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A value of null denotes the null proxy. The null proxy is a dedicated value that indicates that a proxy points "nowhere" (denotes no object).

Interface Inheritance in Java

Inheritance relationships among Slice interfaces are maintained in the generated Java classes. For example:

interface A { ... }
interface B { ... }
interface C extends A, B { ... }

The generated code for CPrx reflects the inheritance hierarchy:

public interface CPrx extends APrx, BPrx
{
    ...
}

Given a proxy for C, a client can invoke any operation defined for interface C, as well as any operation inherited from C's base interfaces.

The ObjectPrx Interface in Java

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