# Wrapper

`WrapperProxetta` works differently than `ProxyProxetta`: instead of extending the target class, it creates new class that delegates call to target instance.

### WrapperProxetta overview

![](/files/-MUytg364gK0tS9ivmlb)

`WrapperProxetta` generates new class that delegates calls to target class instance. It is not enough to create a wrapper class and the instance - you must inject the target instead into it, too.

There are 3 ways how to build a wrapper.

#### Wrapper over class

Resulting object is custom type that implements all interfaces of the target. All target methods are wrapped.

#### Wrapper over class, casted to interface

Similar as above, except the resulting type implements one interface (provided by user). Still, all target methods are wrapped, even those that does not belong to the interface. They can be invoked using e.g. reflection.

#### Wrapper over interface

Resulting object has one interface, and only interface methods are wrapped.

### Example

Here is an example of how to create wrapper class and inject target instance into it.

```java
WrapperProxetta proxetta = Proxetta
    .wrapperProxetta()
    .withAspect(aspect);
WrapperProxettaFactory factory = proxetta
    .proxy()
    .setTarget(calc.getClass())
    .setTargetInterface(Calc.class);

Calc calc = factory.newInstance();
factory.injectTargetIntoWrapper(calc, calculatorObject);
```


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