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A primitive data type specifies the size and type of variable values, and it has no additional methods.

There are eight primitive data types in Java:

Data Type Size Description`byte`1 byte Stores whole numbers from -128 to 127`short`2 bytes Stores whole numbers from -32,768 to 32,767`int`4 bytes Stores whole numbers from -2,147,483,648 to 2,147,483,647`long`8 bytes Stores whole numbers from -9,223,372,036,854,775,808 to 9,223,372,036,854,775,807`float`4 bytes Stores fractional numbers. Sufficient for storing 6 to 7 decimal digits`double`8 bytes Stores fractional numbers. Sufficient for storing 15 decimal digits`boolean`1 bit Stores true or false values`char`2 bytes Stores a single character/letter or ASCII values

In this article, we’ll look at how to convert a string to an array of characters in Java. I'll also briefly explain to you what strings, characters, and arrays are.

What is a Character in Java?

Characters are primitive datatypes. A character is a single character enclosed inside single quotation marks. It can be a letter, a digit, a punctuation mark, a space or something similar. For example: char firstVowel = 'a';

What is a String in Java?

Strings are objects (reference type). A string is made up of a string of characters. It's anything inside double quotation marks. For example: String vowels = "aeiou";

What is an Array in Java?

Arrays are fundamental data structures which can store fixed number of elements of the same data type in Java. For example, let's declare an array of characters: char[] vowelArray = {'a', 'e', 'i', 'o', 'u'};

Now, we have a basic understanding about what strings, characters, and arrays are.

Let's Convert a String to a Character Array

1. Use toCharArray() Instance Method

toCharArray() is an instance method of the String class. It returns a new character array based on the current string object.

Let's check out an example: // define a string String vowels = "aeiou"; // create an array of characters char[] vowelArray = vowels.toCharArray(); // print vowelArray System.out.println(Arrays.toString(vowelArray));

Output: [a, e, i, o, u]

When we convert a string to an array of characters, the length remains the same. Let's check the length of both String vowels = "aeiou";

0 and String vowels = "aeiou";

1 : System.out.println("Length of \'vowels\' is " + vowels.length()); System.out.println("Length of \'vowelArray\' is " + vowelArray.length);

Output: Length of 'vowels' is 5 Length of 'vowelArray' is 5

We can use various ways to print an array. I used the String vowels = "aeiou";

2 static method from the String vowels = "aeiou";

3 utility class.

You can read more about the toCharArray() instance method in the .

2. Use charAt() Instance Method

String vowels = "aeiou";

5 is an instance method of the String class. It returns a character at the specified index of the current string.

NOTE: a string is zero index based, similar to an array.

Let's see how we can convert a string to an array of characters using String vowels = "aeiou";

5 : // define a string String vowels = "aeiou"; // create an array of characters. Length is vowels' length char[] vowelArray = new char[vowels.length()]; // loop to iterate each characters in the 'vowels' string for (int i = 0; i < vowels.length(); i++) { // add each character to the character array vowelArray[i] = vowels.charAt(i); } // print the array System.out.println(Arrays.toString(vowelArray));

Output: [a, e, i, o, u]

You can read more about the String vowels = "aeiou";

5 instance method in the .

I just showed you another way of converting a string to a character array, but we can use the toCharArray() method to easily convert instead of creating loops and iterating them.

Please feel free to let me know if you have any suggestions or questions.

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More on Programming in Java

1. Object-Oriented Programming Principles in Java: OOP Concepts for Beginners
2. Java Array Methods – How to Print an Array in Java
3. Java String to Int – How to Convert a String to an Integer
4. Java Random Number Generator – How to Generate Integers With Math Random

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