WEBVTT

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In previous demos i've used BlueJ to create objects

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to call methods of those objects

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now i'm going to show you the instructions in Java

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that perform the same actions.

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I need to open another window in BlueJ

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called the terminal window

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and i need to choose the option

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record method calls, this means as we 

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perform an action in BlueJ

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the equivalent Java instruction

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will be shown in the terminal window

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and I'm going to resize the main BlueJ window,

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so that the terminal window isn't hidden

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when I'm working in the main window.

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Let's create an object in exactly the same way as before

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I'll supply parameters for the constructor

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click Ok, and the object is created in the object bench

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and here's the equivalent Java instruction

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to create exactly that object

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let's call a method

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going to setPedalRpm to three hundred again as I did before

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and there's the Java instruction to call that method.

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Let's call the speed method

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the speed method returns a value

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and again we can see

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the instruction to call the speed method, and we can see

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the value that was returned by that method.

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Let's change the gear, calling the changeGear method

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and we will change up so a parameter of one

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and here's the instruction to do that

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and finally I'll call the speed method again just

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to see that the speed has changed

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we can see the return value

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in the method result dialogue box

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and we can see the instruction again to call

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the speed method and the return value.