Program: 51871
Project: 51871
Buggy source:
public void setup(org.dspace.content.Bitstream bitstream,ServletContext servletContext,String expand,Context context) throws SQLException {
  List<String> expandFields=new ArrayList<String>();
  if (expand != null) {
    expandFields=Arrays.asList(expand.split("String_Node_Str"));
  }
  if (bitstream.getBundles() != null & bitstream.getBundles().size() >= 0) {
    if (bitstreamService.getParentObject(context,bitstream).getType() == Constants.ITEM) {
      bundleName=bitstream.getBundles().get(0).getName();
    }
  }
  description=bitstream.getDescription();
  format=bitstreamService.getFormatDescription(context,bitstream);
  sizeBytes=bitstream.getSize();
  String path=new DSpace().getRequestService().getCurrentRequest().getHttpServletRequest().getContextPath();
  retrieveLink=path + "String_Node_Str" + bitstream.getID()+ "String_Node_Str";
  mimeType=bitstreamService.getFormat(context,bitstream).getMIMEType();
  sequenceId=bitstream.getSequenceID();
  CheckSum checkSum=new CheckSum();
  checkSum.setCheckSumAlgorith(bitstream.getChecksumAlgorithm());
  checkSum.setValue(bitstream.getChecksum());
  this.setCheckSum(checkSum);
  if (expandFields.contains("String_Node_Str") || expandFields.contains("String_Node_Str")) {
    parentObject=new DSpaceObject(bitstreamService.getParentObject(context,bitstream),servletContext);
  }
 else {
    this.addExpand("String_Node_Str");
  }
  if (expandFields.contains("String_Node_Str") || expandFields.contains("String_Node_Str")) {
    List<ResourcePolicy> tempPolicies=new ArrayList<ResourcePolicy>();
    List<Bundle> bundles=bitstream.getBundles();
    for (    Bundle bundle : bundles) {
      List<org.dspace.authorize.ResourcePolicy> bitstreamsPolicies=bundleService.getBitstreamPolicies(context,bundle);
      for (      org.dspace.authorize.ResourcePolicy policy : bitstreamsPolicies) {
        if (policy.getdSpaceObject().equals(bitstream)) {
          tempPolicies.add(new ResourcePolicy(policy));
        }
      }
    }
    policies=tempPolicies.toArray(new ResourcePolicy[0]);
  }
 else {
    this.addExpand("String_Node_Str");
  }
  if (!expandFields.contains("String_Node_Str")) {
    this.addExpand("String_Node_Str");
  }
}

Fixed version (ground truth):
public void setup(org.dspace.content.Bitstream bitstream,ServletContext servletContext,String expand,Context context) throws SQLException {
  List<String> expandFields=new ArrayList<String>();
  if (expand != null) {
    expandFields=Arrays.asList(expand.split("String_Node_Str"));
  }
  if (bitstream.getBundles() != null && !bitstream.getBundles().isEmpty()) {
    if (bitstreamService.getParentObject(context,bitstream).getType() == Constants.ITEM) {
      bundleName=bitstream.getBundles().get(0).getName();
    }
  }
  description=bitstream.getDescription();
  format=bitstreamService.getFormatDescription(context,bitstream);
  sizeBytes=bitstream.getSize();
  String path=new DSpace().getRequestService().getCurrentRequest().getHttpServletRequest().getContextPath();
  retrieveLink=path + "String_Node_Str" + bitstream.getID()+ "String_Node_Str";
  mimeType=bitstreamService.getFormat(context,bitstream).getMIMEType();
  sequenceId=bitstream.getSequenceID();
  CheckSum checkSum=new CheckSum();
  checkSum.setCheckSumAlgorith(bitstream.getChecksumAlgorithm());
  checkSum.setValue(bitstream.getChecksum());
  this.setCheckSum(checkSum);
  if (expandFields.contains("String_Node_Str") || expandFields.contains("String_Node_Str")) {
    parentObject=new DSpaceObject(bitstreamService.getParentObject(context,bitstream),servletContext);
  }
 else {
    this.addExpand("String_Node_Str");
  }
  if (expandFields.contains("String_Node_Str") || expandFields.contains("String_Node_Str")) {
    List<ResourcePolicy> tempPolicies=new ArrayList<ResourcePolicy>();
    List<Bundle> bundles=bitstream.getBundles();
    for (    Bundle bundle : bundles) {
      List<org.dspace.authorize.ResourcePolicy> bitstreamsPolicies=bundleService.getBitstreamPolicies(context,bundle);
      for (      org.dspace.authorize.ResourcePolicy policy : bitstreamsPolicies) {
        if (policy.getdSpaceObject().equals(bitstream)) {
          tempPolicies.add(new ResourcePolicy(policy));
        }
      }
    }
    policies=tempPolicies.toArray(new ResourcePolicy[0]);
  }
 else {
    this.addExpand("String_Node_Str");
  }
  if (!expandFields.contains("String_Node_Str")) {
    this.addExpand("String_Node_Str");
  }
}