[New] added new formatting functions in StringHelper

- formatNanoDuration(long:nanos):String
- formatMillisecondsDuration(millis:long):String

pom.xml

@@ -1,6 +1,7 @@
 <project xmlns="http://maven.apache.org/POM/4.0.0" xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"
   xsi:schemaLocation="http://maven.apache.org/POM/4.0.0 http://maven.apache.org/maven-v4_0_0.xsd">
   <modelVersion>4.0.0</modelVersion>
+  
   <groupId>ch.eitchnet</groupId>
   <artifactId>ch.eitchnet.utils</artifactId>
   <packaging>jar</packaging>

src/main/java/ch/eitchnet/utils/helper/StringHelper.java

@@ -413,4 +413,40 @@ public class StringHelper {
 
 		return sb.toString();
 	}
+
+	/**
+	 * Formats the given number of milliseconds to a time like 0.000s/ms
+	 * 
+	 * @param millis
+	 *            the number of milliseconds
+	 * 
+	 * @return format the given number of milliseconds to a time like 0.000s/ms
+	 */
+	public static String formatMillisecondsDuration(final long millis) {
+		if (millis > 1000) {
+			return String.format("%.3fs", (((double) millis) / 1000)); //$NON-NLS-1$
+		}
+
+		return millis + "ms"; //$NON-NLS-1$
+	}
+
+	/**
+	 * Formats the given number of nanoseconds to a time like 0.000s/ms/us/ns
+	 * 
+	 * @param nanos
+	 *            the number of nanoseconds
+	 * 
+	 * @return format the given number of nanoseconds to a time like 0.000s/ms/us/ns
+	 */
+	public static String formatNanoDuration(final long nanos) {
+		if (nanos > 1000000000) {
+			return String.format("%.3fs", (((double) nanos) / 1000000000)); //$NON-NLS-1$
+		} else if (nanos > 1000000) {
+			return String.format("%.3fms", (((double) nanos) / 1000000)); //$NON-NLS-1$
+		} else if (nanos > 1000) {
+			return String.format("%.3fus", (((double) nanos) / 1000)); //$NON-NLS-1$
+		} else {
+			return nanos + "ns"; //$NON-NLS-1$
+		}
+	}
 }