestFilterable(request);

// Wrap response so output gets buffered.

HttpServletResponseBuffer responseBuffer = new HttpServletResponseBuffer(response, metaData, new BasicSelector(new PathMapper<Boolean>(), includeErrorPages) {

@Override

public boolean shouldBufferForContentType(String contentType, String mimeType, String encoding) {

return true; // We know we should buffer.

}

});

responseBuffer.setContentType(response.getContentType()); // Trigger buffering.

// It's possible that this is reentrant, so we need to take a copy

// of additional request attributes so we can restore them afterwards.

Object oldContent = request.getAttribute(CONTENT_KEY);

Object oldContext = request.getAttribute(CONTEXT_KEY);

request.setAttribute(CONTENT_KEY, content);

request.setAttribute(CONTEXT_KEY, this);

try {

// Main dispatch.

dispatch(filterableRequest, responseBuffer, decoratorPath);

// Write out the buffered output.

CharBuffer buffer = responseBuffer.getBuffer();

out.append(buffer);

} catch (ServletException e) {

//noinspection ThrowableInstanceNeverThrown

throw (IOException) new IOException("Could not dispatch to decorator").initCause(e);

} finally {

// Restore previous state.

request.setAttribute(CONTENT_KEY, oldContent);

request.setAttribute(CONTEXT_KEY, oldContext);

}

protected void dispatch(HttpServletRequest request, HttpServletResponse response, String path)

throws ServletException, IOException {

//这里调用加载文件会出现404错误 /WEB-INF/decorators/decorator.ftl

RequestDispatcher dispatcher = servletContext.getRequestDispatcher(path);

if (dispatcher == null) {

throw new ServletException("Not found: " + path);

}

dispatcher.forward(request, response);

}