我想建立一个取决于资源类类型的Mapper接口的通用工厂。Java通用工厂
下面是代码:
public interface Resource { }
public class IntegerResource implements Resource { }
public class IntegerMapper implements Mapper<IntegerResource> {
}
public static <R extends Resource> Mapper<R> buildMapper(Class<R> clazz){
if (IntegerResource.class.equals(clazz)){
return new IntegerMapper();//Compilation error: Type mismatch: cannot convert from IntegerMapper to Mapper<R>
}
return null;
}
public <R extends Resource> R getResource(Class<R> clazz){
Mapper<R> m = buildMapper(clazz);
return null;
}
问题是什么? – 2013-03-12 17:38:18
如何修复编译错误返回IntegerMapper(); //编译错误 – 2013-03-12 17:40:21