Java Blob类代码示例

import com.google.appengine.api.datastore.Blob; //导入依赖的package包/类
public Entity buildEntityFromPersistentObject(final P persistentObject, final DAO<P> dao) {
    if (persistentObject == null) {
        return null;
    }

    final Entity anEntity = new Entity(dao.getEntityName(), persistentObject.getId());

    final byte[] binaryData = objectHolderSerializer.serialize(persistentObject.getDataObject(), true);

    if (binaryData.length > 1000000) {
        throw new RuntimeException("BinaryData length for object [" + persistentObject + "] is bigger than permitted: " + binaryData.length);
    }

    anEntity.setUnindexedProperty(DATA_CONTAINER_PROPERTY, new Blob(binaryData));

    for (final PropertyMeta propertyMeta : persistentObject.getPropertiesMetadata().values()) {
        if (propertyMeta.isIndexable()) {
            anEntity.setProperty(propertyMeta.getPropertyName(), propertyMeta.get());
        }
    }
    return anEntity;
}
 

import com.google.appengine.api.datastore.Blob; //导入依赖的package包/类
public static Resource load(final String id, final boolean exceptionOnNotFound) {
    Resource result = (Resource) CacheStrategy.APPLICATION_CACHE.get().get(ENTITY_NAME + id);

    if (result == null) {
        final Entity entity = new RetryingHandler().tryDSGet(DAO.buildKey(ENTITY_NAME, id));

        if (entity != null) {
            result = new Resource();
            result.id = id;
            result.type = (String) entity.getProperty("type");

            final Blob binaryData = (Blob) entity.getProperty("bdata");
            result.rawValue = binaryData == null ? null : binaryData.getBytes();
        }
    }

    if (result == null && exceptionOnNotFound) {
        throw new RuntimeException("Could not find resource with key [" + id + "]");
    }
    return result;
}
 

import com.google.appengine.api.datastore.Blob; //导入依赖的package包/类
public void save(final boolean saveAsync) {
    validateSize();

    final Entity anEntity = new Entity(ENTITY_NAME, id);

    if (type != null) {
        anEntity.setProperty("type", type);
    }
    if (rawValue != null) {
        anEntity.setUnindexedProperty("bdata", new Blob(rawValue));
    }

    final RetryingHandler retryingHandler = new RetryingHandler();

    if (saveAsync) {
        retryingHandler.tryDSPutAsync(anEntity);
    } else {
        retryingHandler.tryDSPut(anEntity);
    }
    CacheStrategy.APPLICATION_CACHE.get().put(ENTITY_NAME + id, this);
}
 

import com.google.appengine.api.datastore.Blob; //导入依赖的package包/类
public  List<Event> GetEventsForAggregate(UUID aggregateId)
{
	logger.log(Level.INFO, ComplexLogMessages.eventStoreReadMessage("AggregateId", aggregateId.toString()));
	
	DatastoreService datastore = DatastoreServiceFactory.getDatastoreService();
	Key aggregateKey = KeyFactory.createKey("WishListEvents", aggregateId.toString());
	
	Query query = new Query("WishListEvent", aggregateKey);
    List<Entity> storedEvents = datastore.prepare(query).asList(FetchOptions.Builder.withDefaults());
    
    ArrayList<Event> eventData = new ArrayList<Event>();
	for(Entity e : storedEvents)
	{
		eventData.add(PropertyConverter.convertBlobToObject(Event.class, (Blob)e.getProperty("EventData")));
	}
	
	if(eventData.isEmpty())
	{
		logger.log(Level.WARNING, ComplexLogMessages.exceptionMessage("AggregateNotFoundException", "Aggregate was not found."));
		throw new AggregateNotFoundException("Aggregate was not found.");
	}
	
    return eventData;
}
 

import com.google.appengine.api.datastore.Blob; //导入依赖的package包/类
@Override
public List<WishListDto> GetWishLists() 
{
	logger.log(Level.INFO, ComplexLogMessages.queryFacadeMessage("GetWishLists"));
   	
	DatastoreService datastore = DatastoreServiceFactory.getDatastoreService();
   	Key aggregateKey = KeyFactory.createKey("WishListsView", "WishListsView");
   	
   	Query query = new Query("WishListDto", aggregateKey);
       List<Entity> storedEntities = datastore.prepare(query).asList(FetchOptions.Builder.withDefaults());
       
       List<WishListDto> wishLists = new ArrayList<WishListDto>();
       
       for(Entity e : storedEntities)
       {
       	wishLists.add(PropertyConverter.convertBlobToObject(WishListDto.class, (Blob)e.getProperty("WishListDto")));
       }
	return wishLists;
}
 

import com.google.appengine.api.datastore.Blob; //导入依赖的package包/类
public void handle(NameOfWishListChangedEvent event)
{
	logger.log(Level.INFO, ComplexLogMessages.eventHandlerMessage(event.getClass().getSimpleName(), "Id", event.Id.toString(), "NewName", event.NewName, "Version", "" + event.Version));
   	
	DatastoreService datastore = DatastoreServiceFactory.getDatastoreService();
   	Key aggregateKey = KeyFactory.createKey("WishListsView", "WishListsView");
   	
   	Query query = new Query("WishListDto", aggregateKey);
       List<Entity> storedEntities = datastore.prepare(query).asList(FetchOptions.Builder.withDefaults());
       
       for(Entity e : storedEntities)
       {
       	if(UUID.fromString((String)e.getProperty("Id")).equals(event.Id))
       	{
       		WishListDto wishListDto = PropertyConverter.convertBlobToObject(WishListDto.class, (Blob)e.getProperty("WishListDto"));
       		wishListDto.setName(event.NewName);
       		wishListDto.setVersion(event.Version);
       		
       		e.setProperty("WishListDto", PropertyConverter.convertObjectToBlob(wishListDto));
       		datastore.put(e);
       		break;
       	}
       }
}
 

import com.google.appengine.api.datastore.Blob; //导入依赖的package包/类
public static <T>Blob convertObjectToBlob(T o)
  {
  	
  	try 
  	{
  		ByteArrayOutputStream bos = new ByteArrayOutputStream();
      	ObjectOutput out = new ObjectOutputStream(bos);
	out.writeObject(o);
   	return new Blob(bos.toByteArray());
} 
  	catch (IOException e) 
  	{
	e.printStackTrace();
	return null;
}
  }
 

import com.google.appengine.api.datastore.Blob; //导入依赖的package包/类
@SuppressWarnings("unchecked")
public static <T>T convertBlobToObject(Class<T> clazz, Blob b)
   {
   	
   	try 
   	{
   		ByteArrayInputStream bos = new ByteArrayInputStream(b.getBytes());
   		ObjectInputStream is = new ObjectInputStream(bos);
   	    return (T) is.readObject();
	} 
   	catch (IOException | ClassNotFoundException e) 
   	{
		e.printStackTrace();
		return null;
	}
   }
 

import com.google.appengine.api.datastore.Blob; //导入依赖的package包/类
@Test
public void testSize() {
    String kind = kindName + "-size";
    int recordSize = (1000 * 1000);  // Max. 1000000.
    byte[] filledRec = new byte[recordSize];
    Arrays.fill(filledRec, (byte) 0x41);
    Blob bigBlob = new Blob(filledRec);
    assertEquals(recordSize, bigBlob.getBytes().length);
    Entity eBlob = new Entity(kind, rootKey);
    eBlob.setProperty("blobProp", bigBlob);
    service.put(eBlob);

    recordSize = 500 ;  // Max. 500.
    filledRec = new byte[recordSize];
    Arrays.fill(filledRec, (byte) 0x41);
    ShortBlob shortBlob = new ShortBlob(filledRec);
    assertEquals(recordSize, shortBlob.getBytes().length);
    Entity eShortBlob = new Entity(kind, rootKey);
    eShortBlob.setProperty("byteStrProp", shortBlob);
    service.put(eShortBlob);

    service.delete(eBlob.getKey(), eShortBlob.getKey());
}
 

import com.google.appengine.api.datastore.Blob; //导入依赖的package包/类
private Entity createEntityForPut(I_BlobKey keySource, I_Blob blob) throws BlobException
{
	Key keyObject = KeyFactory.createKey(blob.getKind(), keySource.createBlobKey(blob));
	Entity entity = new Entity(keyObject);
	byte[] blobBytes = U_Blob.convertToBytes(blob);
	Blob blobData = new Blob(blobBytes);
	entity.setUnindexedProperty(S_Blob.DATA_FIELD_NAME, blobData);
	
	Map<String, Object> queryableProperties = blob.getQueryableProperties();
	
	if( queryableProperties != null )
	{
		for( String key : queryableProperties.keySet() )
		{
			entity.setProperty(key, queryableProperties.get(key));
		}
	}
	
	return entity;
}
 

import com.google.appengine.api.datastore.Blob; //导入依赖的package包/类
private static SimpleModule getWriteBlobAsBase64Module() {
  JsonSerializer<Blob> dateSerializer = new JsonSerializer<Blob>() {
    @Override
    public void serialize(Blob value, JsonGenerator jgen, SerializerProvider provider)
        throws IOException {
      byte[] bytes = value.getBytes();
      jgen.writeBinary(bytes, 0, bytes.length);
    }
  };
  SimpleModule writeBlobAsBase64Module = new SimpleModule("writeBlobAsBase64Module",
      new Version(1, 0, 0, null, null, null));
  writeBlobAsBase64Module.addSerializer(Blob.class, dateSerializer);
  return writeBlobAsBase64Module;
}
 

import com.google.appengine.api.datastore.Blob; //导入依赖的package包/类
@Test
public void testReadBlobParameter() throws Exception {
  Method method =
      TestEndpoint.class.getDeclaredMethod("doBlob", Blob.class);
  Object[] params = readParameters("{\"blob\":\"AQIDBA==\"}", method);

  assertEquals(1, params.length);
  assertThat(((Blob) params[0]).getBytes()).isEqualTo(new byte[]{1, 2, 3, 4});
}
 

import com.google.appengine.api.datastore.Blob; //导入依赖的package包/类
@SuppressWarnings("unused")
public void testBlobAsBase64() throws Exception {
  Object value = new Object() {
    public Blob getBlob() {
      return new Blob(new byte[]{1, 2, 3, 4});
    }
  };
  ObjectNode output = ObjectMapperUtil.createStandardObjectMapper()
      .readValue(writeToResponse(value), ObjectNode.class);
  assertEquals("AQIDBA==", output.path("blob").asText());
}
 

import com.google.appengine.api.datastore.Blob; //导入依赖的package包/类
@Override
public Entity toEntity() {
  Entity entity = toProtoEntity();
  entity.setUnindexedProperty(SHARD_ID_PROPERTY, shardId);
  entity.setUnindexedProperty(VALUE_PROPERTY, new Blob(value));
  return entity;
}
 

import com.google.appengine.api.datastore.Blob; //导入依赖的package包/类
public ExceptionRecord(Entity entity) {
  super(entity);
  Blob serializedExceptionBlob = (Blob) entity.getProperty(EXCEPTION_PROPERTY);
  byte[] serializedException = serializedExceptionBlob.getBytes();
  try {
    exception = (Throwable) SerializationUtils.deserialize(serializedException);
  } catch (IOException e) {
    throw new RuntimeException("Failed to deserialize exception for " + getKey(), e);
  }
}