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java为避免struts,自定义拦截器类和包应该使用什么命名约定。Struts2中的xml

我想知道struts2中是否有命名自定义拦截器的约定,用于自动检测拦截器,就像操作类一样

我正在使用“struts2-convention-plugin-2.3.24.1.jar

包结构如下

ProtienTracker
    >Java Resources
        >src
            >com.nagarro.actions
                >HelloAction.java
            >com.nagarro.interceptors
                >custInterceptor.java
    >WebContent
        >META_INF
        >WEB_INF
            >content
                >hello.jsp
            >lib
        >web.xml

代码在没有“struts.xml”和“custInterceptor”的情况下运行完美。struts2约定插件会自动检测到该操作

只要我把拦截器装上

@org.apache.struts2.convention.annotation.Action(value="hello",
    interceptorRefs=@InterceptorRef("custInterceptor"))

我得到的错误如下所示

文件如下

你好。jsp

<%@ page language="java" contentType="text/html; charset=ISO-8859-1"
pageEncoding="ISO-8859-1"%>
<%@ taglib prefix="s" uri="/struts-tags" %>
<!DOCTYPE html PUBLIC "-//W3C//DTD HTML 4.01 Transitional//EN" "http://www.w3.org/TR/html4/loose.dtd">
<html>
<head>
    <meta http-equiv="Content-Type" content="text/html; charset=ISO-8859-1">
    <title>Hello</title>
</head>
<body>
    <h1><s:property value="greeting"/></h1>
    <p>hi</p>
</body>
</html>

你好。爪哇

package com.nagarro.actions;
import com.opensymphony.xwork2.Action;

import org.apache.struts2.convention.annotation.InterceptorRef;
import org.apache.struts2.convention.annotation.Result;
public class HelloAction implements Action {

    private String greeting="ab";

    @Override
    @org.apache.struts2.convention.annotation.Action(value="hello",
    interceptorRefs=@InterceptorRef("custInterceptor"))
    public String execute() throws Exception {
        setGreeting("Hello Structs 2");
        return "success";
    }

    public String getGreeting() {
        return greeting;
    }

    public void setGreeting(String greeting) {
        this.greeting = greeting;
    }

}

拦截者。爪哇

package com.nagarro.interceptors;

import com.opensymphony.xwork2.ActionInvocation;
import com.opensymphony.xwork2.interceptor.Interceptor;

public class custInterceptor implements Interceptor{

    private static final long serialVersionUID = 1L;

    @Override
    public void destroy() {
        System.out.println("custInterceptor destroy() is called...");

    }

    @Override
    public void init() {
        System.out.println("custInterceptor init() is called...");

    }

    @Override
    public String intercept(ActionInvocation invocation) throws Exception {
        System.out.println("custInterceptor intercept() is called...");
        System.out.println(invocation.getAction().getClass().getName());
        return invocation.invoke();
    }

}

我得到以下错误:

Caused by: Unable to find interceptor class referenced by ref-name custInterceptor - [unknown location]
        at com.opensymphony.xwork2.config.providers.InterceptorBuilder.constructInterceptorReference(InterceptorBuilder.java:63)
        at org.apache.struts2.convention.DefaultInterceptorMapBuilder.buildInterceptorList(DefaultInterceptorMapBuilder.java:95)
        at org.apache.struts2.convention.DefaultInterceptorMapBuilder.build(DefaultInterceptorMapBuilder.java:86)
        at org.apache.struts2.convention.DefaultInterceptorMapBuilder.build(DefaultInterceptorMapBuilder.java:70)
        at org.apache.struts2.convention.PackageBasedActionConfigBuilder.createActionConfig(PackageBasedActionConfigBuilder.java:947)
        at org.apache.struts2.convention.PackageBasedActionConfigBuilder.buildConfiguration(PackageBasedActionConfigBuilder.java:734)
        at org.apache.struts2.convention.PackageBasedActionConfigBuilder.buildActionConfigs(PackageBasedActionConfigBuilder.java:355)
        at org.apache.struts2.convention.ClasspathPackageProvider.loadPackages(ClasspathPackageProvider.java:53)
        at com.opensymphony.xwork2.config.impl.DefaultConfiguration.reloadContainer(DefaultConfiguration.java:274)
        at com.opensymphony.xwork2.config.ConfigurationManager.getConfiguration(ConfigurationManager.java:67)
        ... 17 more

共 (1) 个答案

  1. # 1 楼答案

    define interceptors with struts2 annotations所述

    you cannot eliminate a need of struts.xml if you are using custom interceptors.

    要在xml中定义一个新的拦截器,需要在struts中定义它。xml文件

    <struts>
        ......
     <package name="my-default" extends="struts-default" />
    
       <!  Define the intercepor class and give it a name >
        <interceptors>
           <interceptor name="custInterceptor"  class=com.nagarro.interceptors.custInterceptor" />
        </interceptors>
    
       <!  Add it to a package. for example I add 
                  the interceptor at top of struts default stack >
       <interceptor-stack name="myDefaultStack">
          <interceptor-ref name="custInterceptor"/>
          <interceptor-ref name="defaultStack"/>
       </interceptor-stack>    
    
      <!  Use the interceptor stack in your action with @InterceptorRef or set it as default  >
      <default-interceptor-ref name="myDefaultStack" />
    
     </package>
    </struts>
    

    您可以看到默认的struts。xml https://struts.apache.org/docs/struts-defaultxml.html是如何定义和使用拦截器的好例子