public String toString(String indent, String namePrefix) {
            if (from == null) {
                return getCommentAndName(indent, namePrefix) + " was added with value " + formatValue(indent, to);
            } else if (to == null) {
                return getCommentAndName(indent, namePrefix) + " with value " + formatValue(indent, from) + " was removed";
            }
            return getCommentAndName(indent, namePrefix) + " has changed from " + formatValue(indent, from) + " to " + formatValue(indent, to);
        }
This class aggregates information about config changes that causes a restart to be required.

@author Magnar Nedland
config-lib/src/main/java/com/yahoo/config/ChangesRequiringRestart.java