protected static boolean isSet(final Properties properties, final String propertyName) {
    return isNotBlank(properties.getProperty(propertyName));
  }
Determines whether the specified property with name is set to a value in the referenced
Properties. The property is considered "set" if the String value of the property is not
non-null, non-empty and non-blank. Therefore, the Properties may "have" a property with name,
but having no value as determined by this method.

@param properties the Properties used in determining whether the given property is set.
@param propertyName a String indicating the name of the property to check if set.
@return a boolean indicating whether the specified property with name has been given a value in
        the referenced Properties.
@see java.util.Properties
geode-core/src/main/java/org/apache/geode/distributed/AbstractLauncher.java