@Override
    public String toString() {
      return key + "=" + value;
    }
Returns a String representation of this map entry. This implementation returns the string
representation of this entry's key followed by the equals character ("<tt>=</tt>") followed
by the string representation of this entry's value.

@return a String representation of this map entry
geode-core/src/main/java/org/apache/geode/internal/util/concurrent/CustomEntryConcurrentHashMap.java