在struts2中有两种方式可以得到这些对象
1、非IoC方式
要获得上述对象,关键Struts 2中com.opensymphony.xwork2.ActionContext类。我们可以通过它的静态方法getContext()获取当前Action的上下文对象。有了这个对象我们想获得其他几个对象就好办了
ActionContext ctx = ActionContext .getContext(); Map session = ctx.getSession(); 细心的朋友可以发现这里的session是个map对象在Struts2中底层的session都被封装成了Map类型我们可以直接操作这个map 进行对session的写入和读取操作而不用去直接操作HttpSession对象
另外,org.apache.struts2.ServletActionContext作为辅助类(Helper Class),可以帮助您快捷地获得这几个对象。
HttpServletRequest request = ServletActionContext. getRequest(); HttpServletResponse response = ServletActionContext. getResponse(); HttpSession session = request.getSession(); 如果你只是想访问session的属性(Attribute),你也可以通过ActionContext .getContext().getSession()获取或添加session范围(Scoped)的对象。
2、IoC方式(这种方式在tapestry中也是这样实现的) 要使用IoC方式,我们首先要告诉IoC容器(Container)想取得某个对象的意愿,通过实现相应的接口做到这点。具体实现
- import java.util.Map;
- import javax.servlet.http.HttpServletRequest;
- import javax.servlet.http.HttpServletResponse;
- import javax.servlet.http.HttpSession;
- import org.apache.struts2.interceptor.ServletRequestAware;
- import org.apache.struts2.interceptor.ServletResponseAware;
- import org.apache.struts2.interceptor.SessionAware;
- import com.opensymphony.xwork2.ActionSupport;
- public class IoCServlet extends ActionSupport implements SessionAware,
- ServletRequestAware, ServletResponseAware {
- private String message;
- private Map att;
- private HttpServletRequest request;
- private HttpServletResponse response;
- public String getMessage() {
- return message;
- }
- public void setSession(Map att) {
- this.att = att;
- }
- public void setServletRequest(HttpServletRequest request) {
- this.request = request;
- }
- public void setServletResponse(HttpServletResponse response) {
- this.response = response;
- }
- @Override
- public String execute() {
- att.put("msg", "Hello World from Session!");
- HttpSession session = request.getSession();
- StringBuffer sb = new StringBuffer("Message from request: ");
- sb.append(request.getParameter("msg"));
- sb.append(" Response Buffer Size: ");
- sb.append(response.getBufferSize());
- sb.append(" Session ID: ");
- sb.append(session.getId());
- message = sb.toString();
- return "success";
- }
- }