Package org.apache.struts2.inject

Interface Container

All Superinterfaces:
Serializable
All Known Implementing Classes:
MockContainer
public interface Container extends Serializable

Injects dependencies into constructors, methods and fields annotated with Inject. Immutable.

When injecting a method or constructor, you can additionally annotate its parameters with Inject and specify a dependency name. When a parameter has no annotation, the container uses the name from the method or constructor's Inject annotation respectively.

For example:

  class Foo {

    // Inject the int constant named "i".
    @Inject("i") int i;

    // Inject the default implementation of Bar and the String constant
    // named "s".
    @Inject Foo(Bar bar, @Inject("s") String s) {
      ...
    }

    // Inject the default implementation of Baz and the Bob implementation
    // named "foo".
    @Inject void initialize(Baz baz, @Inject("foo") Bob bob) {
      ...
    }

    // Inject the default implementation of Tee.
    @Inject void setTee(Tee tee) {
      ...
    }
  }

To create and inject an instance of Foo:

  Container c = ...;
  Foo foo = c.inject(Foo.class);
Author:
crazybob@google.com (Bob Lee)
See Also:

  • Field Summary

    Fields
    Modifier and Type
    Field
    Description
    static final String
    DEFAULT_NAME
    Default dependency name.

  • Method Summary

    Modifier and Type
    Method
    Description
    <T> T
    getInstance(Class<T> type)
    Convenience method. Equivalent to getInstance(type, DEFAULT_NAME).
    <T> T
    getInstance(Class<T> type, String name)
    Gets an instance of the given dependency which was declared in ContainerBuilder.
    Set<String>
    getInstanceNames(Class<?> type)
    Gets a set of all registered names for the given type
    <T> T
    inject(Class<T> implementation)
    Creates and injects a new instance of type implementation.
    void
    inject(Object o)
    Injects dependencies into the fields and methods of an existing object.
    void
    removeScopeStrategy()
    Removes the scope strategy for the current thread.
    void
    setScopeStrategy(Scope.Strategy scopeStrategy)
    Sets the scope strategy for the current thread.

  • Field Details

  • Method Details

    • inject

      void inject(Object o)
      Injects dependencies into the fields and methods of an existing object.
      Parameters:
      o - object to inject

    • inject

      <T> T inject(Class<T> implementation)
      Creates and injects a new instance of type implementation.
      Type Parameters:
      T - type
      Parameters:
      implementation - of dependency
      Returns:
      instance

    • getInstance

      <T> T getInstance(Class<T> type, String name)
      Gets an instance of the given dependency which was declared in ContainerBuilder.
      Type Parameters:
      T - type
      Parameters:
      type - of dependency
      name - of dependency
      Returns:
      instance

    • getInstance

      <T> T getInstance(Class<T> type)
      Convenience method. Equivalent to getInstance(type, DEFAULT_NAME).
      Type Parameters:
      T - type
      Parameters:
      type - of dependency
      Returns:
      instance

    • getInstanceNames

      Set<String> getInstanceNames(Class<?> type)
      Gets a set of all registered names for the given type
      Parameters:
      type - The instance type
      Returns:
      A set of registered names or empty set if no instances are registered for that type

    • setScopeStrategy

      void setScopeStrategy(Scope.Strategy scopeStrategy)
      Sets the scope strategy for the current thread.
      Parameters:
      scopeStrategy - scope strategy

    • removeScopeStrategy

      void removeScopeStrategy()
      Removes the scope strategy for the current thread.