This assumes you have installed the IBM Application Client package.

IBM Application Client is similar to IBM WebSphere Application Server. Just like WebSphere, IBM Application Client is a package that you will install using IBMs Installation Manager. However, unlike WebSphere, the Application Client package is not a full blown Application Server. There is no web browser interface for the Application Client, meaning you will only use the command line. Additionally, there are no Application Servers, Nodes, or Profiles. Instead, at it's core, the Application Client includes Java, so that you can use the Java command line tool. For example, let's say you have a JAR file that simply outputs "Hello World".

public class Main {
  public static void main(String[] args) {
    System.out.println("Hello World");
  }
}

The Application Client can be used to run the JAR which should output "Hello World".

~]$ /opt/WebSphere/profiles/your_profile/bin/launchClient.sh my.jar
IBM WebSphere Application Server, Release 8.5 
Java EE Application Client Tool 
Copyright IBM Corp., 1997-2011
WSCL0012I: Processing command line arguments.
WSCL0013I: Initializing the Java EE Application Client Environment.
WSCL0035I: Initialization of the Java EE Application Client Environment has completed.
WSCL0014I: Invoking the Application Client class Main
Hello World

The -CCverbose=true option can be used to include additional output. Or, you may want to try -CCtrace=true and -CCtracefile=trace.log.

~]$ /opt/WebSphere/profiles/your_profile/bin/launchClient.sh your.ear -CCverbose=true
IBM WebSphere Application Server, Release 8.5 
Java EE Application Client Tool 
Copyright IBM Corp., 1997-2011
WSCL0012I: Processing command line arguments.
WSCL0001I: Command line, property file, and system property arguments resolved to: 
        File to launch          = my.ear
        CC Property File        = null
        Client Jar File         = <default>
        Alternate DD            = null
        BootstrapHost           = 
        BootstrapPort           = <default>
        Trace enabled           = false
        Tracefile               = null
        Init only               = false
        Classpath Parameter     = null
        Security Manager        = disable
        Security Manager Class  = Not used. -CCsecurityManager=disable
        Security Manager Policy = Not used. -CCsecurityManager=disable
        Exit VM                 = false
        Soap Connector Port     = null
        Application Parameters  = 
        Provider URL            = null
        Dump Java Name Space    = null
        Admin Connector Host    = null
        Admin Connector Port    = null
        Admin Connector Type    = null
        Admin Connector User    = null
        PARENT_LAST mode        = false
WSCL0013I: Initializing the Java EE Application Client Environment.
WSCL0035I: Initialization of the Java EE Application Client Environment has completed.
WSCL0014I: Invoking the Application Client class Main
Hello World