public ContainerDefinition withEnvironmentFiles(java.util.Collection<EnvironmentFile> environmentFiles) {
        setEnvironmentFiles(environmentFiles);
        return this;
    }
<p>
A list of files containing the environment variables to pass to a container. This parameter maps to the
<code>--env-file</code> option to <a
href="https://docs.docker.com/engine/reference/run/#security-configuration">docker run</a>.
</p>
<p>
You can specify up to ten environment files. The file must have a <code>.env</code> file extension. Each line in
an environment file contains an environment variable in <code>VARIABLE=VALUE</code> format. Lines beginning with
<code>#</code> are treated as comments and are ignored. For more information about the environment variable file
syntax, see <a href="https://docs.docker.com/compose/env-file/">Declare default environment variables in
file</a>.
</p>
<p>
If there are environment variables specified using the <code>environment</code> parameter in a container
definition, they take precedence over the variables contained within an environment file. If multiple environment
files are specified that contain the same variable, they're processed from the top down. We recommend that you
use unique variable names. For more information, see <a
href="https://docs.aws.amazon.com/AmazonECS/latest/developerguide/taskdef-envfiles.html">Specifying Environment
Variables</a> in the <i>Amazon Elastic Container Service Developer Guide</i>.
</p>

@param environmentFiles
       A list of files containing the environment variables to pass to a container. This parameter maps to the
       <code>--env-file</code> option to <a
       href="https://docs.docker.com/engine/reference/run/#security-configuration">docker run</a>.</p>
       <p>
       You can specify up to ten environment files. The file must have a <code>.env</code> file extension. Each
       line in an environment file contains an environment variable in <code>VARIABLE=VALUE</code> format. Lines
       beginning with <code>#</code> are treated as comments and are ignored. For more information about the
       environment variable file syntax, see <a href="https://docs.docker.com/compose/env-file/">Declare default
       environment variables in file</a>.
       </p>
       <p>
       If there are environment variables specified using the <code>environment</code> parameter in a container
       definition, they take precedence over the variables contained within an environment file. If multiple
       environment files are specified that contain the same variable, they're processed from the top down. We
       recommend that you use unique variable names. For more information, see <a
       href="https://docs.aws.amazon.com/AmazonECS/latest/developerguide/taskdef-envfiles.html">Specifying
       Environment Variables</a> in the <i>Amazon Elastic Container Service Developer Guide</i>.
@return Returns a reference to this object so that method calls can be chained together.
aws-java-sdk-ecs/src/main/java/com/amazonaws/services/ecs/model/ContainerDefinition.java