java - 如何实例化一个类

Question

我的应用程序有问题，我无法实例化一个类

这是我的java.lang.ClassCastException

eclipse.emf.editeurgraphique.risque.features.StartEventFeature$CreateStartEventFeature cannot be cast to org.eclipse.graphiti.features.ICreateFeature 
at eclipse.emf.editeurgraphique.risque.features.StartEventFeature.getCreateFeature(StartEventFeature.java:43)

这是我的方法：

 public ICreateFeature getCreateFeature(IFeatureProvider fp) {
    return (ICreateFeature) new CreateStartEventFeature(fp);
}

我的界面：

public interface ICreateFeature extends ICreate, IFeature {
 }

和我的班级

 public CreateStartEventFeature(IFeatureProvider fp) {
        super(fp, "Start Event", "Indicates the start of a process or    choreography");
    }

Answer 1

这个问题有点令人困惑，因为它没有显示整个问题，但我假设 CreateStartEventFeature 实现了 ICreateFeature，因此请尝试省略显式转换：

public ICreateFeature getCreateFeature(IFeatureProvider fp) {
    return new CreateStartEventFeature(fp);
}

Answer 2

您的 CreateStartEventFeature 不会扩展您定义的任何类，因此通过调用超级构造函数

super(fp, "Start Event", "Indicates the start of a process or    choreography");

您尝试从 Object 类运​​行参数化构造函数。

Answer 3

CreateStartEventFeature 需要实现接口：

public class CreateStartEventFeature extends MyBaseClass implements ICreateFeature 
{...}