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Question

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

สารบัญ Show

What is a Character in Java?
What is a String in Java?
What is an Array in Java?
Let's Convert a String to a Character Array
1. Use toCharArray() Instance Method
2. Use charAt() Instance Method
More on Programming in Java

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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Happy Coding ❤️