Package org.picocontainer.parameters

Class CollectionComponentParameter

java.lang.Object
org.picocontainer.parameters.AbstractParameter
org.picocontainer.parameters.CollectionComponentParameter
All Implemented Interfaces:
Serializable, Parameter
public class CollectionComponentParameter extends AbstractParameter implements Parameter, Serializable
A CollectionComponentParameter should be used to support inject an Array, a Collectionor Mapof components automatically. The collection will contain all components of a special type and additionally the type of the key may be specified. In case of a map, the map's keys are the one of the component adapter.
Author:
Aslak Hellesøy, Jörg Schaible
See Also:

  • Field Details

  • Constructor Details

    • CollectionComponentParameter

      public CollectionComponentParameter()
      Expect an Arrayof an appropriate type as parameter. At least one component of the array's component type must exist.

    • CollectionComponentParameter

      public CollectionComponentParameter(boolean emptyCollection)
      Expect an Arrayof an appropriate type as parameter.
      Parameters:
      emptyCollection - true if an empty array also is a valid dependency resolution.

    • CollectionComponentParameter

      public CollectionComponentParameter(Class componentValueType, boolean emptyCollection)
      Expect any of the collection types Array,Collectionor Mapas parameter.
      Parameters:
      componentValueType - the type of the components (ignored in case of an Array)
      emptyCollection - true if an empty collection resolves the dependency.

    • CollectionComponentParameter

      public CollectionComponentParameter(Class componentKeyType, Class componentValueType, boolean emptyCollection)
      Expect any of the collection types Array,Collectionor Mapas parameter.
      Parameters:
      componentKeyType - the type of the component's key
      componentValueType - the type of the components (ignored in case of an Array)
      emptyCollection - true if an empty collection resolves the dependency.

  • Method Details

    • resolve

      public Parameter.Resolver resolve(PicoContainer container, ComponentAdapter<?> forAdapter, ComponentAdapter<?> injecteeAdapter, Type expectedType, NameBinding expectedNameBinding, boolean useNames, Annotation binding)
      Check for a successful dependency resolution of the parameter for the expected type. The dependency can only be satisfied if the expected type is one of the collection types Array,Collectionor Map. An empty collection is only a valid resolution, if the emptyCollection flag was set.
      Specified by:
      resolve in interface Parameter
      Parameters:
      container - the container from which dependencies are resolved.
      forAdapter - the ComponentAdapter that is asking for the instance
      injecteeAdapter -
      expectedType - the required type
      expectedNameBinding - Expected parameter name
      useNames -
      binding - @return true if matching components were found or an empty collective type is allowed

    • verify

      public void verify(PicoContainer container, ComponentAdapter<?> adapter, Type expectedType, NameBinding expectedNameBinding, boolean useNames, Annotation binding)
      Verify a successful dependency resolution of the parameter for the expected type. The method will only return if the expected type is one of the collection types Array, Collectionor Map. An empty collection is only a valid resolution, if the emptyCollection flag was set.
      Specified by:
      verify in interface Parameter
      Parameters:
      container - the container from which dependencies are resolved.
      adapter - the ComponentAdapter that is asking for the verification
      expectedType - the required type
      expectedNameBinding - Expected parameter name
      useNames -
      binding -
      Throws:
      PicoCompositionException - if parameter and its dependencies cannot be resolved

    • accept

      public void accept(PicoVisitor visitor)
      Visit the current Parameter.
      Specified by:
      accept in interface Parameter
      Parameters:
      visitor - the visitor.
      See Also:

    • evaluate

      protected boolean evaluate(ComponentAdapter adapter)
      Evaluate whether the given component adapter will be part of the collective type.
      Parameters:
      adapter - a ComponentAdapter value
      Returns:
      true if the adapter takes part

    • getMatchingComponentAdapters

      protected Map<Object,ComponentAdapter<?>> getMatchingComponentAdapters(PicoContainer container, ComponentAdapter adapter, Class keyType, Class valueType)
      Collect the matching ComponentAdapter instances.
      Parameters:
      container - container to use for dependency resolution
      adapter - ComponentAdapter to exclude
      keyType - the compatible type of the key
      valueType - the compatible type of the addComponent
      Returns:
      a Map with the ComponentAdapter instances and their component keys as map key.