xdocs/UpgradingFrom2x.xml (72 lines of code) (raw):
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<document>
<properties>
<title>Upgrading from JCS 2.x to 3.0</title>
<author email="tv@apache.org">Thomas Vandahl</author>
</properties>
<body>
<section name="Upgrading from JCS 2.x to 3.0">
<p>
This document lists a number of things that changed in Commons JCS
3.0.
</p>
<subsection name="Minimum Java Requirements">
<p>
JCS 3.x requires Java 8 to run. It was tested successfully with JDK 14.
</p>
</subsection>
<subsection name="Package Names and Maven Coordinates">
<p>
The Apache Commons project requires a change of the package names
and Maven coordinates on a major release.
So in all your code replace
<source><![CDATA[
import org.apache.commons.jcs.*;
]]></source>
with
<source><![CDATA[
import org.apache.commons.jcs3.*;
]]></source>
The Maven coordinates change from
<source><![CDATA[
<dependency>
<groupId>org.apache.commons.jcs</groupId>
<artifactId>commons-jcs-core</artifactId>
<version>2.2.1</version>
</dependency>
]]></source>
to
<source><![CDATA[
<dependency>
<groupId>org.apache.commons</groupId>
<artifactId>commons-jcs3-core</artifactId>
<version>3.0</version>
</dependency>
]]></source>
</p>
</subsection>
<subsection name="Adjusting the Configuration">
<p>
Here again, change all package names in configuration entries
from e.g.
<source><![CDATA[
jcs.default.cacheattributes=org.apache.commons.jcs.engine.CompositeCacheAttributes
]]></source>
to
<source><![CDATA[
jcs.default.cacheattributes=org.apache.commons.jcs3.engine.CompositeCacheAttributes
]]></source>
</p>
</subsection>
<subsection name="Logging Abstraction">
<p>
JCS 3.0 uses its own log abstraction layer. As newer and better
log systems become available, JCS is no longer limited to
commons-logging. As a result, JCS now uses java.util.logging as
default and does not depend on commons-logging anymore.
</p>
<p>
Optionally, JCS can use Log4j2 as a log system. You can activate
it by providing log4j-core as a dependency, a log configuration
such as log4j2.xml and a system property
<source><![CDATA[
-Djcs.logSystem=log4j2
]]></source>
As log initialization occurs very early in the startup process,
be sure to add this property before accessing any of JCS' classes.
</p>
<p>
JCS uses the Java SPI mechanism to find its log systems. If you want
to roll your own, you will need to implement a
<code>org.apache.commons.jcs.log.Log</code> object and a
<code>org.apache.commons.jcs.log.LogFactory</code>
and provide the implementation class in a text file
<code>META-INF/services/org.apache.commons.jcs.log.LogFactory</code>
in your code. Choose a name for your log system and activate it via
the system property as described above.
</p>
</subsection>
</section>
</body>
</document>