OnJava8-Examples/onjava/Range.java at master · CSapprenticeWT/OnJava8-Examples · GitHub

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// onjava/Range.java

// We make no guarantees that this code is fit for any purpose.

// Visit http://OnJava8.com for more book information.

// Create arrays initialized with integer values.

package onjava;

public class Range {

// Produce sequence [start..end) incrementing by step

public static

int[] range(int start, int end, int step) {

if(step == 0)

throw new

IllegalArgumentException("Step cannot be zero");

int sz = Math.max(0, step >= 0 ?

(end + step - 1 - start) / step

: (end + step + 1 - start) / step);

int[] result = new int[sz];

for(int i = 0; i < sz; i++)

result[i] = start + (i * step);

return result;

} // Produce a sequence [start..end)

public static int[] range(int start, int end) {

return range(start, end, 1);

}

// Produce a sequence [0..n)

public static int[] range(int n) {

return range(0, n);

}