How to print array in java

Previous
Next

In this post, we will see how to print array in java.

There are multiple ways to print an array. Let’s go through few ways to print array in java.

Using Arrays.toString()

You can use Arrays.toString() method to print array in java. This is simplest ways to print an array.
Arrays.toString() returns string object.This String contains array in string format.
Let us understand with the code

Output:

[1, 6, 7, 9, 4]

Using deepToString() method

Basically Arrays.toString() works fine for a 1-dimensional arrays,but it won’t work for multidimensional arrays.
Let’s say we have 2-dimensional array as shown
1 2 3
4 5 6
7 8 9
To convert multidimensional arrays to string, you can use Arrays.deepToString() method. This is how you can print 2D array in java.

Output:

[[1, 2, 3], [4, 5, 6], [7, 8, 9]]

Using Java 8 Stream API

In java 8, you can convert array to Stream and print array with Stream’s foreach() method.

Output:

================
Printing 1D String array
================
India
China
Japan
Bhutan
================
Printing 1D Integer array
================
1
2
3
4
5
================
Printing 2D String array
================
Java
Python
Go
Kotlon
================
Printing 2D String array
================
10
20
30
40
50
60
70
80

As you can see we have seen how to print String array and Integer array in java using Stream.

Using for loop

You can iterate the array using for loop and print elements of array in java.

Output:

1 6 7 9 4
3rd element of array is: 7

Using for-each loop

For each works same as for loop but with differs syntax.

Output:

1 6 7 9 4

Print array in reverse order in java

You can iterate the array using for loop in reverse order and print the element. This will print array in reverse order.

Output:

4 9 7 6 1

Print array with custom objects

In case, you have custom object in the array, then you should override toString() method in custom class, else it will give you unexpected results.
Let’s see with the help of example
Create a simple class named Color.java

Create main class named PrintArrayOfColors.java

Output:

[org.arpit.java2blog.Color@1d251891, org.arpit.java2blog.Color@48140564, org.arpit.java2blog.Color@58ceff1, org.arpit.java2blog.Color@7c30a502]

If you notice, we don’t have toString() method in Color class, that’s why it is calling Object’s toString() method and we are not able to see meaningful results.

We need to override toString() method in Color class and we will get informative output.

When you run PrintListOfColorsMain again, you will get below output:

[Color{name=’Red’, colorCode=’#FF0000′}, Color{name=’Blue’, colorCode=’0000FF’}, Color{name=’White’, colorCode=’#FFFFFF’}, Color{name=’Green’, colorCode=’#008000′}]

As you can see, we have much meaningful output now.

That’s all about how to print array in java.

Previous
Next

Add Comment