Transformer includes several environment variables that you can modify to customize the following areas:
- Java Home Environment Variables
- Eclipse Environment Variables Java
- Java Environment Variables Mac
- Java_opts Environment Variable Windows
- User and group used to start Transformer as a service
- Java configuration options, including the Java heap size, remote debugging, and garbage collection
- Security Manager that restricts the runtime permissions of user libraries
- Path to JAR files to be added to the root classloader
Edit environment variable In the Advanced tab in the System Properties window, click Environment Variables. This will open the Environment Variables window. In either the System variables or the User variables section, look for the 'JAVAOPTIONS' variable. I am seeing an issue when using the buildpack with the introscope agent. I am attempting to set some -D options through the JAVAOPTS environment variable. The problem is that when I use environment variables in my -D options, for exampl. Data Collector loads the value of the version-specific environment variable and adds it to the SDCJAVAOPTS environment variable. When defining Java configuration options, avoid defining duplicate options. If you do define duplicates, the last option passed to the JVM usually takes precedence.
Modifying Environment Variables
The method that you use to modify environment variables depends on the TransformerJava Home Environment Variables
installation type:$TRANSFORMER_DIST/libexec/transformer-env.sh
file to modify environment variables.Use a text editor to edit the transformer-env.sh
file. Some of the environment variables in the file are commented out and do not reflect the default values. Be sure to uncomment the line when you change a variable value.
After you edit the file, restart Transformer Fall out boy from under the cork tree album download zip. from the command prompt to enable the changes.
Eclipse Environment Variables Java
$TRANSFORMER_DIST/libexec/transformerd-env.sh
file to modify environment variables.Use a text editor to edit the transformerd-env.sh
file.
After you edit the file, restart Transformer to enable the changes.
/usr/lib/systemd/system/transformer.service
file to modify environment variables. transformer.service
file using the same procedure that you use to override unit configuration files on a systemd init system. For an example, see 'Example 2. Overriding vendor settings' in this systemd.unit manpage.Then restart Transformer to enable the changes.
While adjusting some environment variables recently, I came across an odd issue with Docker, Spring Boot and JAVA_OPTS. JAVA_OPTS comes from the Tomcat/Catalina world and when searching for “Docker and javaopts” on Google you’ll find many references to just adding JAVA_OPTS to the Docker environment. After some testing, I found this to be incorrect when running a Spring Boot jar in a Docker container, I’ll explain why and give a solution in this post.
Before I start, let’s setup a basic test environment that prints out the current memory setup so we can test in various situations. I’ve created this repo as a test case and you can refer back to it when needed.
Test Application Setup
Looking at the sample code, we have a basic pom file that imports Spring Boot dependencies:
The main application is a single Java file that prints out memory details:
Running this app in IntelliJ with no memory settings will show some basic output with memory settings: Download msm download tool oppo a3s.
Changing the memory values to -Xmx3g -Xms3g
we get a different output:
Now that we have a baseline, let’s move onto the Docker stage.
Docker
The first thing we’ll do is setup a basic Dockerfile
similar to the one in the Spring Boot guide. Since the jar will be built in the target folder we grab it from there and place a renamed copy into the container.
To generate the jar, just run maven real quick.
The jar will then be in the target folder ready for building the Docker container.
Java Environment Variables Mac
With the jar and the Dockerfile
ready we can build the container from the base folder of the repository.
We can see the newly built image by listing our Docker images.
With our newly built container that will run Spring boot application let’s run it for the first time! Note: I’ll be cutting out some of the output lines to save space since we only care about the memory detail output.
First run looks good. Let’s try setting the JAVA_OPTS
as we’re used to!
Woah! The Xmx
and Xms
settings didn’t have any affect on the Java settings in the container! Something must be wrong here and it’s not immediately obvious if all you search for is for “Docker and javaopts” on Google. Spring Boot is smart enough to handle many passed in environment variables but those are application specific. For example, when you look for a value x.y.z
, Spring Boot will look in application.properties
by default for x.y.z
and in the environment variables for X_Y_Z
. Due to this, passing in the environment variable -e X_Y_Z=1234
can be used in your application when using a Docker container. However, since JAVA_OPTS
are used by Java and not in the application we run into this problem.
Java_opts Environment Variable Windows
After some searching, I came across the fact that JAVA_OPTS
are very specific to Catalina (Tomcat). Looking in the bin folder of a tomcat install you’ll find a shell script that handles passing JAVA_OPTS
into the exec
lines. With this info, we can now look to change the Dockerfile
to adjust for handling passed in environment variables. I named this new Dockerfile ExecDockerfile
so I can have both in the same repo.
The change needed to enable JAVA_OPTS
is to execute the Java line with an ENTRYPOINT exec
command and place the environment variable into the line.
Kp astrology software. Let’s rebuild the container but specify the new ExecDockerfile
specifically using the -f
flag.
Let’s run the container again.
Conclusion
By starting the jar with ENTRYPOINT exec java $JAVA_OPTS
, we’ve successfully enabled changing memory settings using Docker environment variables. If you think you’re changing the memory settings currently but are not passing in $JAVA_OPTS into your start line in some fashion, I suggest you look at your Dockerfile
config.