Program: 92877
Project: 92877
Buggy source:
public void processGroups(InputLine input,Matcher matcher){
  for (int i=0; i < input.columns.size(); i++) {
    InputData column=input.columns.get(i);
    if (i < matcher.groupCount() && matcher.group(i + 1) != null) {
      String value=matcher.group(i + 1).trim();
      if (value.length() == 0) {
        continue;
      }
      String name=column.name;
      if (column.action == CustomTxtTraceDefinition.ACTION_SET) {
        fData.put(name,value);
        if (name.equals(CustomTxtTraceDefinition.TAG_TIMESTAMP)) {
          fData.put(TIMESTAMP_INPUT_FORMAT_KEY,column.format);
        }
      }
 else       if (column.action == CustomTxtTraceDefinition.ACTION_APPEND) {
        String s=fData.get(name);
        if (s != null) {
          fData.put(name,s + value);
        }
 else {
          fData.put(name,value);
        }
        if (name.equals(CustomTxtTraceDefinition.TAG_TIMESTAMP)) {
          String timeStampInputFormat=fData.get(TIMESTAMP_INPUT_FORMAT_KEY);
          if (timeStampInputFormat != null) {
            fData.put(TIMESTAMP_INPUT_FORMAT_KEY,timeStampInputFormat + column.format);
          }
 else {
            fData.put(TIMESTAMP_INPUT_FORMAT_KEY,column.format);
          }
        }
      }
 else       if (column.action == CustomTxtTraceDefinition.ACTION_APPEND_WITH_SEPARATOR) {
        String s=fData.get(name);
        if (s != null) {
          fData.put(name,s + "String_Node_Str" + value);
        }
 else {
          fData.put(name,value);
        }
        if (name.equals(CustomTxtTraceDefinition.TAG_TIMESTAMP)) {
          String timeStampInputFormat=fData.get(TIMESTAMP_INPUT_FORMAT_KEY);
          if (timeStampInputFormat != null) {
            fData.put(TIMESTAMP_INPUT_FORMAT_KEY,timeStampInputFormat + "String_Node_Str" + column.format);
          }
 else {
            fData.put(TIMESTAMP_INPUT_FORMAT_KEY,column.format);
          }
        }
      }
    }
  }
}

Fixed version (ground truth):
public void processGroups(InputLine input,Matcher matcher){
  if (input.columns == null) {
    return;
  }
  for (int i=0; i < input.columns.size(); i++) {
    InputData column=input.columns.get(i);
    if (i < matcher.groupCount() && matcher.group(i + 1) != null) {
      String value=matcher.group(i + 1).trim();
      if (value.length() == 0) {
        continue;
      }
      String name=column.name;
      if (column.action == CustomTxtTraceDefinition.ACTION_SET) {
        fData.put(name,value);
        if (name.equals(CustomTxtTraceDefinition.TAG_TIMESTAMP)) {
          fData.put(TIMESTAMP_INPUT_FORMAT_KEY,column.format);
        }
      }
 else       if (column.action == CustomTxtTraceDefinition.ACTION_APPEND) {
        String s=fData.get(name);
        if (s != null) {
          fData.put(name,s + value);
        }
 else {
          fData.put(name,value);
        }
        if (name.equals(CustomTxtTraceDefinition.TAG_TIMESTAMP)) {
          String timeStampInputFormat=fData.get(TIMESTAMP_INPUT_FORMAT_KEY);
          if (timeStampInputFormat != null) {
            fData.put(TIMESTAMP_INPUT_FORMAT_KEY,timeStampInputFormat + column.format);
          }
 else {
            fData.put(TIMESTAMP_INPUT_FORMAT_KEY,column.format);
          }
        }
      }
 else       if (column.action == CustomTxtTraceDefinition.ACTION_APPEND_WITH_SEPARATOR) {
        String s=fData.get(name);
        if (s != null) {
          fData.put(name,s + "String_Node_Str" + value);
        }
 else {
          fData.put(name,value);
        }
        if (name.equals(CustomTxtTraceDefinition.TAG_TIMESTAMP)) {
          String timeStampInputFormat=fData.get(TIMESTAMP_INPUT_FORMAT_KEY);
          if (timeStampInputFormat != null) {
            fData.put(TIMESTAMP_INPUT_FORMAT_KEY,timeStampInputFormat + "String_Node_Str" + column.format);
          }
 else {
            fData.put(TIMESTAMP_INPUT_FORMAT_KEY,column.format);
          }
        }
      }
    }
  }
}