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Struts2的使用注解配置Action（零配置）

由 心已入冬 提交于 2021-02-15 07:20:04

 

 

1.首先引入struts2注解的jar包：struts2-convention-plugin.jar

 

------------------------------第一种方式-------------------------------------

2.struts的配置

<?xml version="1.0" encoding="UTF-8" ?>
<!DOCTYPE struts PUBLIC
    "-//Apache Software Foundation//DTD Struts Configuration 2.3//EN"
    "http://struts.apache.org/dtds/struts-2.3.dtd">

<struts>
    <package name="lxyPackage" extends="json-default" namespace="/">
        
        <!-- S   QLQ 增加的培训类别管理 -->
        <global-results>
            <result name="success" type="json">
                <param name="root">response</param>
            </result>
        </global-results>
</struts>

 

 

3.TestAnnotationAction.java(测试JSON，跳转，重定向三种方式)

package cn.xm.exam.action.trainContent;

import java.util.HashMap;
import java.util.Map;

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 org.springframework.context.annotation.Scope;
import org.springframework.stereotype.Controller;

import com.opensymphony.xwork2.ActionSupport;

@Controller
@Scope("prototype") // 多例
@Namespace("/")
@Results({ @Result(name = "tiaozhuan", location = "/view/testPerson/outEmployeeAllot.jsp"),
        @Result(name = "redirect", type = "redirect", location = "/view/testPerson/outEmployeeAllot.jsp") })
@ParentPackage("lxyPackage") // 属于哪个package
public class TestAnnotationAction extends ActionSupport {
    private Map response;

    @Action("/test1")
    public String test1() {
        response = new HashMap();
        response.put("hello", "hello");
        return SUCCESS;
    }

    @Action("/test2")
    public String test2() {
        return "tiaozhuan";
    }

    @Action("/test3")
    public String test3() {
        return "redirect";
    }

    public Map getResponse() {
        return response;
    }

    public void setResponse(Map response) {
        this.response = response;
    }

}

 

 

4.测试:

(1)测试返回JSON

 

 

(2)测试转发

 

 

 

 (3)测试重定向

访问:　　http://localhost/Exam/test3.action

 

 

 

 

------------------------------第二种方式(注解返回JSON、跳转、重定向)-------------------------------------

pom.xml依赖:

<dependency>
            <groupId>org.apache.struts</groupId>
            <artifactId>struts2-convention-plugin</artifactId>
            <version>2.3.24</version>
        </dependency>
        <dependency>
            <groupId>org.apache.struts</groupId>
            <artifactId>struts2-core</artifactId>
            <version>2.3.24</version>
        </dependency>
        <dependency>
            <groupId>org.apache.struts</groupId>
            <artifactId>struts2-json-plugin</artifactId>
            <version>2.3.24</version>
        </dependency>

 

struts.xml配置

<?xml version="1.0" encoding="UTF-8" ?>
<!DOCTYPE struts PUBLIC
    "-//Apache Software Foundation//DTD Struts Configuration 2.3//EN"
    "http://struts.apache.org/dtds/struts-2.3.dtd">

<struts>
    <constant name="struts.i18n.encoding" value="utf-8"></constant>
    <constant name="devMode" value="true"></constant>
    <constant name="struts.enable.DynamicMethodInvocation" value="true" />
    <!-- 配置拦截的后缀 -->
    <constant name="struts.action.extension" value="action,do" />
    
    <package name="default" extends="json-default"></package>
    

</struts>

 

 

测试代码:

package cn.qlq.action;

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 com.opensymphony.xwork2.ActionSupport;
import com.opensymphony.xwork2.Preparable;

@Namespace("/")
@ParentPackage("default")
public class FirstAction extends ActionSupport implements Preparable {

    private static final long serialVersionUID = 1L;
    private String test;
    @Override
    public void prepare() throws Exception {
        System.out.println("这是所有方法前的处理");
    }

    @Action(value = "test", 
            results = { @Result(name = "success1", location = "/index2.jsp", type = "redirect") ,
                        @Result(name = "error", location = "/index2.jsp") ,
                        @Result(name = "success" ,type = "json" , params = {"root","test"}) 
                        })
    @Override
    public String execute() throws Exception {
        test = "test";
        return super.execute();
    }

    public String getTest() {
        return test;
    }

    public void setTest(String test) {
        this.test = test;
    }

    
}

 

注意:

　　@Result的type值默认为dispatcher(转发)。

　　如果普通页面跳转和重定向，不需要指定ParentPackage属性。

　　如果需要返回JSON，需要指定ParentPackage属性，否则找不到JSON结果类型，params = {"root","test"}是将test属性作为JSON返回前台，如果不指定参数会将所有带get、set的属性以JSON形式返回前台。

　　如果希望某些属性不被转为JSON返回前台，可以:

@JSON(serialize=false)//不被序列化 　

 

　

 补充:

　　网上说注解配置必须继承ActionSupport，经过测试不继承ActionSupport也是可以的。上面的是单独的没和spring整合的注解配置，发现是多例模式，每次请求都会创建Action对象。

 

 

------------------------------第三种:和spring整合的注解----------------

pom配置:

 

<project xmlns="http://maven.apache.org/POM/4.0.0" xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"
    xsi:schemaLocation="http://maven.apache.org/POM/4.0.0 http://maven.apache.org/maven-v4_0_0.xsd">
    <modelVersion>4.0.0</modelVersion>
    <groupId>cn.xm</groupId>
    <artifactId>jwxt</artifactId>
    <packaging>war</packaging>
    <version>1.0-SNAPSHOT</version>
    <name>jwxt Maven Webapp</name>
    <url>http://maven.apache.org</url>

    <dependencies>
        <dependency>
            <groupId>junit</groupId>
            <artifactId>junit</artifactId>
            <version>4.9</version>
        </dependency>
        <dependency>
            <groupId>javax.servlet</groupId>
            <artifactId>servlet-api</artifactId>
            <version>2.5</version>
            <scope>provided</scope>
        </dependency>
        <dependency>
            <groupId>javax.servlet</groupId>
            <artifactId>jsp-api</artifactId>
            <version>2.0</version>
            <scope>provided</scope>
        </dependency>

        <!-- 调试过程中自己加的包依赖包 -->
        <dependency>
            <groupId>org.apache.logging.log4j</groupId>
            <artifactId>log4j-api</artifactId>
            <version>2.0-rc1</version>
        </dependency>

        <dependency>
            <groupId>org.apache.logging.log4j</groupId>
            <artifactId>log4j-core</artifactId>
            <version>2.0-rc1</version>
        </dependency>

        <!--EL和JSTL -->
        <dependency>
            <groupId>taglibs</groupId>
            <artifactId>standard</artifactId>
            <version>1.1.2</version>
        </dependency>
        <dependency>
            <groupId>javax.servlet</groupId>
            <artifactId>jstl</artifactId>
            <version>1.2</version>
        </dependency>


        <dependency>
            <groupId>org.apache.struts</groupId>
            <artifactId>struts2-convention-plugin</artifactId>
            <version>2.3.24</version>
        </dependency>
        <dependency>
            <groupId>org.apache.struts</groupId>
            <artifactId>struts2-core</artifactId>
            <version>2.3.24</version>
        </dependency>
        <dependency>
            <groupId>org.apache.struts</groupId>
            <artifactId>struts2-json-plugin</artifactId>
            <version>2.3.24</version>
        </dependency>
        <!-- slf4j 依赖包 -->
        <dependency>
            <groupId>org.slf4j</groupId>
            <artifactId>slf4j-api</artifactId>
            <version>1.7.25</version>
        </dependency>
        <dependency>
            <groupId>org.slf4j</groupId>
            <artifactId>slf4j-log4j12</artifactId>
            <version>1.7.5</version>
        </dependency>
        <dependency>
            <groupId>org.apache.logging.log4j</groupId>
            <artifactId>log4j-api</artifactId>
            <version>2.0-rc1</version>
        </dependency>
        <dependency>
            <groupId>org.apache.logging.log4j</groupId>
            <artifactId>log4j-core</artifactId>
            <version>2.0-rc1</version>
        </dependency>
        <dependency>
            <groupId>org.apache.struts</groupId>
            <artifactId>struts2-spring-plugin</artifactId>
            <version>2.3.24</version>
        </dependency>
    </dependencies>

    <build>
        <!-- 配置了很多插件 -->
        <plugins>

            <!-- 编译插件 -->
            <plugin>
                <groupId>org.apache.maven.plugins</groupId>
                <artifactId>maven-compiler-plugin</artifactId>
                <version>3.5.1</version>
                <configuration>
                    <source>1.7</source>
                    <target>1.7</target>
                    <encoding>UTF-8</encoding>
                </configuration>
            </plugin>
        </plugins>
    </build>
</project>

 

 

 

spring配置:

<?xml version="1.0" encoding="UTF-8"?>
<beans xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"
    xmlns="http://www.springframework.org/schema/beans" xmlns:context="http://www.springframework.org/schema/context"
    xmlns:aop="http://www.springframework.org/schema/aop" xmlns:tx="http://www.springframework.org/schema/tx"
    xsi:schemaLocation="http://www.springframework.org/schema/beans http://www.springframework.org/schema/beans/spring-beans-3.2.xsd http://www.springframework.org/schema/context http://www.springframework.org/schema/context/spring-context-3.2.xsd http://www.springframework.org/schema/aop http://www.springframework.org/schema/aop/spring-aop-3.2.xsd http://www.springframework.org/schema/tx http://www.springframework.org/schema/tx/spring-tx-3.2.xsd ">
    
    <!-- 扫描Action基本包 -->
    <context:component-scan base-package="cn.qlq.action"></context:component-scan>
    
</beans>

 

 

struts配置:

<?xml version="1.0" encoding="UTF-8" ?>
<!DOCTYPE struts PUBLIC
    "-//Apache Software Foundation//DTD Struts Configuration 2.3//EN"
    "http://struts.apache.org/dtds/struts-2.3.dtd">

<struts>
    <constant name="struts.i18n.encoding" value="utf-8"></constant>
    <constant name="devMode" value="true"></constant>
    <constant name="struts.enable.DynamicMethodInvocation" value="true" />
    <constant name="" value="true" />
    <!-- 配置拦截的后缀 -->
    <constant name="struts.action.extension" value="action,do" />
    <!-- 与spring整合 -->
    <constant name="struts.objectFactory" value="spring"></constant>
    <package name="default" extends="json-default"></package>
    

</struts>

 

 

web.xml配置:

<?xml version="1.0" encoding="UTF-8"?>
<web-app xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"
    xmlns="http://java.sun.com/xml/ns/javaee"
    xsi:schemaLocation="http://java.sun.com/xml/ns/javaee http://java.sun.com/xml/ns/javaee/web-app_2_5.xsd"
    id="WebApp_ID" version="2.5">
    <display-name>Struts</display-name>
    <welcome-file-list>
        <welcome-file>index.jsp</welcome-file>
    </welcome-file-list>

    <!-- spring -->
    <listener>
        <listener-class>org.springframework.web.context.ContextLoaderListener</listener-class>
    </listener>
    <context-param>
        <param-name>contextConfigLocation</param-name>
        <param-value>classpath:applicationContext.xml</param-value>
    </context-param>

    <!-- struts -->
    <filter>
        <filter-name>struts2</filter-name>
        <filter-class>org.apache.struts2.dispatcher.ng.filter.StrutsPrepareAndExecuteFilter</filter-class>
    </filter>
    <filter-mapping>
        <filter-name>struts2</filter-name>
        <url-pattern>/*</url-pattern>
    </filter-mapping>

</web-app>

 

 

测试:

package cn.qlq.action;

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.springframework.context.annotation.Scope;
import org.springframework.stereotype.Controller;

import com.opensymphony.xwork2.ActionSupport;

@Namespace("/")
@ParentPackage("default")
@Controller("firstAction")
@Scope("singleton")
public class FirstAction extends ActionSupport{

    private String test;
    
    public FirstAction() {
        System.out.println("-----------无参构造方法---------");
    }

    @Action(value = "test", results = { @Result(name = "success1", location = "/index2.jsp", type = "redirect"),
            @Result(name = "error", location = "/index2.jsp"),
            @Result(name = "success", type = "json", params = { "root", "test" }) })
    public String execute() throws Exception {
        test = "test";
        return "success";
    }

    public String getTest() {
        return test;
    }

    public void setTest(String test) {
        this.test = test;
    }

}

 

 

发现上面无论我们写不写@Controller都可以生成Action对象，写不写scope都是多例模式，即使写成单例也是多例。

 

 

 

补充:有时候我们希望简化配置，不想每个方法都写一对Action注解，如下:(先结果写在类注解上，然后每个方法只写对应的Action的value即可)

package cn.qlq.action;

import java.util.HashMap;
import java.util.Map;

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 org.springframework.stereotype.Controller;

import com.opensymphony.xwork2.ActionSupport;

@Namespace("/")
@ParentPackage("default")
@Controller("firstAction")
@Results({ @Result(name = "redirect", location = "/index2.jsp", type = "redirect"),
        @Result(name = "forward", location = "/index.jsp"),
        @Result(name = "json", type = "json", params = { "root", "responseMap" }) })
public class FirstAction extends ActionSupport {

    private Map<String, Object> responseMap = new HashMap<String, Object>();

    public FirstAction() {
        System.out.println("-----------无参构造方法---------");
    }

    @Action(value = "getJson1")
    public String getJson1() {
        try {
            Thread.sleep(2 * 1000);
        } catch (InterruptedException e) {
            // TODO Auto-generated catch block
            e.printStackTrace();
        }
        responseMap.put("str1", "str1");
        return "json";
    }

    @Action(value = "getJson2")
    public String getJson2() {
        try {
            Thread.sleep(2 * 1000);
        } catch (InterruptedException e) {
            // TODO Auto-generated catch block
            e.printStackTrace();
        }
        responseMap.put("str2", "str2");
        return "json";
    }

    @Action(value = "redirect")
    public String redirect() {
        try {
            Thread.sleep(2 * 1000);
        } catch (InterruptedException e) {
            e.printStackTrace();
        }
        responseMap.put("redirect", "redirect");
        return "redirect";
    }

    @Action(value = "forward")
    public String forward() {
        try {
            Thread.sleep(2 * 1000);
        } catch (InterruptedException e) {
            // TODO Auto-generated catch block
            e.printStackTrace();
        }
        responseMap.put("forward", "forward");
        return "forward";
    }

    public Map<String, Object> getResponseMap() {
        return responseMap;
    }

    public void setResponseMap(Map<String, Object> responseMap) {
        this.responseMap = responseMap;
    }

}

 

结果:

 

 

 

 

 

 

 

 

控制台:(证明Action是多例的，每个请求都会创建新的Action)

 

 

 

有时候我们也希望方法上的注解覆盖类上的注解，例如:

package cn.qlq.action;

import java.util.HashMap;
import java.util.Map;

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 org.springframework.stereotype.Controller;

import com.opensymphony.xwork2.ActionSupport;

@Namespace("/")
@ParentPackage("default")
@Controller("firstAction")
@Results({ @Result(name = "redirect", location = "/index2.jsp", type = "redirect"),
        @Result(name = "forward", location = "/index.jsp"),
        @Result(name = "json", type = "json", params = { "root", "responseMap" }) })
public class FirstAction extends ActionSupport {

    private Map<String, Object> responseMap = new HashMap<String, Object>();

    public FirstAction() {
        System.out.println("-----------无参构造方法---------");
    }

    @Action(value = "getJson1")
    public String getJson1() {
        try {
            Thread.sleep(2 * 1000);
        } catch (InterruptedException e) {
            // TODO Auto-generated catch block
            e.printStackTrace();
        }
        responseMap.put("str1", "str1");
        return "json";
    }

    @Action(value = "getJson2")
    public String getJson2() {
        try {
            Thread.sleep(2 * 1000);
        } catch (InterruptedException e) {
            // TODO Auto-generated catch block
            e.printStackTrace();
        }
        responseMap.put("str2", "str2");
        return "json";
    }

    // 希望返回是json的时候还是页面跳转
    @Action(value = "getJson3", results = { @Result(name = "json", location = "/index.jsp") })
    public String getJson3() {
        try {
            Thread.sleep(2 * 1000);
        } catch (InterruptedException e) {
            e.printStackTrace();
        }
        responseMap.put("str3", "str3");
        return "json";
    }

    @Action(value = "redirect")
    public String redirect() {
        try {
            Thread.sleep(2 * 1000);
        } catch (InterruptedException e) {
            e.printStackTrace();
        }
        responseMap.put("redirect", "redirect");
        return "redirect";
    }

    @Action(value = "forward")
    public String forward() {
        try {
            Thread.sleep(2 * 1000);
        } catch (InterruptedException e) {
            // TODO Auto-generated catch block
            e.printStackTrace();
        }
        responseMap.put("forward", "forward");
        return "forward";
    }

    public Map<String, Object> getResponseMap() {
        return responseMap;
    }

    public void setResponseMap(Map<String, Object> responseMap) {
        this.responseMap = responseMap;
    }

}

测试:

 

总结:方法上的结果返回的定义优先级别高于类级别的返回结果定义，所以我们可以在配置中采用此方式简化一些配置。 

 

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