ReplaceTime.java

import org.apache.commons.lang.StringUtils;

public class ReplaceTime 
{
    static final int LOOPS = 100000;
    
    static void timeReplace() {
      long start = System.nanoTime();
      for (int i = 0; i < LOOPS; i++) {
        "foo;bar;car".replace(";", "%3B");
      }
      System.out.println("String.replace took: " + (System.nanoTime() - start)/1000 + " µs");
    }
    
    static void timeStringUtilsReplace() {
      long start = System.nanoTime();
      for (int i = 0; i < LOOPS; i++) {
        StringUtils.replace("foo;bar;car", ";", "%3B");
      }
      System.out.println("StringUtils.replace took: " + (System.nanoTime() - start)/1000 + " µs");
    }
    
    public static void main( String[] args )
    {
      timeReplace();
      timeStringUtilsReplace();
      timeReplace();
      timeStringUtilsReplace();
      timeReplace();
      timeStringUtilsReplace();
    }
}

String.replace took: 222957 µs
StringUtils.replace took: 107535 µs
String.replace took: 70163 µs
StringUtils.replace took: 11121 µs
String.replace took: 70630 µs
StringUtils.replace took: 12234 µs