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An aggregation of 1.4, 1.5 modules into an ROP client jar.
There is a newer version: 4.2.1
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 *   Licensed to the Apache Software Foundation (ASF) under one
 *  or more contributor license agreements.  See the NOTICE file
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 *  regarding copyright ownership.  The ASF licenses this file
 *  to you under the Apache License, Version 2.0 (the
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package org.apache.cayenne.di;

import org.apache.cayenne.ConfigurationException;

/**
 * A facade to the Cayenne DI container. To create an injector use {@link DIBootstrap}
 * static methods.
 * 
 * @since 3.1
 */
public interface Injector {

    /**
     * Returns a service instance bound in the container for a specific type. Throws
     *{@link ConfigurationException} if the type is not bound, or an instance can not be
     * created.
     */
     T getInstance(Class type) throws ConfigurationException;

    /**
     * Returns a service instance bound in the container for a specific binding key.
     * Throws {@link ConfigurationException} if the key is not bound, or an instance can
     * not be created.
     */
     T getInstance(Key key) throws ConfigurationException;

     Provider getProvider(Class type) throws ConfigurationException;

     Provider getProvider(Key key) throws ConfigurationException;

    /**
     * Performs field injection on a given object, ignoring constructor injection. Since
     * Cayenne DI injector returns fully injected objects, this method is rarely used
     * directly.
     * 
     * Note that using this method inside a custom DI {@link Provider} will most likely
     * result in double injection, as custom provider is wrapped in a field-injecting
     * provider by the DI container. Instead custom providers must initialize object
     * properties manually, obtaining dependencies from Injector.
     */
    void injectMembers(Object object);

    /**
     * A lifecycle method that let's the injector's services to clean up their state and
     * release resources. This method would normally generate a scope end event for the
     * injector's one and only singleton scope.
     */
    void shutdown();
}