Converting a String array into an int Array in java

Question

I am new to java programming. My question is this I have a String array but when I am trying to convert it to an int array I keep getting

java.lang.NumberFormatException 

My code is

private void processLine(String[] strings) {     Integer[] intarray=new Integer[strings.length];     int i=0;     for(String str:strings){         intarray[i]=Integer.parseInt(str);//Exception in this line         i++;     } } 

Any help would be great thanks!!!

Answer 1

Suppose, for example, that we have a arrays of strings:

String[] strings = {"1", "2", "3"}; 

With Lambda Expressions^{[1] [2]} (since Java 8), you can do the next ▼:

int[] array = Arrays.asList(strings).stream().mapToInt(Integer::parseInt).toArray(); 

▼ This is another way:

int[] array = Arrays.stream(strings).mapToInt(Integer::parseInt).toArray(); 

_{—————————
Notes
  1. Lambda Expressions in The Java Tutorials.
  2. Java SE 8: Lambda Quick Start}

Answer 2

To get rid of additional whitespace, you could change the code like this:

intarray[i]=Integer.parseInt(str.trim()); // No more Exception in this line