Spring@JsonIgnore不工作

Question

我怎么才能让@JsonIgnore工作呢？我有课。即使我把注释放在那里，它对输出也没有影响。我在用杰克逊。

public class QuestionBlock implements ComparableByID{


    int ID;

    String title;
    String description;
    boolean deleted;
    boolean isDraft;
    boolean visible;
    Timestamp modifiedDate;
    String modifiedBy;


    private List<Question> questions =  new ArrayList<>();

    @JsonIgnore
    private List<Survey> surveys =  new ArrayList<>();

    ...

    @JsonIgnore
    public List<Survey> getSurveys() {
        return surveys;
    }

    @JsonIgnore
    public void setSurveys(List<Survey> surveys) {
        this.surveys = surveys;
    }

}

这是我的控制器方法：

@RequestMapping(value = "/questionBlock/{id}",produces = "application/json;charset=UTF-8")
    @ResponseBody
    public QuestionBlock getQuestionBlock(@PathVariable("id") int id) {
        return surveyService.getQuestionBlock(id);
    }

这是我的servlet-context.xml：

<?xml version="1.0" encoding="UTF-8"?>
<beans xmlns="http://www.springframework.org/schema/beans"
    xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance" xmlns:mvc="http://www.springframework.org/schema/mvc"
    xmlns:beans="http://www.springframework.org/schema/beans"
    xmlns:context="http://www.springframework.org/schema/context" xmlns:tx="http://www.springframework.org/schema/tx"
    xsi:schemaLocation="http://www.springframework.org/schema/mvc http://www.springframework.org/schema/mvc/spring-mvc-3.2.xsd
    http://www.springframework.org/schema/beans http://www.springframework.org/schema/beans/spring-beans.xsd
    http://www.springframework.org/schema/tx http://www.springframework.org/schema/tx/spring-tx-3.2.xsd
    http://www.springframework.org/schema/context http://www.springframework.org/schema/context/spring-context-3.2.xsd">

    <mvc:annotation-driven />


    <mvc:resources mapping="/resources/**" location="/resources/" />
    <mvc:resources location="/, classpath:/META-INF/web-resources/"
        mapping="/resources/**" />

    <context:property-placeholder location="classpath*:META-INF/*.properties" />


    <context:component-scan base-package="com.adam.czibere" />



    <bean class="org.apache.commons.dbcp.BasicDataSource" destroy-method="close" id="myDataSource" name="dataSource">
        <property name="driverClassName" value="${database.driverClassName}" />
        <property name="url" value="${database.url}" />
        <property name="username" value="${database.username}" />
        <property name="password" value="${database.password}" />
        <property name="testOnBorrow" value="true" />
        <property name="testOnReturn" value="true" />
        <property name="testWhileIdle" value="true" />
        <property name="timeBetweenEvictionRunsMillis" value="1800000" />
        <property name="numTestsPerEvictionRun" value="3" />
        <property name="minEvictableIdleTimeMillis" value="1800000" />
        <property name="validationQuery" value="SELECT 1" />
    </bean>


    <bean id="mySessionFactory"
        class="org.springframework.orm.hibernate4.LocalSessionFactoryBean">
        <property name="dataSource" ref="myDataSource" />
        <property name="packagesToScan">
            <array>
                <value>com.adam.czibere</value>
            </array>
        </property>
        <property name="hibernateProperties">
            <value>
                hibernate.dialect=org.hibernate.dialect.MySQLDialect
            </value>
        </property>
    </bean>

    <bean id="transactionManager"
        class="org.springframework.orm.hibernate4.HibernateTransactionManager">
        <property name="sessionFactory" ref="mySessionFactory" />
    </bean>


    <tx:annotation-driven transaction-manager="transactionManager"/>

<bean
        class="org.springframework.web.servlet.view.ContentNegotiatingViewResolver">
        <property name="mediaTypes">
            <map>
                <entry key="html" value="text/html" />
                <entry key="json" value="application/json" />
            </map>
        </property>
        <property name="viewResolvers">
            <list>
                <bean
                    class="org.springframework.web.servlet.view.InternalResourceViewResolver">
                    <property name="prefix" value="/WEB-INF/views/" />
                    <property name="suffix" value=".jsp" />
                </bean>
            </list>
        </property>
        <property name="defaultViews">
            <list>
                <bean
                    class="org.springframework.web.servlet.view.json.MappingJacksonJsonView">
                    <property name="prefixJson" value="false" />
                    <property name="objectMapper" ref="jacksonObjectMapper" />
                </bean>
            </list>
        </property>
    </bean>
    <bean id="jacksonObjectMapper" class="org.codehaus.jackson.map.ObjectMapper" />
    <bean
        class="org.springframework.web.servlet.mvc.annotation.AnnotationMethodHandlerAdapter">
        <property name="messageConverters">
            <list>
                <bean
                    class="org.springframework.http.converter.json.MappingJacksonHttpMessageConverter">
                    <property name="prefixJson" value="false" />
                    <property name="supportedMediaTypes" value="application/json" />
                </bean>
            </list>
        </property>
    </bean>
</beans>

Answer 1

如果您使用的是Jackson的一个实现，而它的注释不起作用，这可能是因为您对Jackson的另一个依赖项具有更好的优先级。因此，如果您想确保jackson prevales的某些实现（IMHO最佳选择是所有类都已注释的实现，因为它可能附带其他依赖项），请在应用程序模块的pom中指定此依赖项。所以如果你在多个模块中有所有的实体

import com.fasterxml.jackson.annotate.JsonIgnore;  // note: com. instead of org.

不替换所有导入，只需在应用程序pom中指定相应的依赖项：

    <dependency>
        <groupId>com.fasterxml.jackson.core</groupId>
        <artifactId>jackson-databind</artifactId>
    </dependency>

这将向Spring Boot澄清这是您要使用的实现。

Answer 2

注释应该只在“get”方法上。你似乎有@Json。。。私人字段上的注释。

Answer 3

我终于找到了解决办法。我把进口声明从

import com.fasterxml.jackson.annotate.JsonIgnore;  // com. instead of org.

到

import org.codehaus.jackson.annotate.JsonIgnore;

基本上，你必须确保你在任何地方都使用相同的类。