请教一个关于Class.forName的问题。

[baoma2000]

1 Class cls = Class.forName(jndiName);
2 BusinessBean SessionBean = (BusinessBean)cls.newInstance();
3 br = SessionBean.execute(pm);

BusinessBean的定义：
public interface BusinessBean {
public BusinessResult execute(int pm);
}
第1行能通过，第2行就不能了。请问该如何修改呢？

[takecare]

public class BusinessBean {
//constructor here

public abstract BusinessResult execute(int pm);
}

[ddbean]

缺少构造函数

[baoma2000]

还不是很明白？

[takecare]

你的接口定义了，但是为什么没有实现呢？是没有贴出来呢还是别的？

[Yssss1980]

你实例化的类是什么类啊

出什么错了，ClassNotFind?

[xiaohaiz]

把 String jndiName 内容告诉大家是什么？

[takecare]

是不是没有抓
java.lang.InstantiationException
exception

[takecare]

public Object newInstance()
throws InstantiationException,
IllegalAccessExceptionCreates a new instance of the class represented by this Class object. The class is instantiated as if by a new expression with an empty argument list. The class is initialized if it has not already been initialized.
If there is a security manager, this method first calls the security manager's checkMemberAccess method with this and Member.PUBLIC as its arguments. If the class is in a package, then this method also calls the security manager's checkPackageAccess method with the package name as its argument. Either of these calls could result in a SecurityException.


Returns:
a newly allocated instance of the class represented by this object.
Throws:
IllegalAccessException - if the class or its nullary constructor is not accessible.
InstantiationException - if this Class represents an abstract class, an interface, an array class, a primitive type, or void; or if the class has no nullary constructor; or if the instantiation fails for some other reason.
ExceptionInInitializerError - if the initialization provoked by this method fails.
SecurityException - if there is no permission to create a new instance.

[takecare]

我编译过你的程序的，没有问题，只要你抓了那些异常，所以我的1楼的回答是没有什么根据的（本来像是不是interface 不能 newInstance()）。

[takecare]

看来还是实践是检验真理的唯一标准。
哈哈

[baoma2000]

有点明白了，谢谢各位了。
public class BusinessBean {
//constructor here

public abstract BusinessResult execute(int pm);
}
这里也用BusinessBean名字没有问题社。