启动加载缓存

最新推荐文章于 2025-05-16 14:00:00 发布

原创最新推荐文章于 2025-05-16 14:00:00 发布 · 925 阅读

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1.web.xml引入

  <servlet>
    <servlet-name>InitServlet</servlet-name>
    <servlet-class>com.hxy.sys.servelt.InitServlet</servlet-class>
    <load-on-startup>1</load-on-startup>
  </servlet>

2.InitServlet类

import com.hxy.base.utils.SpringContextUtils;
import com.hxy.sys.dao.CodeDao;
import javax.servlet.ServletConfig;
import javax.servlet.ServletException;
import javax.servlet.http.HttpServlet;
import java.util.ArrayList;
import java.util.HashMap;
import java.util.List;
import java.util.Map;

/**
 * 类的功能描述.
 * 继承HttpServlet，重写Init方法，实现加载servlet时，做一些操作
 */
public class InitServlet extends HttpServlet{
    private static CodeDao codeDao = SpringContextUtils.getBean(CodeDao.class);
    @Override
    public void init(ServletConfig config) throws ServletException {
        super.init(config);

ApplicationContext context1 = WebApplicationContextUtils.getWebApplicationContext(config.getServletContext());
SystemApi aaabbbb = context1.getBean(SystemApi.class);

String webRoot = config.getServletContext().getContextPath(); config.getServletContext().setAttribute("webRoot", webRoot);//Web根目录 config.getServletContext().setAttribute("resRoot", webRoot+"/statics");//资态资源根目录 //缓存全部数据字典 CodeCache(); } /** * 缓存全部数据字典 */ public void CodeCache(){ ........................ }}

3.工具类

import org.apache.commons.lang3.Validate;
import org.springframework.beans.BeansException;
import org.springframework.context.ApplicationContext;
import org.springframework.context.ApplicationContextAware;
import org.springframework.stereotype.Component;

/**
 * 类SpringContextUtils的功能描述:
 * Spring Context 工具类
 */
@Component
public class SpringContextUtils implements ApplicationContextAware {
	public static ApplicationContext applicationContext;
	@Override
	public void setApplicationContext(ApplicationContext applicationContext)   throws BeansException {
		SpringContextUtils.applicationContext = applicationContext;
	}
	public static Object getBean(String name) {
		return applicationContext.getBean(name);
	}
	/**
	 * 从静态变量applicationContext中取得Bean, 自动转型为所赋值对象的类型.
	 */
	public static <T> T getBean(Class<T> requiredType) {
		assertContextInjected();
		return applicationContext.getBean(requiredType);
	}
	/**
	 * 检查ApplicationContext不为空.
	 */
	private static void assertContextInjected() {
		Validate.validState(applicationContext != null, "applicaitonContext属性未注入, 请在applicationContext.xml中定义SpringContextHolder.");
	}
	public static <T> T getBean(String name, Class<T> requiredType) {
		return applicationContext.getBean(name, requiredType);
	}
	public static boolean containsBean(String name) {
		return applicationContext.containsBean(name);
	}
	public static boolean isSingleton(String name) {
		return applicationContext.isSingleton(name);
	}
	public static Class<? extends Object> getType(String name) {
		return applicationContext.getType(name);
	}
}

加载SpringContextUtils到容器

    <bean class="com.bbbb.aaa.base.utils.SpringContextUtil" lazy-init="false"/>