@Override
  public String toString() {
    StringBuilder s = new StringBuilder();
    s.append('{');
    s.append(HConstants.NAME);
    s.append(" => '");
    s.append(name);
    s.append("'");
    for (Map.Entry<String, String> e : configuration.entrySet()) {
      String key = e.getKey();
      String value = e.getValue();
      if (key == null) {
        continue;
      }
      s.append(", ");
      s.append(key);
      s.append(" => '");
      s.append(value);
      s.append("'");
    }
    s.append('}');
    return s.toString();
  }
Remove a config setting represented by the key from the {@link #configuration} map
hbase-common/src/main/java/org/apache/hadoop/hbase/NamespaceDescriptor.java