#vulnerable code 
                                private void initCommitAndTermFromLog() {
        DBIterator iterator = db.iterator();
        try {
            iterator.seekToLast();
            byte[] keyBytes = iterator.peekNext().getKey();
            commitIndex = new Integer(asString(keyBytes));

            //get the term from the serialized logentry
            byte[] entryBytes = iterator.peekNext().getValue();
            LogEntry entry = asLogEntry(entryBytes);
            this.currentTerm = entry.term;

        } finally {
            try {
                iterator.close();
            } catch (IOException e) {
                e.printStackTrace();
            }
        }
    } 
                            #location 11 
                            #vulnerability type NULL_DEREFERENCE
#fixed code
                                private void initCommitAndTermFromLog() throws Exception {
        DBIterator iterator = db.iterator();
        try {
            iterator.seekToLast();
            byte[] keyBytes = iterator.peekNext().getKey();
            commitIndex = new Integer(asString(keyBytes));

            //get the term from the serialized logentry
            byte[] entryBytes = iterator.peekNext().getValue();
            LogEntry entry =(LogEntry)Util.streamableFromByteBuffer(LogEntry.class, entryBytes);
            this.currentTerm = entry.term;

        } finally {
            try {
                iterator.close();
            } catch (IOException e) {
                e.printStackTrace();
            }
        }
    }