Program: 5351
Project: 5351
Buggy source:
public int compareTo(A other){
  int comp=0;
  String this_att, other_att;
  if (getRole() == null)   this_att="String_Node_Str";
 else   this_att=getRole().getName();
  if (other.getRole() == null)   other_att="String_Node_Str";
 else   other_att=other.getRole().getName();
  comp=this_att.compareTo(other_att);
  if (comp == 0) {
    if (getEventType() == null)     this_att="String_Node_Str";
 else     this_att=getEventType().toString();
    if (other.getEventType() == null)     other_att="String_Node_Str";
 else     other_att=other.getEventType().toString();
    comp=this_att.compareTo(other_att);
  }
  if (comp == 0) {
    if (getAttributeType() == null)     this_att="String_Node_Str";
 else     this_att=getAttributeType().toString();
    if (other.getAttributeType() == null)     other_att="String_Node_Str";
 else     other_att=other.getAttributeType().toString();
    comp=this_att.compareTo(other_att);
  }
  if (comp == 0) {
    int this_off, other_off;
    if (getOffset() == null)     this_off=0;
 else     this_off=getOffset();
    if (other.getOffset() == null)     other_off=0;
 else     other_off=other.getOffset();
    comp=this_off - other_off;
  }
  if (comp == 0) {
    if (getParamOffset() == null && other.getParamOffset() == null)     comp=0;
 else     if (getParamOffset() != null && other.getParamOffset() != null)     comp=getParamOffset().compareTo(other.getParamOffset());
 else     comp=1;
  }
  if (comp == 0) {
    if (getKey() == null)     this_att="String_Node_Str";
 else     this_att=getKey().toString();
    if (other.getKey() == null)     other_att="String_Node_Str";
 else     other_att=other.getKey().toString();
    comp=this_att.compareTo(other_att);
  }
  if (comp == 0) {
    if (getParamKey() == null && other.getParamKey() == null)     comp=0;
 else     if (getParamKey() != null && other.getParamKey() != null)     comp=getParamKey().compareTo(other.getParamKey());
 else     comp=1;
  }
  if (comp != 0)   return 1;
 else   return 0;
}

Fixed version (ground truth):
public int compareTo(A other){
  int comp=0;
  String this_att, other_att;
  if (getRole() == null)   this_att="String_Node_Str";
 else   this_att=getRole().getName();
  if (other.getRole() == null)   other_att="String_Node_Str";
 else   other_att=other.getRole().getName();
  comp=this_att.compareTo(other_att);
  if (comp == 0) {
    if (getEventType() == null)     this_att="String_Node_Str";
 else     this_att=getEventType().toString();
    if (other.getEventType() == null)     other_att="String_Node_Str";
 else     other_att=other.getEventType().toString();
    comp=this_att.compareTo(other_att);
  }
  if (comp == 0) {
    if (getAttributeType() == null)     this_att="String_Node_Str";
 else     this_att=getAttributeType().toString();
    if (other.getAttributeType() == null)     other_att="String_Node_Str";
 else     other_att=other.getAttributeType().toString();
    comp=this_att.compareTo(other_att);
  }
  if (comp == 0) {
    int this_off, other_off;
    if (getOffset() == null)     this_off=0;
 else     this_off=getOffset();
    if (other.getOffset() == null)     other_off=0;
 else     other_off=other.getOffset();
    comp=this_off - other_off;
  }
  if (comp == 0) {
    if (getParamOffset() == null && other.getParamOffset() == null)     comp=0;
 else     if (getParamOffset() != null && other.getParamOffset() != null)     comp=getParamOffset().compareTo(other.getParamOffset());
 else     if (getParamOffset() == null)     comp=-1;
 else     comp=1;
  }
  if (comp == 0) {
    if (getKey() == null)     this_att="String_Node_Str";
 else     this_att=getKey().toString();
    if (other.getKey() == null)     other_att="String_Node_Str";
 else     other_att=other.getKey().toString();
    comp=this_att.compareTo(other_att);
  }
  if (comp == 0) {
    if (getParamKey() == null && other.getParamKey() == null)     comp=0;
 else     if (getParamKey() != null && other.getParamKey() != null)     comp=getParamKey().compareTo(other.getParamKey());
 else     if (getParamKey() == null)     comp=-1;
 else     comp=1;
  }
  return comp;
}