import java.util.ArrayList;
import java.util.Date;
import java.util.List;
import java.util.Map;

import javax.servlet.ServletContext;
import javax.servlet.http.HttpSession;

import org.apache.struts2.ServletActionContext;
import org.apache.struts2.convention.annotation.Action;
import org.apache.struts2.convention.annotation.InterceptorRef;
import org.apache.struts2.convention.annotation.InterceptorRefs;
import org.apache.struts2.convention.annotation.Namespace;
import org.apache.struts2.convention.annotation.ParentPackage;
import org.apache.struts2.convention.annotation.Result;
import org.apache.struts2.convention.annotation.Results;

import com.opensymphony.xwork2.ActionContext;
import com.opensymphony.xwork2.ActionSupport;

import lombok.Data;

@Data
@Namespace("/")
@ParentPackage("struts-default")
public class ProductAction 
{
	private Product product;
	private List<Product> list;
	private List<Integer> checkList;
	private List<Category> categories=new ArrayList<>();
	private Date date;
	private String name;
	
	@Action(value="showProduct",results= {@Result(name="show",location="/show.jsp")})
	public String show()
	{
		product=new Product(1,"小米");
		HttpSession s=ServletActionContext.getRequest().getSession();
		s.setAttribute("name1", "苹果");
		Map map=ActionContext.getContext().getSession();
		map.put("name2", "oppo");
		return "show";
	}
	
	public String add()
	{
		System.out.println("product name: "+product.getName());
		return "show";
	}
	
	@Action(value="list",results= {@Result(name="success",location="/list.jsp")} 
	,interceptorRefs= {@InterceptorRef("InterceptorStack"),@InterceptorRef("defaultStack")})
	public String list()
	{
		list=new ArrayList<>();
		
		Product p1=new Product(1,"小米");
		Product p2=new Product(2, "华为");
		Product p3=new Product(3,"oppo");
		Product p4=new Product(4, "vivo");
		
		list.add(p1);
		list.add(p2);
		list.add(p3);
		list.add(p4);
		
		checkList=new ArrayList();
		checkList.add(1);
		checkList.add(2);
		
		Category c1=new Category(1,"c1",list);
		Category c2=new Category();
		c2.setId(2);
		c2.setName("c2");
		List<Product> list2=new ArrayList<Product>();
		list2.add(p4);
		list2.add(p3);
		c2.setProducts(list2);
		
		categories.add(c1);
		categories.add(c2);
		return "success";
	}
	
	public String addPage()
	{
		name="default_name";
		System.out.println(name);
		return "addPage";
	}
	
	
}

XML

<package name="basicstruts" extends="struts-default">
 
<interceptors >
<interceptor name="dateInterceptor" class="action.DateInterceptor"></interceptor>
<interceptor-stack name="InterceptorStack">
	<interceptor-ref name="dateInterceptor"/>
</interceptor-stack>

</interceptors> 

import org.apache.struts2.convention.annotation.Action;
import org.apache.struts2.convention.annotation.Namespace;
import org.apache.struts2.convention.annotation.ParentPackage;
import org.apache.struts2.convention.annotation.Result;
import org.apache.struts2.convention.annotation.Results;
import java.util.ArrayList;
import java.util.Date;
import java.util.List;
@Namespace("/")//表示默认路径下/下面定义的action
@ParentPackage("struts-default")//默认拦截器
@Results({
	@Result(name="show",location="/show.jsp")//返回的字符串 和跳转的jsp
})
public class ProductAction {
    private Product product;
    @Action("showProduct")
    public String show() {
    	
    	//用于控制product
        product = new Product();
        product.setName("iphone7");
        //这个返回值要和struts里对应Action里的一个result的name属性值相同
        return "show";
    }
    private String name;
    
    public String getName() {
        return name;
    }
 
    public void setName(String name) {
        this.name = name;
    }

Type Status Report

Message There is no Action mapped for namespace / and action name showProduct.

Description The origin server did not find a current representation for the target resource or is not willing to disclose that one exists.