To add a container, the class file must be located in lib/java_buildpack/container and the class name added to config/components.yml. The class must have the following methods
# An initializer for the instance.
#
# @param [Hash<Symbol, String>] context A shared context provided to all components
# @option context [String] :app_dir the directory that the application exists in
# @option context [Hash] :environment A hash containing all environment variables except +VCAP_APPLICATION+ and
# +VCAP_SERVICES+. Those values are available separately in parsed form.
# @option context [String] :java_home the directory that acts as +JAVA_HOME+
# @option context [Array<String>] :java_opts an array that Java options can be added to
# @option context [String] :lib_directory the directory that additional libraries are placed in
# @option context [Hash] :vcap_application The contents of the +VCAP_APPLICATION+ environment variable
# @option context [Hash] :vcap_services The contents of the +VCAP_SERVICES+ environment variable
# @option context [Hash] :configuration the configuration provided by the user
def initialize(context)
# Determines if the container can be used to run the application.
#
# @return [Array<String>, String, nil] If the container can be used to run the application, a +String+ or an
# +Array<String>+ that uniquely identifies the container (e.g.
# +tomcat-7.0.29+). Otherwise, +nil+.
def detect
# Downloads and unpacks the container. The container is expected to transform the application in whatever way
# necessary (e.g. moving files or creating symbolic links) to run it. Status output written to +STDOUT+ is expected as
# part of this invocation.
#
# @return [void]
def compile
# Creates the command to run the application with. The container is expected to read +context[:java_home]+ and
# +context[:java_opts]+ and take those values into account when creating the command.
#
# @return [String] the command to run the application with
def release