我的项目的第一部分是构建一个超图
这是一个快速绘制的UML图
顶点类
public abstract class Vertex <T>{
int vertexId ;
T vertexValue ;
public abstract T computeVertexValue();
}
Imagevertex Class
public class ImageVertex extends Vertex<Map<String, Instance>>{
public ImageVertex(int id ) {
this.vertexId=id;
}
@Override
public Map<String, Instance> computeVertexValue(){
return null;
}
}
AbstractVertexFactory
public abstract class AbstractVertexFactory {
public abstract Vertex createVertex(int id);
public Vertex produceVertex(int id) {
Vertex vertex = createVertex(id);
vertex.computeVertexValue();
return vertex;
}
}
ImageFactory类
public class ImageFactory extends AbstractVertexFactory {
@Override
public Vertex createVertex(int id) {
// TODO Auto-generated method stub
return new ImageVertex(id);
}
}
模拟器
public class ImageFactorySimulator {
/**
* @param args
*/
public static void main(String[] args) {
AbstractVertexFactory imFactory= new ImageFactory();
ImageVertex im = (ImageVertex) imFactory.createVertex(0);
}
}
在模拟器中使用强制转换 我怎么能避免它?
答案 0 :(得分:2)
您可以使用
public abstract class AbstractVertexFactory <T extends Vertex> {
public abstract T createVertex(int id);
}
并且
public class ImageFactory extends AbstractVertexFactory<ImageVertex> {
@Override
public ImageVertex createVertex(int id) {
// TODO Auto-generated method stub
return new ImageVertex(id);
}
}
答案 1 :(得分:1)
试
abstract class AbstractVertexFactory<T extends Vertex> {
public abstract Vertex createVertex(int id);
}
class ImageFactory extends AbstractVertexFactory<ImageVertex> {
@Override
public ImageVertex createVertex(int id) {
return new ImageVertex(id);
}
}
答案 2 :(得分:1)
另一个答案是:
public abstract class Vertex <T>{
int vertexId ;
T vertexValue ;
public abstract T computeVertexValue();
}
public class ImageVertex extends Vertex<Map<String, Object>>{
public ImageVertex(int id ) {
this.vertexId=id;
}
@Override
public Map<String, Object> computeVertexValue(){
return null;
}
}
public abstract class AbstractVertexFactory<T extends Vertex> {
public abstract T createVertex(int id);
public T produceVertex(int id) {
T vertex = createVertex(id);
vertex.computeVertexValue();
return vertex;
}
}
public class ImageFactory extends AbstractVertexFactory<ImageVertex> {
@Override
public ImageVertex createVertex(int id) {
// TODO Auto-generated method stub
return new ImageVertex(id);
}
}
public class ImageFactorySimulator {
/**
* @param args
*/
public void ttt(String[] args) {
ImageFactory imFactory= new ImageFactory();
ImageVertex im = imFactory.createVertex(0);
}
}
答案 3 :(得分:0)
您可以使用:
public class ImageFactory extends AbstractVertexFactory {
@Override
public Vertex createVertex(int id) {
// TODO Auto-generated method stub
return createImageVertex(id);
}
public ImageVertex createImageVertex(int id) {
// TODO Auto-generated method stub
return new ImageVertex(id);
}
}
和
public class ImageFactorySimulator {
/**
* @param args
*/
public static void main(String[] args) {
AbstractVertexFactory imFactory= new ImageFactory();
ImageVertex im = imFactory.createImageVertex(0);
}
}