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Why won't this print the user-inputted array in reverse?

January 3Hits:2

In Java, arrays don't override toString(), so if you try to print one directly, you get weird output including the memory location:

int[] intArray = new int[] {1, 2, 3, 4, 5}; System.out.println(intArray);     // prints something like '[[email protected]' 

But usually we'd actually want something more like [1, 2, 3, 4, 5]. What's the simplest way of doing that? Here are some example inputs and outputs:

// array of primitives: int[] intArray = new int[] {1, 2, 3, 4, 5}; //output: [1, 2, 3, 4, 5]  // array of object references: String[] strArray = new String[] {"John", "Mary", "Bob"}; //output: [John, Mary, Bob] 


In Java 5 Arrays.toString(arr) or Arrays.deepToString(arr) for arrays within arrays. Note that Object[] version calls .toString() of each object in array. If my memory serves me correct, the output is even decorated in the exact way you're asking.

Edit: Don't forget to add import java.util.Arrays; like this:

package packageName;
import java.util.Arrays;


// simple array
String[] array = new String[] {"John", "Mary", "Bob"};
//output: [John, Mary, Bob]

// nested array
String[][] deepArray = new String[][] {{"John", "Mary"}, {"Alice", "Bob"}};
//output: [[Ljava.lang.String;@106d69c, [Ljava.lang.String;@52e922]
//output: [[John, Mary], [Alice, Bob]]

//double Array
double[] arrayGiven = { 7.0, 9.0, 5.0, 1.0, 3.0 };
// Output [7.0, 9.0, 5.0, 1.0, 3.0 ]

//int Array
int[] arrayInt = { 7, 9, 5, 1, 3 };
// Output [7, 9, 5, 1, 3 ]

Always check the standard libraries first. Try:


or if your array contains other arrays as elements:


This is nice to know, however, as for "always check the standard libraries first" I'd never have stumbled upon the trick of Arrays.toString( myarray )

--since I was concentrating on the type of myarray to see how to do this. I didn't want to have to iterate through the thing: I wanted an easy call to make it come out similar to what I see in the Eclipse debugger and myarray.toString() just wasn't doing it.

import java.util.Arrays;
System.out.println( Arrays.toString( myarray ) );

In JDK1.8 you can use aggregate operations and a lambda expression:

String[] strArray = new String[] {"John", "Mary", "Bob"};

Arrays.asList(strArray).stream().forEach(s -> System.out.println(s));

/* output:

If you're using Java 1.4, you can instead do:


(This works in 1.5+ too, of course.)

Arrays.deepToString(arr) only prints on one line.

int[][] table = new int[2][2];

To actually get a table to print as a two dimensional table, I had to do this:

System.out.println(Arrays.deepToString(table).replaceAll("],", "]," + System.getProperty("line.separator")));

It seems like the Arrays.deepToString(arr) method should take a separator string, but unfortunately it doesn't.

for(int n: someArray) {
    System.out.println(n+" ");

Using regular for loop is the simplest way of printing array in my opinion. Here you have a sample code based on your intArray

for (int i = 0; i < intArray.length; i++) {
   System.out.print(intArray[i] + ", ");

It gives output as yours 1, 2, 3, 4, 5

Prior to Java 8 we could have used Arrays.toString(array) to print one dimensional array and Arrays.deepToString(array) for multi-dimensional arrays. We have got the option of Stream and lambda in Java 8 which can also be used for the printing the array.

Printing One dimensional Array:

public static void main(String[] args) {
    int[] intArray = new int[] {1, 2, 3, 4, 5};
    String[] strArray = new String[] {"John", "Mary", "Bob"};

    //Prior to Java 8

    // In Java 8 we have lambda expressions

The output is:

[1, 2, 3, 4, 5]
[John, Mary, Bob]

Printing Multi-dimensional Array Just in case we want to print multi-dimensional array we can use Arrays.deepToString(array) as:

public static void main(String[] args) {
    int[][] int2DArray = new int[][] { {11, 12}, { 21, 22}, {31, 32, 33} };
    String[][] str2DArray = new String[][]{ {"John", "Bravo"} , {"Mary", "Lee"}, {"Bob", "Johnson"} };

    //Prior to Java 8

    // In Java 8 we have lambda expressions
    Arrays.stream(int2DArray).flatMapToInt(x -> Arrays.stream(x)).forEach(System.out::println);
    Arrays.stream(str2DArray).flatMap(x -> Arrays.stream(x)).forEach(System.out::println);

Now the point to observe is that the method Arrays.stream(T[]), which in case of int[] returns us Stream<int[]> and then method flatMapToInt() maps each element of stream with the contents of a mapped stream produced by applying the provided mapping function to each element.

The output is:

[[11, 12], [21, 22], [31, 32, 33]]
[[John, Bravo], [Mary, Lee], [Bob, Johnson]]

Starting with Java 8, one could also take advantage of the join() method provided by the String class to print out array elements, without the brackets, and separated by a delimiter of choice (which is the space character for the example shown below):

String[] greeting = {"Hey", "there", "amigo!"};
String delimiter = " ";
String.join(delimiter, greeting)

The output will be "Hey there amigo!".

A simplified shortcut I've tried is this:

    int x[] = {1,2,3};
    String printableText = Arrays.toString(x).replaceAll("[\\[\\]]", "").replaceAll(", ", "\n");

It will print


No loops required in this approach and it is best for small arrays only

There's one additional way if your array is of type char[]:

char A[] = {'a', 'b', 'c'}; 

System.out.println(A); // no other arguments



public class printer {

    public static void main(String[] args) {
        String a[] = new String[4];
        Scanner sc = new Scanner(System.in);
        System.out.println("enter the data");
        for (int i = 0; i < 4; i++) {
            a[i] = sc.nextLine();
        System.out.println("the entered data is");
        for (String i : a) {

Using org.apache.commons.lang3.StringUtils.join(*) methods can be an option
For example:

String[] strArray = new String[] { "John", "Mary", "Bob" };
String arrayAsCSV = StringUtils.join(strArray, " , ");
System.out.printf("[%s]", arrayAsCSV);
//output: [John , Mary , Bob]

I used the following dependency


To add to all the answers, printing the object as a JSON string is also an option.

Using Jackson:

ObjectWriter ow = new ObjectMapper().writer().withDefaultPrettyPrinter();

Using Gson:

Gson gson = new Gson();

The simplest way to print an array is to use a for-loop:

// initialize array
for(int i=0;i<10;i++)
    System.out.print(array[i] + " ");

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