How can I make this more elegant and applicable to any String? - string

Question

public class JavaIntern{
public static void main(String []args){
String str = "JavaIntern"; //hardcoded, but not the problem
char[] s = str.toCharArray();
String result = new String (s,0,1); //this is where the dilemma begins
System.out.println(result);
String result1 = new String (s,0,2);
System.out.println(result1);
String result2 = new String (s,0,3);
System.out.println(result2);
String result3 = new String (s,0,4);
System.out.println(result3);
String result4 = new String (s,0,5);
System.out.println(result4);
String result5 = new String (s,0,6);
System.out.println(result5);
String result6 = new String (s,0,7);
System.out.println(result6);
String result7 = new String (s,0,8);
System.out.println(result7);
String result8 = new String (s,0,9);
System.out.println(result8);
String result9 = new String (s,0,10);
System.out.println(result9); //and this is where it ends... how can I get rid of this?
}
}
//but still get this:
J
Ja
Jav
Java
JavaI
JavaIn
JavaInt
JavaInte
JavaInter
JavaIntern

Answer 1

I guess you want to improve the code and also don't depend on the length of the string.
What about something like this?
public class JavaIntern{
public static void main(String []args){
String str = "JavaIntern"; //hardcoded, but not the problem
String substring = "";
for (char ch: str.toCharArray()) {
substring += ch;
System.out.println(substring);
}
}
}
This will also print:
J
Ja
Jav
Java
JavaI
JavaIn
JavaInt
JavaInte
JavaInter
JavaIntern
The loop gets one character of the string at a time and concatenates it to the substring before printing it.

Answer 2

Im assuming you want to be able to print out one letter more each time.
To do this we use a for loop, and this way it is fairly simple.
public class MainClass {
public static void main(String[] args) {
String str = "JavaIntern";
for (int i = 1; i <= str.length(); i++) {
System.out.println(str.substring(0, i));
}
}
}
We set i to 0 in the loop, keep iterating while i less than or equal to the length of the string, and each time we iterate, add one to i.
We use the substring method to split the string from the first letter, to i.