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Java

Ene Catalin
Ene Catalin
1,931 Points

I don't understand how the values from the returned array["chars" (readChars method)], are copied in the char[] message.

I thought that copying the values from one array to another, you must use a for loop(I know there may be more options), otherwise only the reference address is copied.

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1 Answer

Brendan Whiting
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Brendan Whiting
Front End Web Development Techdegree Graduate 84,738 Points

Arrays in Java have to be allocated in memory with a specific length when they get created. We can allocated an empty array with a certain size/length, and then fill it with values later. The readChars method takes an integer parameter. Then the first thing it does is allocate a new char array with that integer size, with nothing in the array yet.

Then it opens a for loop, iterating that same number of times - the int parameter that was passed in which is now the length of the chars array. I assume ITools.readChar() prompts the user for a character. So each time through the for loop, we get another character from the user, and we assign it to the position in the char array with the i index value. By the end of this function, we'll have assembled an array full of chars from the user, with a length according to the argument passed in, and it returns the array.