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/* * 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.context.support; import org.springframework.beans.factory.BeanNameAware; import org.springframework.beans.factory.InitializingBean; import org.springframework.context.ApplicationContext; import org.springframework.lang.Nullable; import org.springframework.util.Assert; import org.springframework.util.StringUtils; /** * {@link AbstractRefreshableApplicationContext} subclass that adds common handling * of specified config locations. Serves as base class for XML-based application * context implementations such as {@link ClassPathXmlApplicationContext} and * {@link FileSystemXmlApplicationContext}, as well as * {@link org.springframework.web.context.support.XmlWebApplicationContext}. * * @author Juergen Hoeller * @since 2.5.2 * @see #setConfigLocation * @see #setConfigLocations * @see #getDefaultConfigLocations */ public abstract class AbstractRefreshableConfigApplicationContext extends AbstractRefreshableApplicationContext implements BeanNameAware, InitializingBean { @Nullable private String[] configLocations; private boolean setIdCalled = false; /** * Create a new AbstractRefreshableConfigApplicationContext with no parent. */ public AbstractRefreshableConfigApplicationContext() { } /** * Create a new AbstractRefreshableConfigApplicationContext with the given parent context. * @param parent the parent context */ public AbstractRefreshableConfigApplicationContext(@Nullable ApplicationContext parent) { super(parent); } /** * Set the config locations for this application context in init-param style, * i.e. with distinct locations separated by commas, semicolons or whitespace. * <p>If not set, the implementation may use a default as appropriate. */ public void setConfigLocation(String location) { setConfigLocations(StringUtils.tokenizeToStringArray(location, CONFIG_LOCATION_DELIMITERS)); } /** * Set the config locations for this application context. * <p>If not set, the implementation may use a default as appropriate. */ public void setConfigLocations(@Nullable String... locations) { if (locations != null) { Assert.noNullElements(locations, "Config locations must not be null"); this.configLocations = new String[locations.length]; for (int i = 0; i < locations.length; i++) { this.configLocations[i] = resolvePath(locations[i]).trim(); } } else { this.configLocations = null; } } /** * Return an array of resource locations, referring to the XML bean definition * files that this context should be built with. Can also include location * patterns, which will get resolved via a ResourcePatternResolver. * <p>The default implementation returns {@code null}. Subclasses can override * this to provide a set of resource locations to load bean definitions from. * @return an array of resource locations, or {@code null} if none * @see #getResources * @see #getResourcePatternResolver */ @Nullable protected String[] getConfigLocations() { return (this.configLocations != null ? this.configLocations : getDefaultConfigLocations()); } /** * Return the default config locations to use, for the case where no * explicit config locations have been specified. * <p>The default implementation returns {@code null}, * requiring explicit config locations. * @return an array of default config locations, if any * @see #setConfigLocations */ @Nullable protected String[] getDefaultConfigLocations() { return null; } /** * Resolve the given path, replacing placeholders with corresponding * environment property values if necessary. Applied to config locations. * @param path the original file path * @return the resolved file path * @see org.springframework.core.env.Environment#resolveRequiredPlaceholders(String) */ protected String resolvePath(String path) { return getEnvironment().resolveRequiredPlaceholders(path); } @Override public void setId(String id) { super.setId(id); this.setIdCalled = true; } /** * Sets the id of this context to the bean name by default, * for cases where the context instance is itself defined as a bean. */ @Override public void setBeanName(String name) { if (!this.setIdCalled) { super.setId(name); setDisplayName("ApplicationContext '" + name + "'"); } } /** * Triggers {@link #refresh()} if not refreshed in the concrete context's * constructor already. */ @Override public void afterPropertiesSet() { if (!isActive()) { refresh(); } } }