Iterate through string array in Java

Question

I have String array with some components, this array has 5 components and it vary some times. What I would like to do is to iterate through that array and get the first comp

Answer 1

Those algorithms are both incorrect because of the comparison:

for( int i = 0; i < elements.length - 1; i++)

or

for(int i = 0; i + 1 < elements.length; i++) {

It's true that the array elements range from 0 to length - 1, but the comparison in that case should be less than or equal to. Those should be:

for(int i = 0; i < elements.length; i++) {

or

for(int i = 0; i <= elements.length - 1; i++) {

or

for(int i = 0; i + 1 <= elements.length; i++) {

The array ["a", "b"] would iterate as:

i = 0 is < 2: elements[0] yields "a"

i = 1 is < 2: elements[1] yields "b"

then exit the loop because 2 is not < 2.

The incorrect examples both exit the loop prematurely and only execute with the first element in this simple case of two elements.

Answer 2

You can do an enhanced for loop (for java 5 and higher) for iteration on array's elements:

String[] elements = {"a", "a", "a", "a"};   
for (String s: elements) {           
    //Do your stuff here
    System.out.println(s); 
}

Answer 3

String[] elements = { "a", "a","a","a" };

for( int i=0; i<elements.length-1; i++)
{
    String s1 = elements[i];
    String s2 = elements[i+1];
}

Answer 4

String current = elements[i];
if (i != elements.length - 1) {
   String next = elements[i+1];
}

This makes sure you don't get an ArrayIndexOutOfBoundsException for the last element (there is no 'next' there). The other option is to iterate to i < elements.length - 1. It depends on your requirements.