Setting Up the CLASSPATH
This topic describes how Geode processes set their CLASSPATH.
To simplify CLASSPATH environment settings, Geode has organized all application libraries required by Geode processes into
*-dependencies.jar files. All dependency JAR files are located in the
path_to_product/lib directory. When starting a server or locator process using
gfsh, the required application JAR files are automatically loaded into the process’s CLASSPATH for you.
To embed Geode in your application, add
path_to_product/lib/geode-dependencies.jar to your CLASSPATH.
The following table lists the dependency JAR files associated with various Geode processes:
|Geode Process||Associated JAR Files|
|server and locator||geode-dependencies.jar
Use this library for all standalone or embedded Geode processes (including Java clients) that host cache data.
Modifying the CLASSPATH in gfsh-Managed Processes
There are two options for updating the CLASSPATH of Geode server and locator processes that are started on the gfsh command line.
Option 1: Specify the
--classpath parameter upon process startup. For example, to modify the CLASSPATH of a locator:
gfsh> start locator --name=locator1 --classpath=/path/to/applications/classes.jar
And to modify the CLASSPATH of a server:
gfsh> start server --name=server1 --classpath=/path/to/applications/classes.jar
Application classes supplied as arguments to the
--classpath option are prepended to the server or locator’s CLASSPATH, beginning in second position. The first entry in the CLASSPATH is reserved for the core Geode jar file, for security reasons.
Option 2: Define the CLASSPATH environment variable in your OS environment. Then, specify the
--include-system-classpath parameter upon process startup. For example:
gfsh> start locator --name=locator1 --include-system-classpath=true
The same can also be done for server processes:
gfsh> start server --name=server1 --include-system-classpath=true
This option appends the contents of the system CLASSPATH environment variable to the locator or server’s CLASSPATH upon startup. Specifying this option without a value sets it to true.
Setting the CLASSPATH for Applications and Standalone Java Processes
If you are starting a Geode process programmatically (standalone or embedded), we recommend that you specify the CLASSPATH upon program execution using the
java -classpath or
java -cp command-line option. This method is preferred to setting the CLASSPATH as an environment variable since it allows you to set the value individually for each application without affecting other applications and without other applications modifying its value.
For example, to start up a Geode locator process using the LocatorLauncher API, you can execute the following on the command line:
prompt# java -cp "path_to_product/lib/geode-dependencies.jar" org.apache.geode.distributed.LocatorLauncher start locator1 <locator-launcher-options>
To start up a Geode server process using the ServerLauncher API:
prompt# java -cp "path_to_product/lib/geode-dependencies.jar:/path/to/your/applications/classes.jar" org.apache.geode.distributed.ServerLauncher start server1 <server-launcher-options>
Note that in addition to the
*-dependencies.jar file associated with the process, you must also specify any custom application JARs that you wish to access in your Geode process. For example, if you are planning on using a customized compressor on your regions, you should specify the application JAR that contains the compressor application you wish to use.
To start up an application with an embedded cache:
java -cp "path_to_product/lib/geode-dependencies.jar:/path/to/your/applications/classes.jar" com.mycompany.package.ApplicationWithEmbeddedCache
Another method for updating the CLASSPATH of a server process with your own applications is to use the
gfsh deploy command. Deploying application JAR files will automatically update the CLASSPATH of all members that are targeted for deployment. See Deploying Application JARs to Apache Geode Members for more details.