OpenCms Documentation

Flex cache settings

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In OpenCms since: 6.0 Valid for OpenCms: 12.0

The flex cache caches the HTML output of JSPs in the memory (RAM) of your server. We demonstrate different variants of caching. Therefore, we include two JSPs into each other, both showing the current time. Playing with the cache directives set on the JSPs, the time is refreshed differently. Futhermore, we show how navigation should be cached.

The result

The examples will only work online since caching is disabled offline (in the default flex cache configuration)!

Below you'll find three examples. Each example is a dynamic function, whose provider JSP includes another JSP. Reload this page in the online project and see how the time changes (or not). Also note that the navigation renders differently on different pages. For each page one version is cached.


File: include-example1.jsp

The Date is Sat Oct 23 09:49:16 CEST 2021

Cache properties: never

File: include-target1.jsp

The Date is Sat Oct 23 09:49:16 CEST 2021

Cache properties: timeout=1

File: include-example2.jsp

The Date is Sat Oct 16 09:05:46 CEST 2021

Cache properties: always

File: include-target2.jsp

The Date is Sat Oct 23 09:49:16 CEST 2021

Cache properties: never


Example resources and the interesting spots

The interesting parts here are not the JSPs themselves, but the properties set there.

If you are offline, open the workplace's explorer view in the root site and go to the following folder to see the resources used in the examples:

In this folder, you'll find all resources that are used. Right-click on a resource and choose "Properties" in the context menu to view the properties. In the "Individual properties" tab you'll find the cache settings.

To see that the JSP's output is really cached, go to the workplace's administration view and choose "Cache Administration". In the frame "Browse cache contents", click "Flex Cache". There you'll find a listing of all flex-cache entries. Click on "Variations" (upper-right corner of the listing) to see the different variations that are cached.

To find the cached variations of the JSP outputs from the above example, first view it online.

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