### Question:
SafeReader { public Collection<String> getMesasurementFiles(){ Collection <String>mesaurementFiles=new ArrayList<String>(); String fp=safe.getFilePath(); Collection<DataObject> dataObj=safe.getDataObjects(); Iterator<DataObject> iii=dataObj.iterator(); while(iii.hasNext()){ DataObject dob=iii.next(); if(dob.getRepID().equalsIgnoreCase("s1Level1MeasurementSchema")){ try{ System.out.println(dob.getRepID()); List<ByteStream> bytesStream=dob.getByteStreams(); for(int i=0;i<bytesStream.size();i++){ Reference ref=bytesStream.get(i).getFileLocations2().iterator().next().getReference(); String filePath=ref.getHref(); if(filePath.startsWith(".")) filePath=filePath.substring(2); StringBuilder build=new StringBuilder(fp).append(filePath); mesaurementFiles.add(build.toString()); System.out.println(build); } } catch (Exception e) { e.printStackTrace(); } } } return mesaurementFiles; } SafeReader(String safePath); Collection <MetadataObject> getMetadataObjects(); Collection <DataObject> getDataObjects(); Collection<String> getMesasurementFiles(); void readGeneralProductInformation(); void getPolarizations();  }### Answer:
@Test public void testGetMesasurementFiles() { try { SafeReader safeReader=new SafeReader(safeFile); Collection<String> files=safeReader.getMesasurementFiles(); assertNotNull(files); for(String f:files){ assertTrue(new File(f).exists()); } } catch (IllegalArgumentException | IOException e) { fail(e.getMessage()); } }