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TA貢獻1862條經驗 獲得超6個贊
版本2
ThrowableDeserializer類擴展,BeanDeserializer因此這兩個共享一些如何創建和反序列化POJO. Exception不是常規的POJO,應該以不同的方式處理。由于它沒有提供許多設置器,我們需要使用構造函數來使用消息和其他我們可以跳過的字段來創建它。要注冊構造函數,我們可以使用MixIn功能:
import com.fasterxml.jackson.annotation.JsonCreator;
import com.fasterxml.jackson.annotation.JsonIgnoreProperties;
import com.fasterxml.jackson.annotation.JsonProperty;
import com.fasterxml.jackson.databind.ObjectMapper;
import java.io.File;
public class JsonPathApp {
public static void main(String[] args) throws Exception {
File jsonFile = new File("./resource/test.json").getAbsoluteFile();
ObjectMapper mapper = new ObjectMapper();
mapper.addMixIn(Exception.class, ExceptionMixIn.class);
mapper.addMixIn(Throwable.class, ThrowableMixIn.class);
ExWrapper exW = mapper.readValue(jsonFile, ExWrapper.class);
exW.ex.printStackTrace();
}
}
@JsonIgnoreProperties("stackTrace")
abstract class ExceptionMixIn extends Exception {
@JsonCreator
public ExceptionMixIn(@JsonProperty("message") String message) {
super(message);
}
}
@JsonIgnoreProperties("stackTrace")
abstract class ThrowableMixIn extends Throwable {
@JsonCreator
public ThrowableMixIn(@JsonProperty("message") String message) {
super(message);
}
}
class ExWrapper {
public Exception ex;
@Override
public String toString() {
return "ExWrapper{" +
"ex=" + ex +
'}';
}
}
JSON上面的帶有原因的異常代碼打印:
java.lang.Exception: Opps
at sun.reflect.NativeConstructorAccessorImpl.newInstance0(Native Method)
at sun.reflect.NativeConstructorAccessorImpl.newInstance(NativeConstructorAccessorImpl.java:62)
at sun.reflect.DelegatingConstructorAccessorImpl.newInstance(DelegatingConstructorAccessorImpl.java:45)
at java.lang.reflect.Constructor.newInstance(Constructor.java:422)
at com.fasterxml.jackson.databind.introspect.AnnotatedConstructor.call(AnnotatedConstructor.java:124)
at com.fasterxml.jackson.databind.deser.std.StdValueInstantiator.createFromObjectWith(StdValueInstantiator.java:283)
at com.fasterxml.jackson.databind.deser.ValueInstantiator.createFromObjectWith(ValueInstantiator.java:229)
at com.fasterxml.jackson.databind.deser.impl.PropertyBasedCreator.build(PropertyBasedCreator.java:195)
at com.fasterxml.jackson.databind.deser.BeanDeserializer._deserializeUsingPropertyBased(BeanDeserializer.java:422)
at com.fasterxml.jackson.databind.deser.std.ThrowableDeserializer.deserializeFromObject(ThrowableDeserializer.java:65)
at com.fasterxml.jackson.databind.deser.BeanDeserializer.deserialize(BeanDeserializer.java:159)
at com.fasterxml.jackson.databind.deser.impl.FieldProperty.deserializeAndSet(FieldProperty.java:138)
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:4013)
at com.fasterxml.jackson.databind.ObjectMapper.readValue(ObjectMapper.java:2902)
Caused by: java.lang.Throwable: Root oops
at sun.reflect.NativeConstructorAccessorImpl.newInstance0(Native Method)
at sun.reflect.NativeConstructorAccessorImpl.newInstance(NativeConstructorAccessorImpl.java:62)
at sun.reflect.DelegatingConstructorAccessorImpl.newInstance(DelegatingConstructorAccessorImpl.java:45)
at java.lang.reflect.Constructor.newInstance(Constructor.java:422)
at com.fasterxml.jackson.databind.introspect.AnnotatedConstructor.call(AnnotatedConstructor.java:124)
at com.fasterxml.jackson.databind.deser.std.StdValueInstantiator.createFromObjectWith(StdValueInstantiator.java:283)
at com.fasterxml.jackson.databind.deser.ValueInstantiator.createFromObjectWith(ValueInstantiator.java:229)
at com.fasterxml.jackson.databind.deser.impl.PropertyBasedCreator.build(PropertyBasedCreator.java:195)
at com.fasterxml.jackson.databind.deser.BeanDeserializer._deserializeUsingPropertyBased(BeanDeserializer.java:422)
at com.fasterxml.jackson.databind.deser.std.ThrowableDeserializer.deserializeFromObject(ThrowableDeserializer.java:65)
at com.fasterxml.jackson.databind.deser.BeanDeserializer.deserialize(BeanDeserializer.java:159)
at com.fasterxml.jackson.databind.deser.SettableBeanProperty.deserialize(SettableBeanProperty.java:530)
at com.fasterxml.jackson.databind.deser.BeanDeserializer._deserializeWithErrorWrapping(BeanDeserializer.java:528)
at com.fasterxml.jackson.databind.deser.BeanDeserializer._deserializeUsingPropertyBased(BeanDeserializer.java:449)
... 8 more
如您所見,異常具有默認值stackTrace,并且會stackTrace跳過JSON有效負載。
版本1
我沒有深入挖掘它,但啟用allowSetters解決了這個問題:
@JsonIgnoreProperties(value = {"stackTrace"}, allowSetters = true)
public Exception ex;
進行此更改的代碼將打?。?/p>
{"ex":{"cause":null,"message":"Oops","localizedMessage":"Oops","suppressed":[]}}
ExWrapper{ex=java.lang.Exception: Oops}
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