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com.fasterxml.jackson.databind.exc.InvalidDefinitionException: Cannot construct instance of `java.util.function.Supplier. Jackson反序列化的规则 没有无参构造报错问题 ；
报错如下：
com.fasterxml.jackson.databind.exc.InvalidDefinitionException: Cannot construct instance of `java.util.function.Supplier` (no Creators, like default construct, exist): abstract types either need to be mapped to concrete types, have custom deserializer, or contain additional type informationat [Source: (String)"{"userName":"xxx","companyCode":"xx","orgCode":"xx","farmOrg":null,"businessId":"10","flag":"5","userId":xx,"externalId":xx,"externalIdSupplier":{},"path":"/swine-production/productionEfficiencyAsync","userAgent":"Mozilla/5.0 (Windows NT 10.0; Win64; x64) AppleWebKit/537.36 (KHTML, like Gecko) Chrome/120.0.0.0 Safari/537.36 Edg/120.0.0.0","device":null,"appId":"100","lang":"zh","oneid":null,"virtualCode":null}"; line: 1, column: 171] (through reference chain: cloudpc.common.web.utils.RequestInfo["externalIdSupplier"])at com.fasterxml.jackson.databind.exc.InvalidDefinitionException.from(InvalidDefinitionException.java:67)at com.fasterxml.jackson.databind.DeserializationContext.reportBadDefinition(DeserializationContext.java:1592)at com.fasterxml.jackson.databind.DeserializationContext.handleMissingInstantiator(DeserializationContext.java:1058)at com.fasterxml.jackson.databind.deser.AbstractDeserializer.deserialize(AbstractDeserializer.java:265)at com.fasterxml.jackson.databind.deser.impl.MethodProperty.deserializeAndSet(MethodProperty.java:129)at com.fasterxml.jackson.databind.deser.BeanDeserializer.vanillaDeserialize(BeanDeserializer.java:288)at com.fasterxml.jackson.databind.deser.BeanDeserializer.deserialize(BeanDeserializer.java:151)at com.fasterxml.jackson.databind.ObjectMapper._readMapAndClose(ObjectMapper.java:4218)at com.fasterxml.jackson.databind.ObjectMapper.readValue(ObjectMapper.java:3214)at com.fasterxml.jackson.databind.ObjectMapper.readValue(ObjectMapper.java:3182)at cloudpc.export.service.impl.CrystalExportServiceImpl$1.lambda$run$0(CrystalExportServiceImpl.java:241)at cloudpc.mq.api.rabbitmq.RabbitMQService$2.onMessage(RabbitMQService.java:128)at org.springframework.amqp.rabbit.listener.AbstractMessageListenerContainer.doInvokeListener(AbstractMessageListenerContainer.java:1647)at org.springframework.amqp.rabbit.listener.AbstractMessageListenerContainer.actualInvokeListener(AbstractMessageListenerContainer.java:1521)at org.springframework.amqp.rabbit.listener.AbstractMessageListenerContainer.invokeListener(AbstractMessageListenerContainer.java:1498)at org.springframework.amqp.rabbit.listener.AbstractMessageListenerContainer.doExecuteListener(AbstractMessageListenerContainer.java:1489)at org.springframework.amqp.rabbit.listener.AbstractMessageListenerContainer.executeListener(AbstractMessageListenerContainer.java:1433)at org.springframework.amqp.rabbit.listener.SimpleMessageListenerContainer.doReceiveAndExecute(SimpleMessageListenerContainer.java:970)at org.springframework.amqp.rabbit.listener.SimpleMessageListenerContainer.receiveAndExecute(SimpleMessageListenerContainer.java:916)at org.springframework.amqp.rabbit.listener.SimpleMessageListenerContainer.access$1600(SimpleMessageListenerContainer.java:83)at org.springframework.amqp.rabbit.listener.SimpleMessageListenerContainer$AsyncMessageProcessingConsumer.mainLoop(SimpleMessageListenerContainer.java:1291)at org.springframework.amqp.rabbit.listener.SimpleMessageListenerContainer$AsyncMessageProcessingConsumer.run(SimpleMessageListenerContainer.java:1197)at java.base/java.lang.Thread.run(Thread.java:834)报错类中cloudpc.common.web.utils.RequestInfo[“externalIdSupplier”] 字段反序列化失败
解决方案 在externalIdSupplier 加上注解 @JsonIgnore
作用：在json序列化时将java bean中的一些属性忽略掉，序列化和反序列化都受影响。
使用方法：一般标记在属性或者方法上，返回的json数据即不包含该属性。
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