Java tutorial
/** * Copyright 2013-2014 Guoqiang Chen, Shanghai, China. All rights reserved. * * Email: subchen@gmail.com * URL: http://subchen.github.io/ * * 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 * * http://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 jetbrick.ioc.injectors; import java.lang.annotation.Annotation; import javax.servlet.ServletContext; import jetbrick.ioc.Ioc; import jetbrick.ioc.annotations.SpringBean; import jetbrick.lang.Validate; import jetbrick.lang.annotations.ValueConstants; import jetbrick.reflect.FieldInfo; import org.springframework.context.ApplicationContext; import org.springframework.web.context.support.WebApplicationContextUtils; // @SpringBean public class SpringBeanFieldInjector implements FieldInjector { private ApplicationContext appctx; private String name; private FieldInfo field; private boolean required; @Override public void initialize(FieldContext ctx) { Annotation annotation = ctx.getAnnotation(); Validate.isInstanceOf(SpringBean.class, annotation); SpringBean inject = (SpringBean) annotation; this.appctx = getApplicationContext(ctx.getIoc()); this.field = ctx.getField(); this.name = ValueConstants.defaultValue(inject.value(), ctx.getFieldName()); // ??? this.required = inject.required(); } private ApplicationContext getApplicationContext(Ioc ioc) { ApplicationContext ctx = ioc.getBean(ApplicationContext.class); if (ctx != null) { return ctx; } ServletContext sc = ioc.getBean(ServletContext.class); if (sc != null) { ctx = WebApplicationContextUtils.getWebApplicationContext(sc); } if (ctx == null) { throw new IllegalStateException("No Spring Found!"); } return ctx; } @Override public void set(Object object) throws Exception { Object value = appctx.getBean(name); if (value == null && required) { throw new IllegalStateException("Can't inject bean: " + name + " for field: " + field); } field.set(object, value); } }