Program: 25563
Project: 25563
Buggy source:
private BoxMipmapGenerator validateNextLevel(final BoxMipmapGenerator boxMipmapGenerator,final int[][] expectedRowAndColumnPairs) throws Exception {
  final BoxMipmapGenerator nextLevelGenerator=boxMipmapGenerator.generateNextLevel();
  final int level=nextLevelGenerator.getSourceLevel();
  final List<File> missingFiles=new ArrayList<>();
  for (  final int[] rowAndColumn : expectedRowAndColumnPairs) {
    final File file=new File(boxDirectory,level + "String_Node_Str" + z+ "String_Node_Str"+ rowAndColumn[0]+ "String_Node_Str"+ rowAndColumn[1]+ "String_Node_Str");
    filesAndDirectoriesToDelete.add(file);
    if (!file.exists()) {
      missingFiles.add(file);
    }
    filesAndDirectoriesToDelete.add(new File(boxDirectory,level + "String_Node_Str" + z+ "String_Node_Str"+ rowAndColumn[0]));
  }
  filesAndDirectoriesToDelete.add(new File(boxDirectory,level + "String_Node_Str" + z));
  filesAndDirectoriesToDelete.add(new File(boxDirectory,String.valueOf(level)));
  Assert.assertTrue("String_Node_Str" + level + "String_Node_Str"+ missingFiles,missingFiles.isEmpty());
  final Path overviewDirPath=Paths.get(boxDirectory.getAbsolutePath(),"String_Node_Str");
  final File overviewFile=new File(overviewDirPath.toFile(),z + "String_Node_Str").getAbsoluteFile();
  final boolean isOverviewGenerated=boxMipmapGenerator.generateOverview(overviewWidth,layerBounds,overviewFile);
  filesAndDirectoriesToDelete.add(overviewFile);
  filesAndDirectoriesToDelete.add(overviewFile.getParentFile());
  Assert.assertFalse("String_Node_Str" + level,isOverviewGenerated);
  Assert.assertFalse("String_Node_Str" + overviewFile + "String_Node_Str"+ level,overviewFile.exists());
  return nextLevelGenerator;
}

Fixed version (ground truth):
private BoxMipmapGenerator validateNextLevel(final BoxMipmapGenerator boxMipmapGenerator,final int[][] expectedRowAndColumnPairs) throws Exception {
  final BoxMipmapGenerator nextLevelGenerator=boxMipmapGenerator.generateNextLevel();
  final int level=nextLevelGenerator.getSourceLevel();
  final List<File> missingFiles=new ArrayList<>();
  for (  final int[] rowAndColumn : expectedRowAndColumnPairs) {
    final File file=new File(boxDirectory,level + "String_Node_Str" + z+ "String_Node_Str"+ rowAndColumn[0]+ "String_Node_Str"+ rowAndColumn[1]+ "String_Node_Str");
    filesAndDirectoriesToDelete.add(file);
    if (!file.exists()) {
      missingFiles.add(file);
    }
    filesAndDirectoriesToDelete.add(new File(boxDirectory,level + "String_Node_Str" + z+ "String_Node_Str"+ rowAndColumn[0]));
  }
  filesAndDirectoriesToDelete.add(new File(boxDirectory,level + "String_Node_Str" + z));
  filesAndDirectoriesToDelete.add(new File(boxDirectory,String.valueOf(level)));
  Assert.assertTrue("String_Node_Str" + level + "String_Node_Str"+ missingFiles,missingFiles.isEmpty());
  final Path overviewDirPath=Paths.get(boxDirectory.getAbsolutePath(),"String_Node_Str");
  final File overviewFile=new File(overviewDirPath.toFile(),z + "String_Node_Str").getAbsoluteFile();
  final boolean isOverviewGenerated=boxMipmapGenerator.generateOverview(overviewWidth,stackBounds,overviewFile);
  filesAndDirectoriesToDelete.add(overviewFile);
  filesAndDirectoriesToDelete.add(overviewFile.getParentFile());
  Assert.assertFalse("String_Node_Str" + level,isOverviewGenerated);
  Assert.assertFalse("String_Node_Str" + overviewFile + "String_Node_Str"+ level,overviewFile.exists());
  return nextLevelGenerator;
}