使用 xstream 在 Scala 中将 xml 转换为对象或映射时出错

Question

我正在尝试使用 xstream 将 xml 隐藏到对象:-

  def convert(xml: String) = {

      val xstream = new XStream(new DomDriver)
      val convertedMap:testing =  xstream.fromXML(xml).asInstanceOf[testing];
      convertedMap
  }
  val justtest:String = "<testing><note>5</note></testing>"
  convert(justtest)

测试class定义如下：-

class testing {

  private var note = None;

}

我收到以下错误：-

java.lang.InstantiationError: testing
    at sun.reflect.GeneratedSerializationConstructorAccessor28.newInstance(sum.sc)
    at java.lang.reflect.Constructor.newInstance(sum.sc:419)
    at com.thoughtworks.xstream.converters.reflection.Sun14ReflectionProvider.newInstance(sum.sc:71)
    at com.thoughtworks.xstream.converters.reflection.AbstractReflectionConverter.instantiateNewInstance(sum.sc:424)
    at com.thoughtworks.xstream.converters.reflection.AbstractReflectionConverter.unmarshal(sum.sc:229)
    at com.thoughtworks.xstream.core.TreeUnmarshaller.convert(sum.sc:68)
    at com.thoughtworks.xstream.core.AbstractReferenceUnmarshaller.convert(sum.sc:61)
    at com.thoughtworks.xstream.core.TreeUnmarshaller.convertAnother(sum.sc:62)
    at com.thoughtworks.xstream.core.TreeUnmarshaller.convertAnother(sum.sc:46)
    at com.thoughtworks.xstream.core.TreeUnmarshaller.start(sum.sc:130)
    at com.thoughtworks.xstream.core.AbstractTreeMarshallingStrategy.unmarshal(sum.sc:28)
    at com.thoughtworks.xstream.XStream.unmarshal(sum.sc:1054)
    at com.thoughtworks.xstream.XStream.unmarshal(sum.sc:1038)
    at com.thoughtworks.xstream.XStream.fromXML(sum.sc:909)
    at com.thoughtworks.xstream.XStream.fromXML(sum.sc:900)
    at #worksheet#.convert(sum.sc:26)
    at #worksheet#.#worksheet#(sum.sc:30)

请帮忙解决以上问题。

还有没有办法直接将 xml 转换成 scala 中的地图？

Answer 1

我没问题运行你的代码：

import com.thoughtworks.xstream.XStream
import com.thoughtworks.xstream.io.xml.DomDriver

object Main {
  def main(args: Array[String]): Unit = {
    val justtest:String = "<Testing><note>5</note></Testing>"
    convert(justtest)
  }

  def convert(xml: String) = {
    val xstream = new XStream(new DomDriver)
    val convertedMap: Testing =  xstream.fromXML(xml).asInstanceOf[Testing]
    convertedMap
  }
}

class Testing {
  private var note = None
}

也许你的testingclass不在默认包里，所以是打包问题？

无论如何，您希望 None 类型的变量如何存储您的数据？也许您应该将其设为 String 或 Int。我不熟悉 Xstream，但如果你想让库直接映射 xml 到 Option，我认为你需要编写一个自定义转换器。这也适用于转换 to/from 地图。

使用 xstream 在 Scala 中将 xml 转换为对象或映射时出错

Error while Convert xml to Object or Map in Scala using xstream

xml

scala

object

xstream