scala - 如何从Java “get”一个Scala案例对象？

Question

我在Scala中创建了案例对象的层次结构，如下所示:

package my.awesome.package

sealed abstract class PresetShapeType(val displayName: String)

case object AccelerationSensor extends PresetShapeType("Acceleration Sensor")
case object DisplacementSensor extends PresetShapeType("Displacement Sensor")
case object ForceSensor        extends PresetShapeType("Force Sensor")
case object PressureSensor     extends PresetShapeType("Pressure Sensor")
case object StrainSensor       extends PresetShapeType("Strain Sensor")

我也有一段Java代码，我想在其中访问PressureSensor，但是以下代码不起作用:

package my.awesome.package.subpackage;

import my.awesome.package.PressureSensor;

// Do some stuff, then...

DVShape newshape = DVShapeFactory.createPresetShape(PressureSensor, new Point3f(0,0,0));

那么，如何从Java引用PressureSensor大小写对象？我反编译了PressureSensor和PressureSensor$类的字节码，结果如下:

Compiled from "DVShapeFactory.scala"
public final class org.nees.rpi.vis.PressureSensor extends java.lang.Object{
    public static final java.lang.Object productElement(int);
    public static final int productArity();
    public static final java.lang.String productPrefix();
    public static final int $tag();
    public static final java.lang.String displayName();
}

Compiled from "DVShapeFactory.scala"
public final class org.nees.rpi.vis.PressureSensor$ extends org.nees.rpi.vis.PresetShapeType implements scala.ScalaObject,scala.Product,java.io.Serializable{
    public static final org.nees.rpi.vis.PressureSensor$ MODULE$;
    public static {};
    public org.nees.rpi.vis.PressureSensor$();
    public java.lang.Object readResolve();
    public java.lang.Object productElement(int);
    public int productArity();
    public java.lang.String productPrefix();
    public final java.lang.String toString();
    public int $tag();
}

但这并没有产生任何深刻的见解。

Answer 1

从Java说:

my.awesome.package.PressureSensor$.MODULE$