Package org.pipservices3.container

Class Container

java.lang.Object
org.pipservices3.container.Container
All Implemented Interfaces:
org.pipservices3.commons.config.IConfigurable, org.pipservices3.commons.refer.IReferenceable, org.pipservices3.commons.refer.IUnreferenceable, org.pipservices3.commons.run.IClosable, org.pipservices3.commons.run.IOpenable
Direct Known Subclasses:
ProcessContainer
public class Container extends Object implements org.pipservices3.commons.config.IConfigurable, org.pipservices3.commons.refer.IReferenceable, org.pipservices3.commons.refer.IUnreferenceable, org.pipservices3.commons.run.IOpenable
Inversion of control (IoC) container that creates components and manages their lifecycle.

The container is driven by configuration, that usually stored in JSON or YAML file. The configuration contains a list of components identified by type or locator, followed by component configuration.

On container start it performs the following actions:

  • Creates components using their types or calls registered factories to create components using their locators
  • Configures components that implement IConfigurable interface and passes them their configuration parameters
  • Sets references to components that implement IReferenceable interface and passes them references of all components in the container
  • Opens components that implement IOpenable interface

On container stop actions are performed in reversed order:

  • Closes components that implement IClosable interface
  • Unsets references in components that implement IUnreferenceable interface
  • Destroys components in the container.

The component configuration can be parameterized by dynamic values. That allows specialized containers to inject parameters from command line or from environment variables.

The container automatically creates a ContextInfo component that carries detail information about the container and makes it available for other components.

### Configuration parameters ###

  • name: the context (container or process) name
  • description: human-readable description of the context
  • properties: entire section of additional descriptive properties
  • ...

### Example ### 

 
 ======= config.yml ========
 - descriptor: mygroup:mycomponent1:default:default:1.0
   param1: 123
   param2: ABC

 - type: mycomponent2,mypackage
   param1: 321
   param2: XYZ
 ============================

 Container container = new Container();
 container.addFactory(new MyComponentFactory());

 ConfigParams parameters = ConfigParams.fromValue(process.env);
 container.readConfigFromFile("123", "./config/config.yml", parameters);

 container.open("123");
 System.out.println("Container is opened");
 ...
 container.close("123");
 System.out.println("Container is closed");
See Also:
  • IConfigurable
  • IReferenceable
  • IOpenable

  • Field Details

    • _logger

      protected org.pipservices3.components.log.ILogger _logger

    • _factories

      protected DefaultContainerFactory _factories

    • _info

      protected org.pipservices3.components.info.ContextInfo _info

    • _config

      protected ContainerConfig _config

    • _references

      protected ContainerReferences _references

  • Constructor Details

    • Container

      public Container(String name, String description)
      Creates a new instance of the container.
      Parameters:
      name - (optional) a container name (accessible via ContextInfo)
      description - (optional) a container description (accessible via ContextInfo)

    • Container

      public Container(ContainerConfig config)
      Creates a new instance of the container.
      Parameters:
      config - container configuration

  • Method Details

    • getConfig

      public ContainerConfig getConfig()

    • setConfig

      public void setConfig(ContainerConfig value)

    • getReferences

      public org.pipservices3.commons.refer.IReferences getReferences()

    • configure

      public void configure(org.pipservices3.commons.config.ConfigParams config) throws org.pipservices3.commons.errors.ConfigException
      Configures component by passing configuration parameters.
      Specified by:
      configure in interface org.pipservices3.commons.config.IConfigurable
      Parameters:
      config - configuration parameters to be set.
      Throws:
      org.pipservices3.commons.errors.ConfigException - when configuration is wrong.

    • readConfigFromFile

      public void readConfigFromFile(String correlationId, String path, org.pipservices3.commons.config.ConfigParams parameters) throws org.pipservices3.commons.errors.ApplicationException
      Reads container configuration from JSON or YAML file and parameterizes it with given values.
      Parameters:
      correlationId - (optional) transaction id to trace execution through call chain.
      path - a path to configuration file
      parameters - values to parameters the configuration or null to skip parameterization.
      Throws:
      org.pipservices3.commons.errors.ApplicationException - when error occured.

    • setReferences

      public void setReferences(org.pipservices3.commons.refer.IReferences references) throws org.pipservices3.commons.refer.ReferenceException, org.pipservices3.commons.errors.ConfigException
      Sets references to dependent components.
      Specified by:
      setReferences in interface org.pipservices3.commons.refer.IReferenceable
      Parameters:
      references - references to locate the component dependencies.
      Throws:
      org.pipservices3.commons.refer.ReferenceException - when no found references.
      org.pipservices3.commons.errors.ConfigException - when configuration is wrong

    • unsetReferences

      public void unsetReferences()
      Unsets (clears) previously set references to dependent components.
      Specified by:
      unsetReferences in interface org.pipservices3.commons.refer.IUnreferenceable

    • addFactory

      public void addFactory(org.pipservices3.components.build.IFactory factory)
      Adds a factory to the container. The factory is used to create components added to the container by their locators (descriptors).
      Parameters:
      factory - a component factory to be added.

    • isOpen

      public boolean isOpen()
      Checks if the component is opened.
      Specified by:
      isOpen in interface org.pipservices3.commons.run.IOpenable
      Returns:
      true if the component has been opened and false otherwise.

    • open

      public void open(String correlationId) throws org.pipservices3.commons.errors.ApplicationException
      Opens the component.
      Specified by:
      open in interface org.pipservices3.commons.run.IOpenable
      Parameters:
      correlationId - (optional) transaction id to trace execution through call chain.
      Throws:
      org.pipservices3.commons.errors.ApplicationException - when error occured.

    • close

      public void close(String correlationId) throws org.pipservices3.commons.errors.ApplicationException
      Closes component and frees used resources.
      Specified by:
      close in interface org.pipservices3.commons.run.IClosable
      Parameters:
      correlationId - (optional) transaction id to trace execution through call chain.
      Throws:
      org.pipservices3.commons.errors.ApplicationException - when error occured.