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Let's sort of get a feature called auto boxing which is irrelevant to box produce prior to Delphi one

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had to manually create a box or two by invoking either its constructor or the value of mattered.

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We already know that.

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But in Josephite a feature called auto boxing was introduced and it's a feature of compiler as the name

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Autor boxing suggests the compiler can automatically block separate McGoo.

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That is if needed a compiler can automatically convert a parameter into the box perimeter.

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What this means is we can directly assign a perimeter to a box perimeter.

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That is where assigning a literal directly to an object reference like in the case of a string.

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Here the little quantified is assigned to an object reference and the compiler does Arto boxing that

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is it inserts the necessary code into the Java code as shown here.

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No just like other boxing.

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There is also Arto unboxing which allows a box primitive to be assigned to a primitive variable.

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He had a box but the model is assigned to.

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Variable g.

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And the compiler does auto unboxing by invoking the interview method.

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We call that we need to use our new method for unwrapping.

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So that's basically of boxing an auto unboxing videos we can not directly either put them into a data

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structure like idlest.

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Recall that this was not possible before.

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So Autobots implemented this.

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That is internally the compiler automatically converts perimeter into boxman box or do by doing something

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like this before Delphi.

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We had to do this manually.

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So what is the benefit of this.

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The code is less verbose now and it looks a lot cleaner.

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Also note that the title says metheglin location and that's because here are is a method in the class

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idlest and we are invoking it to add an element.

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Here's another example of a method invocation.

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Here we have the matter girl whose parameter is a box put him into an auto boxing variable to invoke

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it with it.

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Put him into this example demonstrates Arto unboxing here the method go has a perimeter parameter but

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do the auto unboxing variable to invoke it with the box but to C compiler is going to unwrap the boxes

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medu before making the invocation.

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You can on top of them.

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I did megacorporations directly on box primitives for example.

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Here we are creating a box perimeter and then we are incrementing it just like the VB increment primitive

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value.

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Similarly you can how Eric Maduka operations involving.

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But in order literal and a box primitive.

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Not that auto boxing does not work with Rs.

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For example this statement would be illegal.

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Let's actually look at the statement in court just to see the error message.

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Here is the exact same statement.

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So let's just go ahead and compiler.

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So I see you can see it gives a compilation error on your test incompatible types and they cannot be

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converted to integer.

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OK so this is entirely and this is in digerati under test and that it cannot be converted to degenerate

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.

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No the most likely reason for this could be that it would be very expensive to create a new array and

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then convert each element into a box primitive auto box and is an expensive operation as we will see

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in the next lesson.

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Now just imagine a method parameter that is an array of type in Biggert us OK and then some code is

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invoking the method with an array of primitives.

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So every call would require auto boxing of every element in the army and that would cause a lot of performance

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issues that support auto boxing.

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Our next move.

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Look at some potential performance issues due to auto boxing and auto unboxing