Java tutorial
/* * Copyright 2002-2017 the original author or authors. * * Licensed under the Apache License, Version 2.0 (the "License"); * you may not use this file except in compliance with the License. * You may obtain a copy of the License at * * https://www.apache.org/licenses/LICENSE-2.0 * * Unless required by applicable law or agreed to in writing, software * distributed under the License is distributed on an "AS IS" BASIS, * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. * See the License for the specific language governing permissions and * limitations under the License. */ package org.springframework.core.env; /** * Interface indicating a component that contains and exposes an {@link Environment} reference. * * <p>All Spring application contexts are EnvironmentCapable, and the interface is used primarily * for performing {@code instanceof} checks in framework methods that accept BeanFactory * instances that may or may not actually be ApplicationContext instances in order to interact * with the environment if indeed it is available. * * <p>As mentioned, {@link org.springframework.context.ApplicationContext ApplicationContext} * extends EnvironmentCapable, and thus exposes a {@link #getEnvironment()} method; however, * {@link org.springframework.context.ConfigurableApplicationContext ConfigurableApplicationContext} * redefines {@link org.springframework.context.ConfigurableApplicationContext#getEnvironment * getEnvironment()} and narrows the signature to return a {@link ConfigurableEnvironment}. * The effect is that an Environment object is 'read-only' until it is being accessed from * a ConfigurableApplicationContext, at which point it too may be configured. * * @author Chris Beams * @since 3.1 * @see Environment * @see ConfigurableEnvironment * @see org.springframework.context.ConfigurableApplicationContext#getEnvironment() */ public interface EnvironmentCapable { /** * Return the {@link Environment} associated with this component. */ Environment getEnvironment(); }