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Before we start, did you try solving the workbook yourself?

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If not, please click the link in the resources folder and follow the instructions for this workbook.

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Welcome to Workbook 7.4.

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Task one is to add a copy constructor inside the person class.

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So while our normal constructor gets called when we pass in four parameters while creating an object,

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the copy constructor is going to get called when we pass in another object.

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So we're going to set the name of the current object that's being created equal to the field value from

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our resource object.

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We're going to set the nationality of the current object being created equal to the nationality of the

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source object.

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We're going to set the date of birth of the current object being created equal to the date of birth

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from the source object from the object that was passed in.

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And we're going to set the seat number equal to source dot seat number.

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Okay.

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Your code contains a person object.

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The person's twin is also flying with Java Airlines.

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Use this code to test your copy constructor so we can copy this over.

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Here, we're creating a new object of the person class, and we're going to initialize this object as

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fields using another object.

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Because one object is our argument.

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It's going to call the constructor that expects to receive one object as a parameter.

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And once we create this object based on the old object, then we can update the newly created objects

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as name equal to another value, and then update their seat number as well.

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Let us go ahead and print the other person's fields as well.

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Before we start visualizing the runtime.

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So I'm going to put one breakpoint over here, one over here.

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And should be good.

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So here we're creating a new object of the person class passing in all of these values into the constructor.

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That means the constructor that expects to receive four parameters is going to get called.

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Here we set every single field inside of the current object that's being created equal to a parameter

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value.

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So first we're going to start with the name.

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We set this name equal to Rand Slim.

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We set this nationality equal to the parameter that was passed in Canadian.

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We set this date of birth equal to the date of birth that was passed in 11111.

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We set this seat number equal to the seat number that was passed in.

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All right.

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The person variable stores a reference to this object.

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And if I step inside here, set seat number gets called for this object.

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And what it's going to do is set the seat number for the current object equal to the seat number that

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was passed in.

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All right, beautiful.

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I'm just going to continue to the next breakpoint now.

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So at this point, it printed all of this object as fields.

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Here, once again, we're creating a new object of the person class.

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But because we're only passing in one argument, it's going to invoke the constructor that expects to

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receive one parameter, the copy constructor.

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And so here this points to the object that we just created, the one that has everything as null and

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zero.

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So if I step over here, we're setting every single field inside of the current object equal to a field

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value from the source object that we passed in.

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So here we're updating the name based on the source object.

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Here we're updating the nationality based on the source object.

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Here we update the date of birth, and here we update the seat number.

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The variable twin stores, a reference to the object that we just created based on the field values

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of another object.

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And now what we're going to do is call set name for the twin object.

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So I'm going to step inside here.

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We're updating the name of the current object called this method equal to the following value.

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Stepping inside a gun set seat number gets called for this object.

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Here we update the seat number from 10 to 3.

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Now if I step over.

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Here we print the field values of the first object, and here we print the field values of the second

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object, and we are done.