I want to initialize a string as follows:
public int function ( int count ) {
String s_new = "88888... 'count' number of 8's " <-- How to do this
//Other code
}
Currently I'm not sure how to do this, so I've declared an int array ( int[] s_new ) instead and Im using for loops to initialize this int array.
EDIT: I meant that I need to initialize a string containing only 8's ... the number of times the digit 8 occurs is 'count' times.
You can use Guava's Strings.repeat() method:
String str = Strings.repeat("8", count);
In these cases, it is recommended to use a StringBuilder:
StringBuilder sb = new StringBuilder();
String s = "";
int count = 8;
for (int i = 0; i < count; i++) {
sb.append('8');
}
s = sb.toString();
System.out.println(s);
Output:
88888888
+ operations are actually converted to StringBuilder.append's so I doubt it, but when dealing with 8 characters output you need to be sure to optimize everything
+ is internally implemented via StringBuilder but the compiler will do that in a loop here. new StringBuilder(s).append('8').toString() each time. You have move the builder out of the loop manually
Try:
String s_new = "";
for (int i = 0; i < count; i++) {
s_new += "8";
}
return s_new;
Now, this is a naive solution. A better solution (as is posted in other answers here) will use a StringBuffer or StringBuilder to accomplish this in a more efficient manner.
Also, further reading on the difference between those two options: Difference between StringBuilder and StringBuffer
You can build strings using the StringBuilder class.
StringBuilder sb = new StringBuilder();
for (int i = 0; i < count; i++)
sb.append('8')
String s_new = sb.toString();
s_new would then have as much 8 as you have count.
Solution on pure Java using arrays:
public String repeat(char ch, int count) {
char[] chars = new char[count];
Arrays.fill(chars, ch);
return new String(chars);
}
88888...part of the string supposed to represent the value ofcount? ie the user passes in 5, you put 5 eights there?