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JQuery,Spring MVC @RequestBody和JSON--使它們一起工作 (4)

我想要一個雙向的JSON到Java序列化

我正在成功使用Java to JSON to JQuery path ...( @ResponseBody )例如

@RequestMapping(value={"/fooBar/{id}"}, method=RequestMethod.GET)
     public @ResponseBody FooBar getFooBar(
            @PathVariable String id,
            HttpServletResponse response , ModelMap model) {
        response.setContentType("application/json");
...
}

和我在使用JQuery

$.getJSON('fooBar/1', function(data) {
    //do something
});

很有效 (例如註釋已經工作,這要感謝所有的答复者)

但是,如何做相反的路徑:使用RequestBody將JSON序列化為Java對象?

無論我嘗試什麼,我都無法得到像這樣的工作:

@RequestMapping(value={"/fooBar/save"}, method=RequestMethod.POST)
public String saveFooBar(@RequestBody FooBar fooBar,
        HttpServletResponse response , ModelMap model) {

  //This method is never called. (it does when I remove the RequestBody...)
}

我有傑克遜配置正確(它在出路序列化),我有MVC設置為註釋驅動當然

我如何使它工作? 有沒有可能? 或者是Spring / JSON / JQuery是單向的(out)?

更新:

我改變了這個傑克遜設置

<bean id="jsonHttpMessageConverter"
    class="org.springframework.http.converter.json.MappingJacksonHttpMessageConverter" />

<!-- Bind the return value of the Rest service to the ResponseBody. -->
<bean
    class="org.springframework.web.servlet.mvc.annotation.AnnotationMethodHandlerAdapter">
    <property name="messageConverters">
        <util:list id="beanList">
            <ref bean="jsonHttpMessageConverter" />
<!--            <ref bean="xmlMessageConverter" /> -->              
        </util:list>
    </property>
</bean>

到(幾乎類似的)建議

<bean id="jacksonMessageConverter"
    class="org.springframework.http.converter.json.MappingJacksonHttpMessageConverter"></bean>
    <bean
        class="org.springframework.web.servlet.mvc.annotation.AnnotationMethodHandlerAdapter">
        <property name="messageConverters">
            <list>
                <ref bean="jacksonMessageConverter" />
            </list>
        </property>
    </bean> 

它似乎工作! 我不知道這個訣竅究竟是什麼,但它的工作原理是......


另外你還需要確定你有

 <context:annotation-config/> 

在您的SPring配置xml中。

我也會建議你閱讀這篇博文。 這對我幫助很大。 Spring博客 - Spring 3.0中的Ajax簡化

更新:

只是檢查我的工作代碼,我有@RequestBody工作正常。 我的配置中也有這個bean:

<bean id="jacksonMessageConverter" class="org.springframework.http.converter.json.MappingJacksonHttpMessageConverter"></bean>
 <bean class="org.springframework.web.servlet.mvc.annotation.AnnotationMethodHandlerAdapter">
<property name="messageConverters">
  <list>
    <ref bean="jacksonMessageConverter"/>
  </list>
</property>
</bean>

可能會很高興看到Log4j在說什麼。 它通常會提供更多信息,根據我的經驗,如果請求的內容類型不是Application/JSON@RequestBody將失敗。 您可以運行Fiddler 2來測試它,甚至Mozilla Live HTTP頭插件也可以提供幫助。


如果你不想自己配置消息轉換器,你可以使用@EnableWebMvc或<mvc:annotation-driven /> ,將Jackson添加到類路徑中,Spring將為你提供JSON,XML(以及其他一些轉換器)默認。 此外,您還將獲得其他一些常用的轉換,格式和驗證功能。


我很確定你只需要註冊MappingJacksonHttpMessageConverter

(最簡單的方法是通過XML中的<mvc:annotation-driven />或Java中的@EnableWebMvc

看到:

這是一個工作示例:

Maven POM

<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>test</groupId><artifactId>json</artifactId><packaging>war</packaging>
    <version>0.0.1-SNAPSHOT</version><name>json test</name>
    <dependencies>
        <dependency><!-- spring mvc -->
            <groupId>org.springframework</groupId><artifactId>spring-webmvc</artifactId><version>3.0.5.RELEASE</version>
        </dependency>
        <dependency><!-- jackson -->
            <groupId>org.codehaus.jackson</groupId><artifactId>jackson-mapper-asl</artifactId><version>1.4.2</version>
        </dependency>
    </dependencies>
    <build><plugins>
            <!-- javac --><plugin><groupId>org.apache.maven.plugins</groupId><artifactId>maven-compiler-plugin</artifactId>
            <version>2.3.2</version><configuration><source>1.6</source><target>1.6</target></configuration></plugin>
            <!-- jetty --><plugin><groupId>org.mortbay.jetty</groupId><artifactId>jetty-maven-plugin</artifactId>
            <version>7.4.0.v20110414</version></plugin>
    </plugins></build>
</project>

在文件夾src / main / webapp / WEB-INF中

web.xml中

<web-app xmlns="http://java.sun.com/xml/ns/j2ee" xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"
    xsi:schemaLocation="http://java.sun.com/xml/ns/j2ee http://java.sun.com/xml/ns/j2ee/web-app_2_4.xsd"
    version="2.4">
    <servlet><servlet-name>json</servlet-name>
        <servlet-class>org.springframework.web.servlet.DispatcherServlet</servlet-class>
        <load-on-startup>1</load-on-startup>
    </servlet>
    <servlet-mapping>
        <servlet-name>json</servlet-name>
        <url-pattern>/*</url-pattern>
    </servlet-mapping>
</web-app>

JSON-servlet.xml中

<beans xmlns="http://www.springframework.org/schema/beans"
    xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"
    xsi:schemaLocation="http://www.springframework.org/schema/beans
                        http://www.springframework.org/schema/beans/spring-beans.xsd">

    <import resource="classpath:mvc-context.xml" />

</beans>

在文件夾src / main / resources中:

MVC-的context.xml

<beans xmlns="http://www.springframework.org/schema/beans"
    xmlns:mvc="http://www.springframework.org/schema/mvc" xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"
    xmlns:context="http://www.springframework.org/schema/context"
    xsi:schemaLocation="http://www.springframework.org/schema/mvc http://www.springframework.org/schema/mvc/spring-mvc-3.0.xsd
        http://www.springframework.org/schema/beans http://www.springframework.org/schema/beans/spring-beans-3.0.xsd
        http://www.springframework.org/schema/context http://www.springframework.org/schema/context/spring-context-3.0.xsd">

    <mvc:annotation-driven />
    <context:component-scan base-package="test.json" />
</beans>

在文件夾src / main / java / test / json中

TestController.java

@Controller
@RequestMapping("/test")
public class TestController {

    @RequestMapping(method = RequestMethod.POST, value = "math")
    @ResponseBody
    public Result math(@RequestBody final Request request) {
        final Result result = new Result();
        result.setAddition(request.getLeft() + request.getRight());
        result.setSubtraction(request.getLeft() - request.getRight());
        result.setMultiplication(request.getLeft() * request.getRight());
        return result;
    }

}

Request.java

public class Request implements Serializable {
    private static final long serialVersionUID = 1513207428686438208L;
    private int left;
    private int right;
    public int getLeft() {return left;}
    public void setLeft(int left) {this.left = left;}
    public int getRight() {return right;}
    public void setRight(int right) {this.right = right;}
}

Result.java

public class Result implements Serializable {
    private static final long serialVersionUID = -5054749880960511861L;
    private int addition;
    private int subtraction;
    private int multiplication;

    public int getAddition() { return addition; }
    public void setAddition(int addition) { this.addition = addition; }
    public int getSubtraction() { return subtraction; }
    public void setSubtraction(int subtraction) { this.subtraction = subtraction; }
    public int getMultiplication() { return multiplication; }
    public void setMultiplication(int multiplication) { this.multiplication = multiplication; }
}

您可以通過執行mvn jetty:run來測試此設置mvn jetty:run在命令行上mvn jetty:run ,然後發送POST請求:

URL:        http://localhost:8080/test/math
mime type:  application/json
post body:  { "left": 13 , "right" : 7 }

我使用海報Firefox插件來做到這一點。

以下是響應的內容:

{"addition":20,"subtraction":6,"multiplication":91}

除了這裡的答案...

如果你在客戶端使用jQuery,這對我有用:

Java的:

@RequestMapping(value = "/ajax/search/sync") 
public String sync(@RequestBody Foo json) {

Jquery(您需要包含Douglas Crockford的json2.js才能擁有JSON.stringify函數):

$.ajax({
    type: "post",
    url: "sync", //your valid url
    contentType: "application/json", //this is required for spring 3 - ajax to work (at least for me)
    data: JSON.stringify(jsonobject), //json object or array of json objects
    success: function(result) {
        //do nothing
    },
    error: function(){
        alert('failure');
    }
});




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