InjectionProvider.java

package org.needle4j.injection;

import org.needle4j.NeedleTestcase;

/**
 * Provides an instances of {@code T} and verifies an injection target.
 * 
 * @param <T>
 *            - The type of the provided object.
 * 
 * 
 *            <pre>
 * Example for javax.inject.Qualifier:
 * 
 * public class InjectionProvider<User>() {
 * 	@Override
 * 	public boolean verify(final InjectionTargetInformation information) {
 * 	 return information.getAnnotation(CurrentUser.class) != null;
 * 	}
 * 
 * 	@Override
 * 	public Object getKey(final InjectionTargetInformation information) {
 * 	 return CurrentUser.class;
 * 	}
 * 
 * 	@Override
 * 	public User getInjectedObject(final Class<?> type) {
 * 	 return new User();
 * 	}
 * }
 * 
 * </pre>
 */
public interface InjectionProvider<T> extends InjectionVerifier {

    /**
     * Provides an instance of {@code T}.
     * 
     * @param injectionPointType
     *            the type of the injection target.
     * @return <T> instance of {@code T}
     */
    T getInjectedObject(Class<?> injectionPointType);

    /**
     * Returns a key object, which identifies the provided object.
     * 
     * @param injectionTargetInformation
     *            information about the injection point
     * @return the key of the provided object
     * 
     * @see NeedleTestcase#getInjectedObject(Object)
     */
    Object getKey(InjectionTargetInformation injectionTargetInformation);
}