package com.whyc.config;

import javax.servlet.ServletContext;
import javax.servlet.ServletContextEvent;
import javax.servlet.ServletContextListener;
import javax.servlet.annotation.WebListener;

import org.springframework.beans.BeansException;
import org.springframework.context.ApplicationContext;
import org.springframework.context.ApplicationContextAware;
import org.springframework.stereotype.Component;
import org.springframework.util.Assert;

/**
 * @author ypp 创建时间：2018年10月17日 上午11:59:11
 * @Description: TODO(用一句话描述该文件做什么)
 */
@Component
@WebListener
public class SpringBeanTool implements ApplicationContextAware, ServletContextListener {

    /**
     * 上下文对象实例
     */
    private ApplicationContext applicationContext;

    private ServletContext servletContext;

    @Override
    public void setApplicationContext(ApplicationContext applicationContext) throws BeansException {
        this.applicationContext = applicationContext;
    }

    /**
     * 获取applicationContext
     *
     * @return
     */
    public ApplicationContext getApplicationContext() {
        return applicationContext;
    }

    /**
     * 获取servletContext
     *
     * @return
     */
    public ServletContext getServletContext() {
        return servletContext;
    }

    /**
     * 通过name获取 Bean.
     *
     * @param name
     * @return
     */
    public Object getBean(String name) {
        return getApplicationContext().getBean(name);
    }

    /**
     * 通过class获取Bean.
     *
     * @param clazz
     * @param <T>
     * @return
     */
    public <T> T getBean(Class<T> clazz) {
        return getApplicationContext().getBean(clazz);
    }

    /**
     * 通过name,以及Clazz返回指定的Bean
     *
     * @param name
     * @param clazz
     * @param <T>
     * @return
     */
    public <T> T getBean(String name, Class<T> clazz) {
        Assert.hasText(name, "name为空");
        return getApplicationContext().getBean(name, clazz);
    }

    @Override
    public void contextInitialized(ServletContextEvent sce) {
        this.servletContext = sce.getServletContext();
    }

    @Override
    public void contextDestroyed(ServletContextEvent sce) {

    }

}