Java Code Examples for org.iq80.leveldb.DBIterator#close()

The following examples show how to use org.iq80.leveldb.DBIterator#close() . You can vote up the ones you like or vote down the ones you don't like, and go to the original project or source file by following the links above each example. You may check out the related API usage on the sidebar.

Example 1

Source File: SelectLevelDBData.java From gsc-core with GNU Lesser General Public License v3.0

6 votes

public static void data(String dataName) {
    Options options = new Options();
    //options.createIfMissing(true);
    DB db = null;
    try {
        System.out.println("Path: " + path + dataName);
        db = factory.open(new File(path + dataName), options);

        logger.info("---------------------------------------------");
        System.out.println();
        DBIterator iterator = db.iterator();
        iterator.seekToFirst();
        int count = 0;
        while (iterator.hasNext()) {
            count++;
            switch (dataName) {
                case "properties":
                    properties(iterator.peekNext().getKey(), iterator.peekNext().getValue());
                    break;
                case "peers":
                    peers(iterator.peekNext().getKey(), iterator.peekNext().getValue());
                    break;
                case "nodes":
                    peers(iterator.peekNext().getKey(), iterator.peekNext().getValue());
                    break;
                default:
                    break;
            }
            iterator.next();
        }
        iterator.close();
        System.out.println(dataName + " Num: " + count);
        System.out.println();
        logger.info("---------------------------------------------");

        db.close();
    } catch (IOException e) {
        e.printStackTrace();
    }
}

Example 2

Source File: LevelDbUtil.java From mcg-helper with Apache License 2.0

6 votes

public static void print() throws IOException {
    //iterator，遍历，顺序读
    //读取当前snapshot，快照，读取期间数据的变更，不会反应出来       
    Snapshot snapshot = db.getSnapshot();
    //读选项        
    ReadOptions readOptions = new ReadOptions();
    readOptions.fillCache(false);//遍历中swap出来的数据，不应该保存在memtable中。        
    readOptions.snapshot(snapshot);//默认snapshot为当前。        
    DBIterator iterator = db.iterator(readOptions);
    while (iterator.hasNext()) {
        Map.Entry<byte[],byte[]> item = iterator.next();
        String key = new String(item.getKey(), Constants.CHARSET);
        String value = new String(item.getValue(), Constants.CHARSET);
        logger.debug("key:{}，value:{}", key, value);
    }
    iterator.close();
}

Example 3

Source File: LevelDbStore.java From dubbox with Apache License 2.0

4 votes

public static void main(String[] args) throws Exception {
		Kryo kryo = new Kryo();
		kryo.setReferences(false);
		kryo.setRegistrationRequired(false);
		kryo.setInstantiatorStrategy(new DefaultInstantiatorStrategy(new StdInstantiatorStrategy()));
//		kryo.register(Transaction.class);
//		kryo.register(Xid.class);
//		kryo.register(TransactionType.class);
//		kryo.register(TransactionStatus.class);
//		kryo.register(Participant.class);
		
//		Output output = new Output(new ByteArrayOutputStream());//new Output(new FileOutputStream("file.bin"));
//		
//		DefaultTransaction defaultTransaction = new DefaultTransaction();
//		defaultTransaction.setXid(new DefaultXid("1", "2", "3"));
//		
//		kryo.writeObject(output, defaultTransaction);
//		output.flush();
//		output.close();
		
		Options options = new Options();
		options.createIfMissing(true);
		options.cacheSize(100 * 1048576); // 100MB cache
		options.logger(new org.iq80.leveldb.Logger() {
			public void log(String message) {
				TransactionLog.REPOSITORY.info(message);
			}
		});
		DB db = Iq80DBFactory.factory.open(new File("txtreedb"), options);
		
//		String stats = db.getProperty("leveldb.stats");
//		System.out.println(stats);
		
		DBIterator iterator = null;
		try {
			iterator = db.iterator();
			for(iterator.seekToFirst(); iterator.hasNext(); iterator.next()) {
				String key = Iq80DBFactory.asString(iterator.peekNext().getKey());
				Transaction value = (Transaction) SerializationUtil.deserialize(iterator.peekNext().getValue());
				
				System.out.println(key+" = "+value);
			}
		} finally {
			if (iterator != null) {
				iterator.close();
			}
		}

//		String transactionId = "f282205a-e794-4bda-83a2-bb28b8839cad";
//		Input input = new Input(db.get(Iq80DBFactory.bytes(transactionId)));
//		Transaction transaction = (Transaction) kryo.readClassAndObject(input);
//		System.out.println(transaction);
	}

Example 4

Source File: StandaloneStoreClient.java From warp10-platform with Apache License 2.0

4 votes

@Override
public long delete(WriteToken token, Metadata metadata, long start, long end) throws IOException {
  
  //
  // Regen classId/labelsId
  //
  
  // 128BITS
  metadata.setLabelsId(GTSHelper.labelsId(this.keystore.getKey(KeyStore.SIPHASH_LABELS), metadata.getLabels()));
  metadata.setClassId(GTSHelper.classId(this.keystore.getKey(KeyStore.SIPHASH_CLASS), metadata.getName()));

  //
  // Retrieve an iterator
  //
  
  DBIterator iterator = this.db.iterator();
  //
  // Seek the most recent key
  //
  
  // 128BITS
  byte[] bend = new byte[Constants.HBASE_RAW_DATA_KEY_PREFIX.length + 8 + 8 + 8];
  ByteBuffer bb = ByteBuffer.wrap(bend).order(ByteOrder.BIG_ENDIAN);
  bb.put(Constants.HBASE_RAW_DATA_KEY_PREFIX);
  bb.putLong(metadata.getClassId());
  bb.putLong(metadata.getLabelsId());
  bb.putLong(Long.MAX_VALUE - end);

  iterator.seek(bend);
  
  byte[] bstart = new byte[bend.length];
  bb = ByteBuffer.wrap(bstart).order(ByteOrder.BIG_ENDIAN);
  bb.put(Constants.HBASE_RAW_DATA_KEY_PREFIX);
  bb.putLong(metadata.getClassId());
  bb.putLong(metadata.getLabelsId());
  bb.putLong(Long.MAX_VALUE - start);
  
  //
  // Scan the iterator, deleting keys if they are between start and end
  //
  
  long count = 0L;
  
  WriteBatch batch = this.db.createWriteBatch();
  int batchsize = 0;
  
  WriteOptions options = new WriteOptions().sync(1.0 == syncrate);
              
  while (iterator.hasNext()) {
    Entry<byte[],byte[]> entry = iterator.next();

    if (Bytes.compareTo(entry.getKey(), bend) >= 0 && Bytes.compareTo(entry.getKey(), bstart) <= 0) {
      batch.delete(entry.getKey());
      batchsize++;
      
      if (MAX_DELETE_BATCHSIZE <= batchsize) {
        if (syncwrites) {
          options = new WriteOptions().sync(Math.random() < syncrate);
        }
        this.db.write(batch, options);
        batch.close();
        batch = this.db.createWriteBatch();
        batchsize = 0;
      }
      //this.db.delete(entry.getKey());
      count++;
    } else {
      break;
    }
  }
  
  if (batchsize > 0) {
    if (syncwrites) {
      options = new WriteOptions().sync(Math.random() < syncrate);
    }
    this.db.write(batch, options);
  }

  iterator.close();
  batch.close();
  
  return count;
}

Example 5