public void appendToBuffer(StringBuilder buffer) {
      if (DEBUG) {
        buffer.append("stack.name='" + getThreadName() + "' runnable=" + runnable + " lines="
            + lines.size()).append("\n");
      }
      boolean first = true;
      for (String line : lines) {
        buffer.append(line).append("\n");
        if (first && breadcrumbs != null) {
          for (String bline : breadcrumbs) {
            buffer.append(bline).append("\n");
          }
        }
        first = false;
      }
    }
create a stack with the given initial lines, reading the rest from the Reader
geode-core/src/main/java/org/apache/geode/internal/util/PluckStacks.java