How to create string array in java

How to create a String or int Array in Java? Example Tutorial

There are several ways to create an array in Java, for example, you can declare the array without initializing it, or you can create and initialize the array in the same line. If you want to make an array with values, then you need to first decide which type of array you want to create? e.g., do you want a String array, which can contain String objects like «abc,» «def,» or do you want to create an int array that contains int values like 10, 20, etc. In Java, you can create an array of any type, including primitives like byte , int , long, and objects like String , Integer , and other user-defined objects. Let’s some code to make a new array in Java.

1. Creating String array in Java

There are three main ways to create a String array in Java, e.g. here is a String array with values :

String[] platforms = "Nintendo", "Playstation", "Xbox">;

and here is a String array without values :

String[] games = new String[5];

This array can hold 5 String objects because its length is 5. It’s mandatory to define the length of a variety while making, and you cannot change the length once created.

You can also do something like this :

String[] actors = new String[5]"Hero", "Heroine", "Friend", "Villain", "Dragon">;

All there are correct ways to make an array in Java. Though, if you are not familiar with an essential data structure like an array and linked list, then I suggest you first go through these best data structure and algorithms online courses. It’s a very important topic for any programmer be it a core Java developer or Java web developer and you just can not afford to ignore this.

How to create an Int array in Java?

You can use the same syntax as shown above to create an int array, all you need to do is replace String with int values as shown below :

making an int array with values

length of this array is 5, hence it can only hold 5 int values. If you don’t assign values then by default they hold the default value of their type like int array will have zero in every index, and the String array will have null. You can further see these best Java online courses learn more about different types of the array in Java.

How to access array elements in Java?

You can access array elements using index, e.g. primes[0] will return the first element from an array that is referenced by the prime variable. Remember, the array index starts with zero. If you want to iterate over an array, i.e. wants to go access every element then you can use a loop, e.g. for, while or a do-while loop.

You can also use advanced for loop in Java, which allows you to iterate over array without index as shown below :

for(String str : platforms) System.out.println(str); // Nintendo, Playstation, Xbox >

The minimum index in the array is zero, and the maximum index is length — 1.

That’s all about how to make an array in Java. You have also learned how to initialize the array at the time they are created and how to access them with and without index using advanced for a loop. Though, there are many ways to create an array in Java and even more ways to loop over them. For example, you can also use while , do-while, and classic for loop to iterate over an array in Java.

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Java String Arrays: How to Create and Work with Them in Java

Learn how to create and work with string arrays in Java with this comprehensive guide. Discover how to declare, initialize, and convert string arrays in Java.

• What is a string array in Java?
• Declaration of a string array in Java
• Java Tutorial
• Initialization of a string array in Java
• Conversion of a string to a string array in Java
• Conversion of a string array to a string in Java
• Other helpful code examples for creating a string array in Java
• Conclusion
• How do you create a string array in Java?
• How do you make a string array?
• What is a string [] in Java?
• How do you initialize string array?

Java is one of the most popular programming languages in the world. It is widely used for building web applications, mobile apps, and desktop applications. One important feature of Java is the ability to use arrays, including string arrays. In this blog post, we will explore how to create a string array in java.

What is a string array in Java?

A string array is an array of fixed number of string values. In Java, a string is an immutable object. Java arrays can store primitive data types as well as objects. A string array is created to store multiple strings of fixed length.

Declaration of a string array in Java

There are two ways to declare a string array in Java: declaration without size and declaration with size. To define a string array of specific size in java, declare a string array and assign a new string array object to it with the size specified in the square brackets. Java arrays have a fixed size and cannot be resized during runtime.

Declaration without size

Declaration with size

String[] stringArray = new String[10]; 

Java Tutorial

Get more lessons like this at http://www.MathTutorDVD.comLearn how to program in java with Duration: 12:16

Initialization of a string array in Java

We can initialize a string array in Java by assigning a set of values to it using an array initializer or by assigning values to each element of the string array. Java arrays can be initialized after the declaration.

Initialization using an array initializer

Initialization by assigning values to each element of the string array

String[] stringArray = new String[5]; stringArray[0] = "apple"; stringArray[1] = "banana"; stringArray[2] = "cherry"; stringArray[3] = "date"; stringArray[4] = "elderberry"; 

Conversion of a string to a string array in Java

To convert a string to a string array in Java, we can use the split() method or the StringTokenizer class. The split() method splits a string into an array of substrings based on a delimiter. The StringTokenizer class splits a string into tokens based on a delimiter.

Conversion using split() method

String fruits = "apple,banana,cherry,date,elderberry"; String[] stringArray = fruits.split(","); 

Conversion using StringTokenizer class

String fruits = "apple,banana,cherry,date,elderberry"; StringTokenizer st = new StringTokenizer(fruits, ","); String[] stringArray = new String[st.countTokens()]; int i = 0; while (st.hasMoreTokens())

Conversion of a string array to a string in Java

To convert a string array to a string in Java, we can use the Arrays.toString() method. The Arrays.toString() method returns a string representation of the contents of the array. Java has built-in arrays and ArrayLists.

Conversion using Arrays.toString() method

String[] stringArray = ; String string = Arrays.toString(stringArray); 

Other helpful code examples for creating a string array in Java

In java, java new string array code example

String[] myStringArray = new String[3]; String[] myStringArray = ; String[] myStringArray = new String[];

In java, array of string java code example

//store input string in an array with an length unknown Scanner scanner = new Scanner(System.in); String[] string = scanner.nextLine().split(" ");

Conclusion

Java arrays are a powerful feature in Java programming, including string arrays. We’ve explored how to create a string array in Java, including declaration, initialization, and conversion. Java arrays have a fixed size and cannot be resized during runtime, so it’s important to plan accordingly. With this knowledge, you can now create and work with string arrays in java with confidence.

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How to declare a String array in java

In this declaration, a String array is declared as any normal variable without size. Before using this array, you need to instantiate it otherwise you might get variable might not have initialized error.

Declaring a String array with size

In this declaration, a String array is declared and instantiated at the same time. You can directly use this array, but you will see that myStrArr contains null values as it is not initialized yet.

Let’s see both types with the help of example:

How to declare and initialize String array in java

There are multiple ways to declare and initialize array in java.

Using new operator

We can declare and initialize array in java using new operator. We don’t have to provide size in this case.

You can also use variable name before [] .

Without Using new operator

We can also declare and initialize array in java without using new operator.

Splitting declaration and initialization of String array

We can also declare a String array and can initialize it later.

Using Arrays.fill() to initialize String array

We can also declare a String array and can initialize it later.

Using Java 8’s setAll() method to initialize String array

We can also use Java 8’s setAll() method and pass a generator to initialize String array in java.

How to declare and initialize an empty String array

There are two ways to create empty String array in java.

That’s all about how to declare a String array in java.

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