Monitoring on-premises J2SE applications

You can configure the J2SE data collector to monitor the on-premises J2SE applications running on stand-alone Docker containers, VMs, or physical nodes and then send monitoring data to the Monitoring server.

Before you begin

Check that you downloaded the configuration package to obtain the server information, for more information, see Obtaining the server configuration information.
Check whether you downloaded the J2SE data collector package. For more information, see Downloading the J2SE data collector.

Procedure

Extract the j2se_datacollector.tgz file that you get from Downloading the J2SE data collector.
```
tar -xf path-of-j2se_datacollector.tgz
```
With config_dc.sh script under J2SE data collector directory, and the ibm-cloud-apm-dc-configpack.tar that is downloaded in Obtaining the server configuration information, run the following command to apply server configuration to the monitored application:
```
path-of-j2se_datacollector.tgz/bin/config_dc.sh [-silent <silent_file>]
```
Note: If silent_file is not provided, the default silent_config_j2se_dc.txt under the same directory of config_dc.sh will be used.

Copy configpack files into J2SE data collector directory:

cp ./ibm-cloud-apm-dc-configpack/global.environment /opt/j2se_dc/itcamdc/etc
cp ./ibm-cloud-apm-dc-configpack/keyfiles/keyfile.jks /opt/j2se_dc/itcamdc/etc

Run mkdir ../logs.
Run the following command:
```
chmod +x path-of-j2se_datacollector.tgz/runtime/j2seAPPLICATION_ALIAS.HOSTNAME.APPLICATION_ALIAS/dcstartup.sh
```
Where:
- APPLICATION_ALIAS is the value that is configured in APPLICATION_ALIAS item in silent_file.
- The default value of HOSTNAME is localhost.
Run the following command:
```
sh -c path-of-j2se_datacollector.tgz/runtime/j2seAPPLICATION_ALIAS.HOSTNAME.APPLICATION_ALIAS/dcstartup.sh
```
Where:
- APPLICATION_ALIAS is the value that is configured in APPLICATION_ALIAS item in silent_file.
- The default value of HOSTNAME is localhost.
Note： If you run the J2SE application in a docker container, you can start the application in background by running the following command:
```
docker run -d -p <docker_port:app_port> j2seapp:1.0
```
Where docker_port is the docker port exposed, app_port is the application port, for example, 10090:8080.

If the J2SE application runs in a docker container, rebuild your docker container with J2SE data collector and configpack installed by running:

docker build -t < application image name >:< image tag >

Docker file example:

FROM ibmjava:8
WORKDIR /opt/j2se_dc
COPY /j2se_datacollector.tgz /opt/j2se_dc
RUN tar -xf /opt/j2se_dc/j2se_datacollector.tgz
COPY /silent_config_j2se_dc.txt /opt/j2se_dc/bin/
COPY /EmployeeWeb-1.0-SNAPSHOT.jar /opt/
COPY /ibm-cloud-apm-dc-configpack/global.environment /opt/j2se_dc/itcamdc/etc/
COPY /ibm-cloud-apm-dc-configpack/keyfiles/keyfile.jks /opt/j2se_dc/itcamdc/etc/
RUN /opt/j2se_dc/bin/config_dc.sh -silent
COPY /dcstartup.sh /opt/j2se_dc/runtime/j2sej2seApp.localhost.j2seApp/
COPY /del_slf4.sh /opt/j2se_dc/runtime/j2sej2seApp.localhost.j2seApp/
RUN chmod +x /opt/j2se_dc/runtime/j2sej2seApp.localhost.j2seApp/dcstartup.sh
RUN mkdir /opt/logs
ENTRYPOINT [ "sh", "-c", "/opt/j2se_dc/runtime/j2sej2seApp.localhost.j2seApp/dcstartup.sh" ]

Where:

/opt/j2se_dc is path-of-j2se_datacollector.tgz.
EmployeeWeb-1.0-SNAPSHOT.jar is the application name.
j2seApp is APPLICATION_ALIAS item value in silent_file.