@Override
  public String toString() {
    final StringBuilder builder = new StringBuilder();
    for (final ZyLineContent content : m_content) {
      builder.append(content.toString());
      builder.append('\n');
    }
    return builder.toString();
  }
Adds another line add the end of the label content.

@param line The line to add.
java/zylib/src/main/java/com/google/security/zynamics/zylib/gui/zygraph/realizers/ZyLabelContent.java