spring-boot - com.fasterxml.jackson.databind.JsonMappingException：java.util.Optional 不能转换为 java.time.LocalDate

问题描述

技术栈：Spring Boot 1.5.8、Java 8、JUnit 4、jackson 2.13.0、jackson-datatype-jdk8 2.9.6

我正在为涉及 JSON 和 POJO 之间的序列化和反序列化的服务编写单元测试。当我尝试使用 com.fasterxml.jackson.databind.ObjectMapper 将 java 对象转换为 json 时，它给了我以下错误，

com.fasterxml.jackson.databind.JsonMappingException: java.util.Optional cannot be cast to java.time.LocalDate (through reference chain: com.ctm.common.request.application.ApplicationRequest["payload"]->com.ctm.healthapply.model.request.HealthApplicationRequest["applicants"]->com.ctm.healthapply.model.request.application.ApplicationGroup["governmentRebateAcknowledgement"]->com.ctm.healthapply.model.request.application.GovernmentRebate.GovernmentRebateAcknowledgement["declarationDate"])

全程跟踪，

    at com.fasterxml.jackson.databind.JsonMappingException.wrapWithPath(JsonMappingException.java:392)
at com.fasterxml.jackson.databind.JsonMappingException.wrapWithPath(JsonMappingException.java:351)
at com.fasterxml.jackson.databind.ser.std.StdSerializer.wrapAndThrow(StdSerializer.java:316)
at com.fasterxml.jackson.databind.ser.std.BeanSerializerBase.serializeFields(BeanSerializerBase.java:782)
at com.fasterxml.jackson.databind.ser.BeanSerializer.serialize(BeanSerializer.java:178)
at com.fasterxml.jackson.databind.ser.BeanPropertyWriter.serializeAsField(BeanPropertyWriter.java:728)
at com.fasterxml.jackson.databind.ser.std.BeanSerializerBase.serializeFields(BeanSerializerBase.java:774)
at com.fasterxml.jackson.databind.ser.BeanSerializer.serialize(BeanSerializer.java:178)
at com.fasterxml.jackson.databind.ser.std.ReferenceTypeSerializer.serialize(ReferenceTypeSerializer.java:386)
at com.fasterxml.jackson.databind.ser.BeanPropertyWriter.serializeAsField(BeanPropertyWriter.java:728)
at com.fasterxml.jackson.databind.ser.std.BeanSerializerBase.serializeFields(BeanSerializerBase.java:774)
at com.fasterxml.jackson.databind.ser.BeanSerializer.serialize(BeanSerializer.java:178)
at com.fasterxml.jackson.databind.ser.BeanPropertyWriter.serializeAsField(BeanPropertyWriter.java:728)
at com.fasterxml.jackson.databind.ser.std.BeanSerializerBase.serializeFields(BeanSerializerBase.java:774)
at com.fasterxml.jackson.databind.ser.BeanSerializer.serialize(BeanSerializer.java:178)
at com.fasterxml.jackson.databind.ser.DefaultSerializerProvider._serialize(DefaultSerializerProvider.java:480)
at com.fasterxml.jackson.databind.ser.DefaultSerializerProvider.serializeValue(DefaultSerializerProvider.java:319)
at com.fasterxml.jackson.databind.ObjectMapper._writeValueAndClose(ObjectMapper.java:4569)
at com.fasterxml.jackson.databind.ObjectMapper.writeValueAsString(ObjectMapper.java:3822)
at com.ctm.healthapply.service.RequestResponseTransformServiceImplTest.testAUFApplicationFamily(RequestResponseTransformServiceImplTest.java:69)
at sun.reflect.NativeMethodAccessorImpl.invoke0(Native Method)
at sun.reflect.NativeMethodAccessorImpl.invoke(NativeMethodAccessorImpl.java:62)
at sun.reflect.DelegatingMethodAccessorImpl.invoke(DelegatingMethodAccessorImpl.java:43)
at java.lang.reflect.Method.invoke(Method.java:498)
at org.junit.runners.model.FrameworkMethod$1.runReflectiveCall(FrameworkMethod.java:50)
at org.junit.internal.runners.model.ReflectiveCallable.run(ReflectiveCallable.java:12)
at org.junit.runners.model.FrameworkMethod.invokeExplosively(FrameworkMethod.java:47)
at org.junit.internal.runners.statements.InvokeMethod.evaluate(InvokeMethod.java:17)
at org.junit.internal.runners.statements.RunBefores.evaluate(RunBefores.java:26)
at org.junit.runners.ParentRunner.runLeaf(ParentRunner.java:325)
at org.junit.runners.BlockJUnit4ClassRunner.runChild(BlockJUnit4ClassRunner.java:78)
at org.junit.runners.BlockJUnit4ClassRunner.runChild(BlockJUnit4ClassRunner.java:57)
at org.junit.runners.ParentRunner$3.run(ParentRunner.java:290)
at org.junit.runners.ParentRunner$1.schedule(ParentRunner.java:71)
at org.junit.runners.ParentRunner.runChildren(ParentRunner.java:288)
at org.junit.runners.ParentRunner.access$000(ParentRunner.java:58)
at org.junit.runners.ParentRunner$2.evaluate(ParentRunner.java:268)
at org.junit.runners.ParentRunner.run(ParentRunner.java:363)
at org.junit.runner.JUnitCore.run(JUnitCore.java:137)
at com.intellij.junit4.JUnit4IdeaTestRunner.startRunnerWithArgs(JUnit4IdeaTestRunner.java:69)
at com.intellij.rt.junit.IdeaTestRunner$Repeater.startRunnerWithArgs(IdeaTestRunner.java:33)
at com.intellij.rt.junit.JUnitStarter.prepareStreamsAndStart(JUnitStarter.java:235)
at com.intellij.rt.junit.JUnitStarter.main(JUnitStarter.java:54)
Caused by: java.lang.ClassCastException: java.util.Optional cannot be cast to java.time.LocalDate
at com.fasterxml.jackson.datatype.jsr310.ser.LocalDateSerializer.serialize(LocalDateSerializer.java:36)
at com.fasterxml.jackson.databind.ser.BeanPropertyWriter.serializeAsField(BeanPropertyWriter.java:728)
at com.fasterxml.jackson.databind.ser.std.BeanSerializerBase.serializeFields(BeanSerializerBase.java:774)
... 39 more

从我的 pom.xml 中，

<properties>
   <jackson.version>2.13.0</jackson.version>
   <jackson-datatype-jdk8.version>2.9.6</jackson-datatype-jdk8.version>
</properties>

 <!-- JSON serialization -->
    <dependency>
        <groupId>com.fasterxml.jackson.core</groupId>
        <artifactId>jackson-databind</artifactId>
        <version>${jackson.version}</version>
        <exclusions>
            <exclusion>
                <groupId>com.fasterxml.jackson.core</groupId>
                <artifactId>jackson-core</artifactId>
            </exclusion>
            <exclusion>
                <groupId>com.fasterxml.jackson.core</groupId>
                <artifactId>jackson-annotations</artifactId>
            </exclusion>
        </exclusions>
    </dependency>
    <dependency>
        <groupId>com.fasterxml.jackson.core</groupId>
        <artifactId>jackson-core</artifactId>
        <version>${jackson.version}</version>
        <exclusions>
            <exclusion>
                <groupId>com.fasterxml.jackson.core</groupId>
                <artifactId>jackson-databind</artifactId>
            </exclusion>
            <exclusion>
                <groupId>com.fasterxml.jackson.core</groupId>
                <artifactId>jackson-annotations</artifactId>
            </exclusion>
        </exclusions>
    </dependency>
    <dependency>
        <groupId>com.fasterxml.jackson.core</groupId>
        <artifactId>jackson-annotations</artifactId>
        <version>${jackson.version}</version>
        <exclusions>
            <exclusion>
                <groupId>com.fasterxml.jackson.core</groupId>
                <artifactId>jackson-core</artifactId>
            </exclusion>
            <exclusion>
                <groupId>com.fasterxml.jackson.core</groupId>
                <artifactId>jackson-databind</artifactId>
            </exclusion>
        </exclusions>
    </dependency>
    <dependency>
        <groupId>com.fasterxml.jackson.datatype</groupId>
        <artifactId>jackson-datatype-jdk8</artifactId>
        <version>${jackson-datatype-jdk8.version}</version>
    </dependency>

这个领域和它的吸气剂有问题，

@JsonSerialize(
    using = LocalDateSerializer.class
)
private LocalDate declarationDate;

public Optional<LocalDate> getDeclarationDate() {
    return Optional.ofNullable(this.declarationDate);
}

尝试 writeValueAsString 时发生错误，

ObjectMapper mapper = new ObjectMapper();
mapper.registerModule(new Jdk8Module());

String requestAsJson = mapper.writeValueAsString(healthModelApplyRequest);

请帮助解决这个问题。

标签： spring-bootjava-8jacksonjunit4jackson-databind

spring-boot - com.fasterxml.jackson.databind.JsonMappingException：java.util.Optional 不能转换为 java.time.LocalDate

问题描述

解决方案

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