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It's time to learn how to a bitter race.

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So far, we use the for loop to run through the length of an array and now you know how to create arrays

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as well as how to access their values.

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The last step is to learn how to update them.

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So inside your Section six folder, create a new file named updating, Erase Java and inside the class,

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make sure there's a main method.

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Just like we can access array values from their index, we can update them all the same.

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So you have an array of three elements, if you want to change an element, just to refer to its index

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and then change the value.

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It's that simple.

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And so I prepared a fine example for us to learn about how to update race, you decided to pursue your

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lifelong dream, opened up a cafe, the Java Cafe, your menu starts off pretty simple.

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It offers three beverages, the espresso, iced coffee and macchiato.

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So inside the class, we're going to store the menu in one array string menu.

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Is going to equal an array of three string values.

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Espresso.

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Iced coffee and macchiato.

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Now, I don't know about you, but I'm a bit tired of using loops to print theory.

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Java has a function called to string.

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It takes your array as an argument and it returns a string that we can print.

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So first to write the word erase, wait a bit and click on the first option and what that's going to

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do is auto import the utility class.

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And so from the erased utility class, we can use the two string method.

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The two string method is going to take your array as an argument and return a string copy, we can store

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the string copy in a string variable.

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And this is really convenient because we can now print the contents of menu as one long string.

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Or on the code and nice to string returns a string copy of the array, which you can easily print.

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Now, instead of storing the return value, then printing it, I'd rather just print the return value

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in one line.

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And your coffee is all set up and people are going nuts, but nobody's buying the macchiato, so you

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decide to sell lattes instead.

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So we're going to do is we're going to update the value at index two and set it equal to latte.

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All right, Perfect's.

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Now, let's say you want to add more items to the menu, is it possible to change the array length?

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And the answer is a big fat no, you cannot change the length of an array.

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And that's really unfortunate because your Java cafe is becoming really popular and you need to expand

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your menu to accommodate new customers.

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There is a lot of demand for house blend and dark roast, but the problem is once you create an array,

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you cannot resize it.

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The current array only has a room for three items.

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So what I can do is create a new array that can store five string values.

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So inside the code, I'm going to create a new array that can hold five menu items, string menu.

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Is equal to new string that can hold five elements.

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The new area has five elements with indexes of zero to four, and by default, the values are null.

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Now we're going to create a loop that runs through every item in the old menu, so 4:00 a.m. is equal

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to zero.

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Remember, indexing an array always starts at zero.

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Just at the last index in the array is always one less than the array's length.

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And during each run, we're going to print the index I.

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As well as the value that we're indexing in the menu.

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All right, we're off to a good start.

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It runs through the length of the older ray and it prints every element.

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Now we need to copy each element from the old array into the new array.

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So I'm going to delete this code.

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And I'm going to set every element a new menu.

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Equal to the element in menu with the same index.

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And so from a visual standpoint, this loop runs three times in copies, every value from menu to the

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same index as new menu.

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To prove this, I'm going to print the contents of new menu as a string.

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And as you can see, the first three volumes are copies from the old array, because there was only

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three values, the copy from the old array.

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But we still have to add house blend and our coast our menu.

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So what we'll do is we'll update the element in the next three set that equal to house blend.

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And we'll update the elemental index for and set that equal to dark roast.

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Rewriting, running the code.

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And the Java Cafe is back in business, we successfully updated the menu and we're ready to accommodate

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more customers.

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From a visual standpoint, you updated the elements and indexes three and four.

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Now, your menu is complete and your customers are happy.

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In this lesson, you learn how to a bitter race.

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You opened up your first cafe, the menu only had three items, your cafe became very popular, so you

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decided to add house blend and darkness to your menu.

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The problem was you cannot resize an array once you created.

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You copied the three elements from menu and to new menu.

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And then you manually updated indexes three and four with houseplant and Dark Roast.