/**
* jetbrick-template
* http://subchen.github.io/jetbrick-template/
*
* Copyright 2010-2014 Guoqiang Chen. All rights reserved.
* Email: subchen@gmail.com
*
* Licensed under the Apache License, Version 2.0 (the "License");
* you may not use this file except in compliance with the License.
* You may obtain a copy of the License at
*
* http://www.apache.org/licenses/LICENSE-2.0
*
* Unless required by applicable law or agreed to in writing, software
* distributed under the License is distributed on an "AS IS" BASIS,
* WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
* See the License for the specific language governing permissions and
* limitations under the License.
*/
package jetbrick.template.runtime;
import java.io.IOException;
import java.util.Map;
import javax.servlet.ServletContext;
import javax.servlet.http.HttpSession;
import jetbrick.template.JetContext;
import jetbrick.template.JetTemplate;
import jetbrick.template.utils.TimedSizeCache;
import jetbrick.template.web.JetWebContext;
/**
* 系统自带的 Tag
*/
public final class JetTags {
/**
* 实现 layout 的 tag, 将内容插入到 ${bodyContent}
*
* @param ctx Tag 上下文对象
* @param file layout 模板路径
*
* @since 1.1.0
*/
public static void layout(JetTagContext ctx, String file) {
layout(ctx, file, null);
}
/**
* 实现 layout 的 tag, 将内容插入到 ${bodyContent}，支持传递参数
*
* @param ctx Tag 上下文对象
* @param file layout 模板路径
*
* @since 1.1.1
*/
public static void layout(JetTagContext ctx, String file, Map<String, Object> parameters) {
JetContext context;
if (parameters == null || parameters.size() == 0) {
context = ctx.getContext();
} else {
context = new JetContext(ctx.getContext(), parameters);
}
String bodyContent = ctx.getBodyContent();
ctx.getContext().put("bodyContent", bodyContent);
file = ctx.getPageContext().getAbsolutionName(file);
JetTemplate template = ctx.getEngine().getTemplate(file);
template.render(context, ctx.getWriter());
}
/**
* 将一个 Block 的内容保存到一个 JetContext 变量中。
*
* @param ctx Tag 上下文对象
* @param name 保存到 JetContext 的变量名
*
* @since 1.1.1
*/
public static void block(JetTagContext ctx, String name) {
String bodyContent = ctx.getBodyContent();
ctx.getContext().put(name, bodyContent);
}
/**
* 如果不存在指定的 JetContext 变量，那么输出 default_block 块内容，否则输出指定的 JetContext 变量。
*
* @param ctx Tag 上下文对象
* @param name JetContext 的变量名
*
* @since 1.1.2
*/
public static void default_block(JetTagContext ctx, String name) throws IOException {
Object value = ctx.getContext().get(name);
if (value == null) {
ctx.writeBodyContent();
} else {
ctx.getWriter().print(value);
}
}
/**
* ServletContext 级别的 cache.
*
* @param ctx Tag 上下文对象
* @param name cache 名称
* @param timeout 超时时间，单位秒
*
* @since 1.2.0
*/
public static void application_cache(JetTagContext ctx, String name, long timeout) throws IOException {
ServletContext sc = (ServletContext) ctx.getContext().get(JetWebContext.SERVLET_CONTEXT);
TimedSizeCache cache = (TimedSizeCache) sc.getAttribute(TimedSizeCache.CACHE_KEY);
if (cache == null) {
cache = new TimedSizeCache(128);
sc.setAttribute(TimedSizeCache.CACHE_KEY, cache);
}
Object value = cache.get(name);
if (value == null) {
value = ctx.getBodyContent();
cache.put(name, value, timeout * 1000);
}
ctx.getWriter().print(value);
}
/**
* HttpSession 级别的 cache.
*
* @param ctx Tag 上下文对象
* @param name cache 名称
* @param timeout 超时时间，单位秒
*
* @since 1.2.0
*/
public static void session_cache(JetTagContext ctx, String name, long timeout) throws IOException {
HttpSession session = (HttpSession) ctx.getContext().get(JetWebContext.SESSION);
TimedSizeCache cache = (TimedSizeCache) session.getAttribute(TimedSizeCache.CACHE_KEY);
if (cache == null) {
cache = new TimedSizeCache(128);
session.setAttribute(TimedSizeCache.CACHE_KEY, cache);
}
Object value = cache.get(name);
if (value == null) {
value = ctx.getBodyContent();
cache.put(name, value, timeout * 1000);
}
ctx.getWriter().print(value);
}
}