Finding the max/min value in an array of primitives using Java

Nick Heiner picture Nick Heiner · Sep 27, 2009 · Viewed 626.2k times · Source

It's trivial to write a function to determine the min/max value in an array, such as:

/**
 * 
 * @param chars
 * @return the max value in the array of chars
 */
private static int maxValue(char[] chars) {
    int max = chars[0];
    for (int ktr = 0; ktr < chars.length; ktr++) {
        if (chars[ktr] > max) {
            max = chars[ktr];
        }
    }
    return max;
}

but isn't this already done somewhere?

Answer

Michael Rutherfurd picture Michael Rutherfurd · Sep 28, 2009

Using Commons Lang (to convert) + Collections (to min/max)

import java.util.Arrays;
import java.util.Collections;

import org.apache.commons.lang.ArrayUtils;

public class MinMaxValue {

    public static void main(String[] args) {
        char[] a = {'3', '5', '1', '4', '2'};

        List b = Arrays.asList(ArrayUtils.toObject(a));

        System.out.println(Collections.min(b));
        System.out.println(Collections.max(b));
   }
}

Note that Arrays.asList() wraps the underlying array, so it should not be too memory intensive and it should not perform a copy on the elements of the array.