#vulnerable code 
                                private File[] readSeedFiles() {
        if (this.inputDirectory == null) {
            return new File[0];
        }

        ArrayList<File> seedFilesArray = new ArrayList<>();
        File[] allFiles = this.inputDirectory.listFiles();
        for (int i = 0; i < allFiles.length; i++) {
            if (allFiles[i].isFile()) {
                seedFilesArray.add(allFiles[i]);
            }
        }
        File[] seedFiles = seedFilesArray.toArray(new File[seedFilesArray.size()]);
        return seedFiles;
    } 
                            #location 8 
                            #vulnerability type NULL_DEREFERENCE
#fixed code
                                private File[] readSeedFiles() {
        if (this.inputDirectory == null) {
            return new File[0];
        }

        ArrayList<File> seedFilesArray = new ArrayList<>();
        File[] allFiles = this.inputDirectory.listFiles();
        if (allFiles == null) {
            // this means the directory doesn't exist
            return new File[0];
        }
        for (int i = 0; i < allFiles.length; i++) {
            if (allFiles[i].isFile()) {
                seedFilesArray.add(allFiles[i]);
            }
        }
        File[] seedFiles = seedFilesArray.toArray(new File[seedFilesArray.size()]);
        return seedFiles;
    }