Question

我正在尝试使用JsonDeserialize类，但IDE显示编译错误。

GateAnnotation.scala

package com.scryAnalytics.NLPAnnotationController.DAO

import com.scryAnalytics.NLPGeneric.DAO.FeatureMapDeserializer
import org.codehaus.jackson.annotate.JsonProperty
import org.codehaus.jackson.map.annotate.JsonDeserialize
import gate.{FeatureMap, Node}
import gate.annotation.AnnotationImpl

/**
* Created by sahil on 22/11/16.
*/

class GateAnnotation(id: Integer, start: Node, end: Node, types: String, features: FeatureMap) extends
AnnotationImpl(id, start, end, types, features) {

private final  val serialVersionUID: Long = 1L
@JsonProperty
@JsonDeserialize(using = FeatureMapDeserializer.class)
}

FeatureMapDeserializer.scala

package com.scryAnalytics.NLPAnnotationController.DAO

import java.util.Map

import gate.{Factory, FeatureMap}
import org.apache.hadoop.yarn.webapp.hamlet.HamletSpec._Object
import org.codehaus.jackson.JsonParser
import org.codehaus.jackson.map.{DeserializationContext, JsonDeserializer}

class FeatureMapDeserializer extends JsonDeserializer[FeatureMap] {

override def deserialize(jsonParser: JsonParser, deserializationContext: DeserializationContext): FeatureMap = {
val features = jsonParser.readValueAs(classOf[Map[_Object, _Object]])
val featureMap = Factory.newFeatureMap()
featureMap.putAll(features)
 featureMap
} 
}

错误（编译）是 @JsonDeserialize（using = FeatureMapDeserializer.class）。悬停在线上后的错误是 FeatureMapDeserializer类型的表达式不符合预期类型Class [＆lt; JsonDeserializer [_]]

我无法弄清楚原因，所以我期待任何建议。

提前致谢。

Answer 1

您使用的是Java语法，而不是Scala语法。

@JsonProperty
@JsonDeserialize(using = classOf[FeatureMapDeserializer])
def foo = ???

Scson中的JsonDeserialize错误

1 个答案: