1.通过ServletActionContext类

//获取request对象HttpServletRequest request = ServletActionContext.getRequest();//保存值到application中ServletActionContext.getActionContext(request).setApplication(new HashMap<>());

2.通过ServletRequestAware 接口

public class UserAction extends ActionSupport implements ServletRequestAware {    private String username;    private String userpwd;    private HttpServletRequest request;    public String getUsername() {        return username;    }    public void setUsername(String username) {        this.username = username;    }    public String getUserpwd() {        return userpwd;    }    public void setUserpwd(String userpwd) {        this.userpwd = userpwd;    }    @Override    public void setServletRequest(HttpServletRequest arg0) {        this.request = arg0;    }    public void executeAjax() throws IOException {        // 处理Ajax请求        String name = request.getParameter("username");                String pwd = request.getParameter("userpwd");        HttpServletResponse response = ServletActionContext.getResponse();                response.getWriter().print("hello"+username+"hello"+userpwd);            }    }