WebSVN - MentaContainer - Blame - Rev 81 - /trunk/src/main/java/org/mentacontainer/Container.java

Rev	Author	Line No.	Line
2	soliveira	1	package org.mentacontainer;
		2
		3	/**
		4	* A very simple container that provides:
		5	* <ul>
		6	* <li> Bean instantiation (duh!)</li>
		7	* <li> Constructor injection for bean setup</li>
		8	* <li> Setter injection for bean setup</li>
81	soliveira	9	* <li> Wiring based on name and type</li>
57	soliveira	10	* <li> Scopes: Singleton and ThreadLocal</li>
20	soliveira	11	* <li> Wiring of external beans with the beans configured in this container</li>
25	soliveira	12	* <li> Annotation and XML free (programmatic configuration is the way to go!)
2	soliveira	13	* </ul>
		14	*
		15	* It does not get much simpler than that.
		16	*
		17	* @author sergio.oliveira.jr@gmail.com
		18	*
		19	*/
		20	public interface Container {
		21
		22	/**
		23	* Get an instance from the container.
		24	*
		25	* The instance will be fully initialized (constructor and/or setters) and fully wired.
		26	*
		27	* @param key The key representing the bean to return. The name of the bean in the container.
		28	* @return The fully initialized and wired bean.
		29	*/
41	soliveira	30	public <T> T get(String key);
2	soliveira	31
		32	/**
		33	* Configure a bean to be returned with the given implementation when {@link #get(String)} is called.
		34	*
		35	* @param key The key representing the bean to return. The name of the bean in the container.
		36	* @param klass The class used to instantiate the bean, in other words, its implementation.
57	soliveira	37	* @param scope The scope of the component.
45	soliveira	38	* @return The component created as a ConfigurableComponent. (Fluent API)
57	soliveira	39	* @see Scope
2	soliveira	40	*/
57	soliveira	41	public ConfigurableComponent ioc(String key, Class<? extends Object> klass, Scope scope);
2	soliveira	42
		43	/**
57	soliveira	44	* Same as {@link #ioc(String, Class, Scope)} except that it assumes
		45	* there is no scope (Scope.NONE).
2	soliveira	46	*
		47	* @param key
		48	* @param klass
45	soliveira	49	* @return The component created as a ConfigurableComponent. (Fluent API)
57	soliveira	50	* @see Scope
2	soliveira	51	*/
45	soliveira	52	public ConfigurableComponent ioc(String key, Class<?extends Object> klass);
2	soliveira	53
		54	/**
57	soliveira	55	* Set up IoC based on the component passed. The scope assumed is NONE.
2	soliveira	56	*
39	soliveira	57	* @param key The key representing the bean to return. The name of the bean in the container.
20	soliveira	58	* @param component The component for the IoC.
45	soliveira	59	* @return The component passed as a parameter.
21	soliveira	60	* @see Component
20	soliveira	61	*/
39	soliveira	62	public Component ioc(String key, Component component);
20	soliveira	63
		64	/**
57	soliveira	65	* Set up IoC based on the component passed. Specify the scope of the component.
51	soliveira	66	*
		67	* @param key The key representing the bean to return. The name of the bean in the container.
		68	* @param component The component for the IoC.
57	soliveira	69	* @param scope The scope used by the component.
51	soliveira	70	* @return The component passed as a parameter.
		71	* @see Component
57	soliveira	72	* @see Scope
51	soliveira	73	*/
57	soliveira	74	public Component ioc(String key, Component component, Scope scope);
51	soliveira	75
		76	/**
20	soliveira	77	* Configure a bean dependency to be auto-wired by the container. In general you want the
		78	* type of the dependency to be an interface, for loosely couple dependencies. It works like that:<br/><br/>
		79	*
2	soliveira	80	* Whenever the container returns a bean, it checks to see if it has a property named <i>property</i>
		81	* and if the type of the property is <i>klass</i>. If it does, then it looks for a bean named
		82	* <i>source</i> and injects it inside the first bean it is returning. This approach is recursive
		83	* so all properties are checked up the class hierarchy, until it reaches Object.
		84	*
		85	* @param property a bean property that will require another bean, in other words, the required
		86	* bean will be injected in the property of the bean been requested from the container. (auto-wiring by name)
20	soliveira	87	* @param klass the type of the dependency, in other words, the type of the auto-wiring. (auto-wiring by type)
2	soliveira	88	* @param source The dependency itself, coming from the container as well, in other words, the bean that will be injected in the original bean
		89	* @return The container itself. (Fluent API)
		90	*/
76	soliveira	91	public Dependency wire(String property, Class<? extends Object> klass, String source);
2	soliveira	92
		93	/**
76	soliveira	94	* Same as {@link #wire(String, Class, String)} except that it assumes that the property name will be the source name, in other words,
2	soliveira	95	* the property name is the same as the bean name that will be injected as the dependency.
		96	*
		97	* @param property
		98	* @param klass
		99	* @return The container itself. (Fluent API)
		100	*/
76	soliveira	101	public Dependency wire(String property, Class<? extends Object> klass);
2	soliveira	102
		103	/**
21	soliveira	104	* Setup a dependency.
2	soliveira	105	*
21	soliveira	106	* @param dependency The dependency to setup
		107	* @return The dependency itself. (Fluent API)
		108	* @see Dependency
2	soliveira	109	*/
76	soliveira	110	public Dependency wire(Dependency dependency);
2	soliveira	111
		112	/**
		113	* Take a given bean and populate its properties with other beans coming from this container. Perhaps you can call this auto-wiring.
		114	* You basically checking properties of the given bean and looking for values (by name and type!) inside the container. And injecting
		115	* in the given bean, in other words, populating it.
		116	*
		117	* @param bean The bean to be populated with other beans from the container.
		118	* @return The container itself. (Fluent API)
		119	*/
40	soliveira	120	public Container populate(Object bean);
4	soliveira	121
		122	/**
58	soliveira	123	* Check whether the container currently has a value for this key. For example,
		124	* if it is a singleton AND someone has requested it, the container will have it cached.
		125	* The method is useful to check for an instance without forcing her creation.
4	soliveira	126	*
		127	* @param key The key representing the bean inside the container.
58	soliveira	128	* @return true if the container has an instance cached in the scope for this key
4	soliveira	129	*/
58	soliveira	130	public boolean check(String key);
57	soliveira	131
		132	/**
81	soliveira	133	* Clear all cached instances for that scope. If you have a thread-pool for example you will
		134	* want to clear the THREAD scope when your thread is returned to the pool. Because you have a thread
		135	* pool you will have the SAME thread handling different requests and each request will need its own instances
		136	* from the container. Therefore, each time you are done with a thread and it is returned to your thread-pool
		137	* you can call clear to release the instances allocated and cached by the container. A web container and/or framework
		138	* can use this feature to implement a REQUEST scope which is nothing more than the THREAD scope with clear. If the web
		139	* container was not using a thread-pool, the THREAD scope would be equal to the REQUEST scope as each request would
		140	* always be handled by a different thread.
		141	*
		142	* It does not make sense to clear a NONE scope (the method returns doing nothing). You can clear a SINGLETON scope if necessary.
57	soliveira	143	*
		144	* @param scope The scope to be cleared.
		145	*/
		146	public void clear(Scope scope);
58	soliveira	147
		148	/**
		149	* Clear a single key from cache and return the instance that was cached.
		150	*
		151	* @param key The key representing the bean inside the container.
70	soliveira	152	* @return The value that was cached and it is not anymore (was cleared) or null if nothing was cleared
58	soliveira	153	*/
		154	public <T> T clear(String key);
2	soliveira	155	}

MentaContainer

(root)/trunk/src/main/java/org/mentacontainer/Container.java @ 93 - Rev 81