Jackson 反序列化：@JsonAlias 不起作用

Question

I try to fill up an Java Object with a Json String, which can come with different kinds of variable names for the same field. That's why I try to use @JsonAlias. Unfortunately, I couldn't make it work yet for unknown reasons..

Here is my example:

The Java Object:

import com.fasterxml.jackson.annotation.JsonAlias;

public class ExampleClass {

    @JsonAlias({"test_1", "1"})
    private String test1;

    @JsonAlias({"test_2", "2"})
    private String test2;

    public String getTest1() {
        return test1;
    }

    public void setTest1(String test1) {
        this.test1 = test1;
    }

    public String getTest2() {
        return test2;
    }

    public void setTest2(String test2) {
        this.test2 = test2;
    }
}

The Json, I try to deserialize:

ObjectMapper mapper = new ObjectMapper();

ExampleClass javaObject = mapper.readerFor(ExampleClass.class).readValue("{\"test_1\": \"heyo\", \"test_2\":  \"heyo2\" }");

With "test_1" defined in the @JsonAlias Annotation above the field "test1", Jackson should find and fill up the field. But I get instead this following error:

17:02:34,653 ERROR [stderr] (default task-3) com.fasterxml.jackson.databind.exc.UnrecognizedPropertyException: Unrecognized field "test_1" (class ch.ejb.ExampleClass), not marked as ignorable (2 known properties: "test2", "test1"])

edit: My Maven dependencies:

        <dependencies>

            <dependency>
                <groupId>org.apache.maven.plugins</groupId>
                <artifactId>maven-war-plugin</artifactId>
                <version>3.3.2</version>
            </dependency>
            <dependency><!-- add slf4j VYTH -->
                <groupId>org.slf4j</groupId>
                <artifactId>slf4j-simple</artifactId>
                <version>1.7.9</version>
                <scope>provided</scope>
            </dependency>
            <dependency>
                <groupId>org.apache.poi</groupId>
                <artifactId>poi</artifactId>
                <version>3.9</version>
            </dependency>
            <dependency>
                <groupId>org.hibernate</groupId>
                <artifactId>hibernate-entitymanager</artifactId>
                <version>3.6.0.Final</version>

            </dependency>
            <dependency>
                <groupId>com.itextpdf</groupId>
                <artifactId>itextpdf</artifactId>
                <version>5.5.7</version>
            </dependency>
            <dependency>
                <groupId>org.freemarker</groupId>
                <artifactId>freemarker</artifactId>
                <version>2.3.23</version>
            </dependency>
            <dependency>
                <groupId>com.itextpdf.tool</groupId>
                <artifactId>xmlworker</artifactId>
                <version>5.5.7</version>
            </dependency>
            <dependency>
                <groupId>javax.ejb</groupId>
                <artifactId>javax.ejb-api</artifactId>
                <version>3.2.2</version>
            </dependency>
            <dependency>
                <groupId>javax.ws.rs</groupId>
                <artifactId>javax.ws.rs-api</artifactId>
                <version>2.0</version>
            </dependency>
            <dependency>
                <groupId>org.jboss.resteasy</groupId>
                <artifactId>resteasy-jaxrs</artifactId>
                <version>3.0.19.Final</version>
            </dependency>
            <dependency>
                <groupId>io.jsonwebtoken</groupId>
                <artifactId>jjwt</artifactId>
                <version>0.9.1</version>
                <exclusions>
                    <exclusion>
                        <groupId>com.fasterxml.jackson.core</groupId>
                        <artifactId>jackson-databind</artifactId>
                    </exclusion>
                </exclusions>
            </dependency>

            <dependency>
                <groupId>org.apache.commons</groupId>
                <artifactId>commons-text</artifactId>
                <version>1.9</version>
            </dependency>
            <dependency>
                <groupId>javax.servlet</groupId>
                <artifactId>javax.servlet-api</artifactId>
                <version>3.0.1</version>
                <scope>provided</scope>
            </dependency>
            <dependency>
                <groupId>com.google.code.gson</groupId>
                <artifactId>gson</artifactId>
                <version>2.8.7</version>
            </dependency>
            <dependency>
                <groupId>com.fasterxml.jackson.core</groupId>
                <artifactId>jackson-databind</artifactId>
                <version>2.12.0</version>
            </dependency>
            <dependency>
                <groupId>io.swagger.core.v3</groupId>
                <artifactId>swagger-jaxrs2</artifactId>
                <scope>compile</scope>
                <version>2.0.10</version>
            </dependency>
            <dependency>
                <groupId>io.swagger.core.v3</groupId>
                <artifactId>swagger-annotations</artifactId>
                <version>2.0.10</version>
            </dependency>
            <dependency>
                <groupId>org.webjars</groupId>
                <artifactId>swagger-ui</artifactId>
                <version>2.1.4</version>
            </dependency>
            <dependency>
                <groupId>com.squareup.okhttp3</groupId>
                <artifactId>okhttp</artifactId>
                <version>4.9.1</version>
            </dependency>
            <dependency>
                <groupId>org.apache.commons</groupId>
                <artifactId>commons-lang3</artifactId>
                <version>3.12.0</version>
            </dependency>
        </dependencies>

The error code:

13:36:10,858 ERROR [stderr] (default task-6) com.fasterxml.jackson.databind.exc.UnrecognizedPropertyException: Unrecognized field "test_1" (class ch.rest.opk.ExampleClass), not marked as ignorable (2 known properties: "test2", "test1"])
13:36:10,859 ERROR [stderr] (default task-6)  at [Source: {"test_1": "heyo", "test_2":  "heyo2" }; line: 1, column: 13] (through reference chain: ch.rest.opk.ExampleClass["test_1"])
13:36:10,860 ERROR [stderr] (default task-6)    at com.fasterxml.jackson.core.jackson-databind//com.fasterxml.jackson.databind.exc.UnrecognizedPropertyException.from(UnrecognizedPropertyException.java:63)
13:36:10,861 ERROR [stderr] (default task-6)    at com.fasterxml.jackson.core.jackson-databind//com.fasterxml.jackson.databind.DeserializationContext.handleUnknownProperty(DeserializationContext.java:834)
13:36:10,862 ERROR [stderr] (default task-6)    at com.fasterxml.jackson.core.jackson-databind//com.fasterxml.jackson.databind.deser.std.StdDeserializer.handleUnknownProperty(StdDeserializer.java:1093)
13:36:10,863 ERROR [stderr] (default task-6)    at com.fasterxml.jackson.core.jackson-databind//com.fasterxml.jackson.databind.deser.BeanDeserializerBase.handleUnknownProperty(BeanDeserializerBase.java:1489)
13:36:10,864 ERROR [stderr] (default task-6)    at com.fasterxml.jackson.core.jackson-databind//com.fasterxml.jackson.databind.deser.BeanDeserializerBase.handleUnknownVanilla(BeanDeserializerBase.java:1467)
13:36:10,865 ERROR [stderr] (default task-6)    at com.fasterxml.jackson.core.jackson-databind//com.fasterxml.jackson.databind.deser.BeanDeserializer.vanillaDeserialize(BeanDeserializer.java:282)
13:36:10,866 ERROR [stderr] (default task-6)    at com.fasterxml.jackson.core.jackson-databind//com.fasterxml.jackson.databind.deser.BeanDeserializer.deserialize(BeanDeserializer.java:140)
13:36:10,867 ERROR [stderr] (default task-6)    at com.fasterxml.jackson.core.jackson-databind//com.fasterxml.jackson.databind.ObjectReader._bindAndClose(ObjectReader.java:1626)
13:36:10,868 ERROR [stderr] (default task-6)    at com.fasterxml.jackson.core.jackson-databind//com.fasterxml.jackson.databind.ObjectReader.readValue(ObjectReader.java:1220)
13:36:10,869 ERROR [stderr] (default task-6)    at deployment.opk-backend.war//ch.rest.opk.LimitenServices.getLimitenExcel(LimitenServices.java:153)
13:36:10,870 ERROR [stderr] (default task-6)    at java.base/jdk.internal.reflect.NativeMethodAccessorImpl.invoke0(Native Method)
13:36:10,870 ERROR [stderr] (default task-6)    at java.base/jdk.internal.reflect.NativeMethodAccessorImpl.invoke(NativeMethodAccessorImpl.java:62)
13:36:10,871 ERROR [stderr] (default task-6)    at java.base/jdk.internal.reflect.DelegatingMethodAccessorImpl.invoke(DelegatingMethodAccessorImpl.java:43)
13:36:10,872 ERROR [stderr] (default task-6)    at java.base/java.lang.reflect.Method.invoke(Method.java:566)
13:36:10,873 ERROR [stderr] (default task-6)    at org.jboss.resteasy.resteasy-jaxrs//org.jboss.resteasy.core.MethodInjectorImpl.invoke(MethodInjectorImpl.java:140)
13:36:10,874 ERROR [stderr] (default task-6)    at org.jboss.resteasy.resteasy-jaxrs//org.jboss.resteasy.core.ResourceMethodInvoker.invokeOnTarget(ResourceMethodInvoker.java:295)
13:36:10,875 ERROR [stderr] (default task-6)    at org.jboss.resteasy.resteasy-jaxrs//org.jboss.resteasy.core.ResourceMethodInvoker.invoke(ResourceMethodInvoker.java:249)
13:36:10,876 ERROR [stderr] (default task-6)    at org.jboss.resteasy.resteasy-jaxrs//org.jboss.resteasy.core.ResourceMethodInvoker.invoke(ResourceMethodInvoker.java:236)
13:36:10,877 ERROR [stderr] (default task-6)    at org.jboss.resteasy.resteasy-jaxrs//org.jboss.resteasy.core.SynchronousDispatcher.invoke(SynchronousDispatcher.java:406)
13:36:10,879 ERROR [stderr] (default task-6)    at org.jboss.resteasy.resteasy-jaxrs//org.jboss.resteasy.core.SynchronousDispatcher.invoke(SynchronousDispatcher.java:213)
13:36:10,880 ERROR [stderr] (default task-6)    at org.jboss.resteasy.resteasy-jaxrs//org.jboss.resteasy.plugins.server.servlet.ServletContainerDispatcher.service(ServletContainerDispatcher.java:228)
13:36:10,882 ERROR [stderr] (default task-6)    at org.jboss.resteasy.resteasy-jaxrs//org.jboss.resteasy.plugins.server.servlet.HttpServletDispatcher.service(HttpServletDispatcher.java:56)
13:36:10,883 ERROR [stderr] (default task-6)    at org.jboss.resteasy.resteasy-jaxrs//org.jboss.resteasy.plugins.server.servlet.HttpServletDispatcher.service(HttpServletDispatcher.java:51)
13:36:10,884 ERROR [stderr] (default task-6)    at javax.servlet.api//javax.servlet.http.HttpServlet.service(HttpServlet.java:790)
13:36:10,885 ERROR [stderr] (default task-6)    at io.undertow.servlet//io.undertow.servlet.handlers.ServletHandler.handleRequest(ServletHandler.java:74)
13:36:10,886 ERROR [stderr] (default task-6)    at io.undertow.servlet//io.undertow.servlet.handlers.FilterHandler$FilterChainImpl.doFilter(FilterHandler.java:129)
13:36:10,887 ERROR [stderr] (default task-6)    at deployment.opk-backend.war//ch.rest.CorsResponseFilter.doFilter(CorsResponseFilter.java:56)
13:36:10,887 ERROR [stderr] (default task-6)    at io.undertow.servlet//io.undertow.servlet.core.ManagedFilter.doFilter(ManagedFilter.java:61)
13:36:10,888 ERROR [stderr] (default task-6)    at io.undertow.servlet//io.undertow.servlet.handlers.FilterHandler$FilterChainImpl.doFilter(FilterHandler.java:131)
13:36:10,889 ERROR [stderr] (default task-6)    at io.undertow.servlet//io.undertow.servlet.handlers.FilterHandler.handleRequest(FilterHandler.java:84)
13:36:10,890 ERROR [stderr] (default task-6)    at io.undertow.servlet//io.undertow.servlet.handlers.security.ServletSecurityRoleHandler.handleRequest(ServletSecurityRoleHandler.java:62)
13:36:10,891 ERROR [stderr] (default task-6)    at io.undertow.servlet//io.undertow.servlet.handlers.ServletChain$1.handleRequest(ServletChain.java:65)
13:36:10,892 ERROR [stderr] (default task-6)    at io.undertow.servlet//io.undertow.servlet.handlers.ServletDispatchingHandler.handleRequest(ServletDispatchingHandler.java:36)
13:36:10,893 ERROR [stderr] (default task-6)    at org.wildfly.extension.undertow//org.wildfly.extension.undertow.security.SecurityContextAssociationHandler.handleRequest(SecurityContextAssociationHandler.java:78)
13:36:10,894 ERROR [stderr] (default task-6)    at io.undertow.core//io.undertow.server.handlers.PredicateHandler.handleRequest(PredicateHandler.java:43)
13:36:10,896 ERROR [stderr] (default task-6)    at io.undertow.servlet//io.undertow.servlet.handlers.security.SSLInformationAssociationHandler.handleRequest(SSLInformationAssociationHandler.java:131)
13:36:10,897 ERROR [stderr] (default task-6)    at io.undertow.servlet//io.undertow.servlet.handlers.security.ServletAuthenticationCallHandler.handleRequest(ServletAuthenticationCallHandler.java:57)
13:36:10,897 ERROR [stderr] (default task-6)    at io.undertow.core//io.undertow.server.handlers.PredicateHandler.handleRequest(PredicateHandler.java:43)
13:36:10,898 ERROR [stderr] (default task-6)    at io.undertow.core//io.undertow.security.handlers.AbstractConfidentialityHandler.handleRequest(AbstractConfidentialityHandler.java:46)
13:36:10,899 ERROR [stderr] (default task-6)    at io.undertow.servlet//io.undertow.servlet.handlers.security.ServletConfidentialityConstraintHandler.handleRequest(ServletConfidentialityConstraintHandler.java:64)
13:36:10,900 ERROR [stderr] (default task-6)    at io.undertow.core//io.undertow.security.handlers.AuthenticationMechanismsHandler.handleRequest(AuthenticationMechanismsHandler.java:60)
13:36:10,901 ERROR [stderr] (default task-6)    at io.undertow.servlet//io.undertow.servlet.handlers.security.CachedAuthenticatedSessionHandler.handleRequest(CachedAuthenticatedSessionHandler.java:77)
13:36:10,902 ERROR [stderr] (default task-6)    at io.undertow.core//io.undertow.security.handlers.NotificationReceiverHandler.handleRequest(NotificationReceiverHandler.java:50)
13:36:10,903 ERROR [stderr] (default task-6)    at io.undertow.core//io.undertow.security.handlers.AbstractSecurityContextAssociationHandler.handleRequest(AbstractSecurityContextAssociationHandler.java:43)
13:36:10,905 ERROR [stderr] (default task-6)    at io.undertow.core//io.undertow.server.handlers.PredicateHandler.handleRequest(PredicateHandler.java:43)
13:36:10,906 ERROR [stderr] (default task-6)    at org.wildfly.extension.undertow//org.wildfly.extension.undertow.security.jacc.JACCContextIdHandler.handleRequest(JACCContextIdHandler.java:61)
13:36:10,907 ERROR [stderr] (default task-6)    at io.undertow.core//io.undertow.server.handlers.PredicateHandler.handleRequest(PredicateHandler.java:43)
13:36:10,908 ERROR [stderr] (default task-6)    at org.wildfly.extension.undertow//org.wildfly.extension.undertow.deployment.GlobalRequestControllerHandler.handleRequest(GlobalRequestControllerHandler.java:68)
13:36:10,909 ERROR [stderr] (default task-6)    at io.undertow.core//io.undertow.server.handlers.PredicateHandler.handleRequest(PredicateHandler.java:43)
13:36:10,910 ERROR [stderr] (default task-6)    at io.undertow.servlet//io.undertow.servlet.handlers.ServletInitialHandler.handleFirstRequest(ServletInitialHandler.java:292)
13:36:10,911 ERROR [stderr] (default task-6)    at io.undertow.servlet//io.undertow.servlet.handlers.ServletInitialHandler.access$100(ServletInitialHandler.java:81)
13:36:10,912 ERROR [stderr] (default task-6)    at io.undertow.servlet//io.undertow.servlet.handlers.ServletInitialHandler$2.call(ServletInitialHandler.java:138)
13:36:10,913 ERROR [stderr] (default task-6)    at io.undertow.servlet//io.undertow.servlet.handlers.ServletInitialHandler$2.call(ServletInitialHandler.java:135)
13:36:10,914 ERROR [stderr] (default task-6)    at io.undertow.servlet//io.undertow.servlet.core.ServletRequestContextThreadSetupAction$1.call(ServletRequestContextThreadSetupAction.java:48)
13:36:10,915 ERROR [stderr] (default task-6)    at io.undertow.servlet//io.undertow.servlet.core.ContextClassLoaderSetupAction$1.call(ContextClassLoaderSetupAction.java:43)
13:36:10,916 ERROR [stderr] (default task-6)    at org.wildfly.extension.undertow//org.wildfly.extension.undertow.security.SecurityContextThreadSetupAction.lambda$create$0(SecurityContextThreadSetupAction.java:105)
13:36:10,917 ERROR [stderr] (default task-6)    at org.wildfly.extension.undertow//org.wildfly.extension.undertow.deployment.UndertowDeploymentInfoService$UndertowThreadSetupAction.lambda$create$0(UndertowDeploymentInfoService.java:1501)
13:36:10,918 ERROR [stderr] (default task-6)    at org.wildfly.extension.undertow//org.wildfly.extension.undertow.deployment.UndertowDeploymentInfoService$UndertowThreadSetupAction.lambda$create$0(UndertowDeploymentInfoService.java:1501)
13:36:10,919 ERROR [stderr] (default task-6)    at org.wildfly.extension.undertow//org.wildfly.extension.undertow.deployment.UndertowDeploymentInfoService$UndertowThreadSetupAction.lambda$create$0(UndertowDeploymentInfoService.java:1501)
13:36:10,920 ERROR [stderr] (default task-6)    at org.wildfly.extension.undertow//org.wildfly.extension.undertow.deployment.UndertowDeploymentInfoService$UndertowThreadSetupAction.lambda$create$0(UndertowDeploymentInfoService.java:1501)
13:36:10,921 ERROR [stderr] (default task-6)    at org.wildfly.extension.undertow//org.wildfly.extension.undertow.deployment.UndertowDeploymentInfoService$UndertowThreadSetupAction.lambda$create$0(UndertowDeploymentInfoService.java:1501)
13:36:10,922 ERROR [stderr] (default task-6)    at io.undertow.servlet//io.undertow.servlet.handlers.ServletInitialHandler.dispatchRequest(ServletInitialHandler.java:272)
13:36:10,924 ERROR [stderr] (default task-6)    at io.undertow.servlet//io.undertow.servlet.handlers.ServletInitialHandler.access$000(ServletInitialHandler.java:81)
13:36:10,925 ERROR [stderr] (default task-6)    at io.undertow.servlet//io.undertow.servlet.handlers.ServletInitialHandler$1.handleRequest(ServletInitialHandler.java:104)
13:36:10,926 ERROR [stderr] (default task-6)    at io.undertow.core//io.undertow.server.Connectors.executeRootHandler(Connectors.java:330)
13:36:10,926 ERROR [stderr] (default task-6)    at io.undertow.core//io.undertow.server.HttpServerExchange$1.run(HttpServerExchange.java:812)
13:36:10,927 ERROR [stderr] (default task-6)    at java.base/java.util.concurrent.ThreadPoolExecutor.runWorker(ThreadPoolExecutor.java:1128)
13:36:10,928 ERROR [stderr] (default task-6)    at java.base/java.util.concurrent.ThreadPoolExecutor$Worker.run(ThreadPoolExecutor.java:628)
13:36:10,929 ERROR [stderr] (default task-6)    at java.base/java.lang.Thread.run(Thread.java:834)

Answer 1

I found the solution finally. The Problem was, that our JBoss Wildfly Server used Jackson Libraries as well and they caused an conflict. Probably because of the Version, which was something around 1.*

As soon as I excluded those old jackson libraries, @JsonAlias worked as expected:

<jboss-deployment-structure>
<deployment>
    <exclusions>
        <module name="com.fasterxml.jackson.core.jackson-core" />
        <module name="com.fasterxml.jackson.core.jackson-databind" />
        <module name="com.fasterxml.jackson.jaxrs.jackson-jaxrs-json-provider" />
        <module name="org.jboss.resteasy.resteasy-jackson2-provider" />
    </exclusions>
</deployment>

Answer 2

Try to use @JsonPropery instead of @JsonAlias

public class ExampleClass {

    @JsonProperty("test_1")  //Change 
    private String test1;

    @JsonProperty("test_2")  //Change
    private String test2;

    public String getTest1() {
        return test1;
    }

    public void setTest1(String test1) {
        this.test1 = test1;
    }

    public String getTest2() {
        return test2;
    }

    public void setTest2(String test2) {
        this.test2 = test2;
    }
}

See Javadoc