Struts2.18 的 interceptor

首先定义我们自己的Interceptor

package com.web.interceptor;

import javax.servlet.http.HttpServletRequest;
import org.apache.struts2.StrutsStatics;
import org.apache.struts2.convention.annotation.ParentPackage;

import com.common.utils.StringUtil;
import com.opensymphony.xwork2.ActionContext;
import com.opensymphony.xwork2.ActionInvocation;
import com.opensymphony.xwork2.interceptor.AbstractInterceptor;
import com.opensymphony.xwork2.util.ValueStack;
import com.web.action.Constants;

@ParentPackage(value="struts-default")
public class LoginInterceptor extends AbstractInterceptor
{
	/**
	 * 
	 */
	private static final long serialVersionUID = 1L;

	public static final String USER_SESSION_KEY="wallet.session.user";
	
	public void init()
	{}
	
	@SuppressWarnings("unchecked")
	@Override
	public String intercept(ActionInvocation invocation) throws Exception
	{ 
		ActionContext actionContext = invocation.getInvocationContext();
		HttpServletRequest request = (HttpServletRequest) actionContext.get(StrutsStatics.HTTP_REQUEST);

		String uri = request.getRequestURI();
		if(uri.indexOf("index.action")>-1)
		{
			return Constants.INPUT; 
		}
		else if(uri.indexOf("login.action")>-1)
		{
			ValueStack vt = actionContext.getValueStack();
			java.util.Map<String, Object> mp = vt.getContext();
			
			java.util.Map<String, Object> paraMap = (java.util.Map<String,Object>)mp.get(ActionContext.PARAMETERS);
			String[] name = (String[])paraMap.get("user.name");
		 
			//String name = (String)vt.findValue("user.name");
			if(name!=null && name.length>0 && !StringUtil.hasContent(name[0]))
			{
				vt.set("fielderror", "必须输入用户名!");
				return Constants.INPUT;
			}
			else return invocation.invoke();
		}
		else
			return invocation.invoke();
	}

	public void destroy()
	{}
}

将其注册到struts中，修改struts2.xml文件增加如下内容：

<package name="struts-interceptor" extends="struts-default"> 
		<interceptors> 
		    <interceptor name="loginInterceptor" class="com.web.interceptor.LoginInterceptor"/>
		</interceptors> 
	</package> 

这样我们自己定义的Interceptor已经设置完成，如果想使用则可以用annotation指定。如

@InterceptorRefs({
  @InterceptorRef("loginInterceptor"),
  @InterceptorRef("defaultStack")
})
@ParentPackage(value="struts-interceptor")  
@Namespace(value="/application")  
@Result(name="input",location="/application/login.jsp")
public class LoginAction extends BaseAction
{
	private static final long serialVersionUID = 1L;
}	

我们在LoginAction里使用了刚刚自定义的Interceptor。

官网教程提供的解决方案：

引用

If you get errors like "Unable to find interceptor class referenced by ref-name XYZ". This means that the package where Convention is placing your actions, does not extend the package where the interceptor is defined. To fix this problem either 1)Use @ParentPackage annotation(or struts.convention.default.parent.package) passing the name of the package that defines the interceptor, or 2) Create a package in XML that extends the package that defines the interceptor, and use @ParentPackage(or struts.convention.default.parent.package) to point to it.