com.google.cloud.datastore.Datastore.newTransaction()方法的使用及代码示例

x33g5p2x  于2022-01-18 转载在 其他  
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本文整理了Java中com.google.cloud.datastore.Datastore.newTransaction()方法的一些代码示例，展示了Datastore.newTransaction()的具体用法。这些代码示例主要来源于Github/Stackoverflow/Maven等平台，是从一些精选项目中提取出来的代码，具有较强的参考意义，能在一定程度帮忙到你。Datastore.newTransaction()方法的具体详情如下：
包路径：com.google.cloud.datastore.Datastore
类名称：Datastore
方法名：newTransaction

Datastore.newTransaction介绍

[英]Returns a new Datastore transaction.
[中]返回一个新的数据存储事务。

代码示例

代码示例来源：origin: google/data-transfer-project

@Override
public <T extends DataModel> void create(UUID jobId, String key, T model) throws IOException {
 Preconditions.checkNotNull(jobId);
 Transaction transaction = datastore.newTransaction();
 Key fullKey = getDataKey(jobId, key);
 Entity shouldNotExist = transaction.get(fullKey);
 if (shouldNotExist != null) {
  transaction.rollback();
  throw new IOException(
    "Record already exists for key: " + fullKey.getName() + ". Record: " + shouldNotExist);
 }
 String serialized = objectMapper.writeValueAsString(model);
 Entity entity = Entity.newBuilder(fullKey)
   .set(CREATED_FIELD, Timestamp.now())
   .set(model.getClass().getName(), serialized)
   .build();
 try {
  transaction.put(entity);
 } catch (DatastoreException e) {
  throw new IOException(
    "Could not create initial record for jobID: " + jobId + ". Record: " + entity, e);
 }
 transaction.commit();
}

代码示例来源：origin: google/data-transfer-project

@Override
public <T extends DataModel> void update(UUID jobId, String key, T model) {
 Transaction transaction = datastore.newTransaction();
 Key entityKey = getDataKey(jobId, key);
 try {
  Entity previousEntity = transaction.get(entityKey);
  if (previousEntity == null) {
   throw new IOException("Could not find record for data key: " + entityKey.getName());
  }
  String serialized = objectMapper.writeValueAsString(model);
  Entity entity = Entity.newBuilder(entityKey)
    .set(CREATED_FIELD, Timestamp.now())
    .set(model.getClass().getName(), serialized)
    .build();
  transaction.put(entity);
  transaction.commit();
 } catch (IOException t) {
  transaction.rollback();
  throw new RuntimeException("Failed atomic update of key: " + key, t);
 }
}

代码示例来源：origin: google/data-transfer-project

/**
 * Inserts a new {@link PortabilityJob} keyed by {@code jobId} in Datastore.
 *
 * <p>To update an existing {@link PortabilityJob} instead, use {@link JobStore#update}.
 *
 * @throws IOException if a job already exists for {@code jobId}, or if there was a different
 * problem inserting the job.
 */
@Override
public void createJob(UUID jobId, PortabilityJob job) throws IOException {
 Preconditions.checkNotNull(jobId);
 Transaction transaction = datastore.newTransaction();
 Entity shouldNotExist = transaction.get(getKey(jobId));
 if (shouldNotExist != null) {
  transaction.rollback();
  throw new IOException(
    "Record already exists for jobID: " + jobId + ". Record: " + shouldNotExist);
 }
 Entity entity = createEntity(jobId, job.toMap());
 try {
  transaction.put(entity);
 } catch (DatastoreException e) {
  transaction.rollback();
  throw new IOException(
    "Could not create initial record for jobID: " + jobId + ". Record: " + entity, e);
 }
 transaction.commit();
}

代码示例来源：origin: googleapis/google-cloud-java

Transaction tx = datastore.newTransaction();
Object request;
try {

代码示例来源：origin: google/data-transfer-project

throws IOException {
Preconditions.checkNotNull(jobId);
Transaction transaction = datastore.newTransaction();
Key key = getKey(jobId);

代码示例来源：origin: googleapis/google-cloud-java

@Override
 public T call() throws DatastoreException {
  transaction = datastore.newTransaction(options);
  try {
   T value = callable.run(transaction);
   transaction.commit();
   return value;
  } catch (Exception ex) {
   transaction.rollback();
   throw DatastoreException.propagateUserException(ex);
  } finally {
   if (transaction.isActive()) {
    transaction.rollback();
   }
   if (options != null
     && options.getModeCase().equals(TransactionOptions.ModeCase.READ_WRITE)) {
    setPrevTransactionId(transaction.getTransactionId());
   }
  }
 }
}

代码示例来源：origin: objectify/objectify

@Override
  public AsyncTransaction newTransaction(final Runnable afterCommit) {
    return new AsyncTransactionImpl(datastore.newTransaction(), afterCommit);
  }
}

代码示例来源：origin: googleapis/google-cloud-java

@Test
public void testNewTransactionCommit() {
 Transaction transaction = datastore.newTransaction();
 transaction.add(ENTITY3);
 Entity entity2 = Entity.newBuilder(ENTITY2).clear().setNull("bla").build();
 transaction.update(entity2);
 transaction.delete(KEY1);
 transaction.commit();
 List<Entity> list = datastore.fetch(KEY1, KEY2, KEY3);
 assertNull(list.get(0));
 assertEquals(entity2, list.get(1));
 assertEquals(ENTITY3, list.get(2));
 assertEquals(3, list.size());
 try {
  transaction.commit();
  fail("Expecting a failure");
 } catch (DatastoreException ex) {
  // expected to fail
 }
 try {
  transaction.rollback();
  fail("Expecting a failure");
 } catch (DatastoreException ex) {
  // expected to fail
 }
 verifyNotUsable(transaction);
}

代码示例来源：origin: googleapis/google-cloud-java

@Test
public void testTransactionWithRead() {
 Transaction transaction = datastore.newTransaction();
 assertNull(transaction.get(KEY3));
 transaction.add(ENTITY3);
 transaction.commit();
 assertEquals(ENTITY3, datastore.get(KEY3));
 transaction = datastore.newTransaction();
 assertEquals(ENTITY3, transaction.get(KEY3));
 // update entity3 during the transaction
 datastore.put(Entity.newBuilder(ENTITY3).clear().build());
 transaction.update(ENTITY2);
 try {
  transaction.commit();
  fail("Expecting a failure");
 } catch (DatastoreException expected) {
  assertEquals("ABORTED", expected.getReason());
 }
}

代码示例来源：origin: googleapis/google-cloud-java

@Test
public void testNewTransactionRollback() {
 Transaction transaction = datastore.newTransaction();
 transaction.add(ENTITY3);
 Entity entity2 =
   Entity.newBuilder(ENTITY2)
     .clear()
     .setNull("bla")
     .set("list3", StringValue.of("bla"), StringValue.newBuilder("bla").build())
     .build();
 transaction.update(entity2);
 transaction.delete(KEY1);
 transaction.rollback();
 transaction.rollback(); // should be safe to repeat rollback calls
 try {
  transaction.commit();
  fail("Expecting a failure");
 } catch (DatastoreException ex) {
  // expected to fail
 }
 verifyNotUsable(transaction);
 List<Entity> list = datastore.fetch(KEY1, KEY2, KEY3);
 assertEquals(ENTITY1, list.get(0));
 assertEquals(ENTITY2, list.get(1));
 assertNull(list.get(2));
 assertEquals(3, list.size());
}

代码示例来源：origin: googleapis/google-cloud-java

@Test
public void testNewTransactionRollback() {
 Transaction transaction = DATASTORE.newTransaction();
 transaction.add(ENTITY3);
 Entity entity2 =
   Entity.newBuilder(ENTITY2)
     .clear()
     .setNull("bla")
     .set("list3", StringValue.of("bla"), StringValue.newBuilder("bla").build())
     .build();
 transaction.update(entity2);
 transaction.delete(KEY1);
 transaction.rollback();
 transaction.rollback(); // should be safe to repeat rollback calls
 try {
  transaction.commit();
  fail("Expecting a failure");
 } catch (DatastoreException expected) {
  assertEquals("FAILED_PRECONDITION", expected.getReason());
 }
 List<Entity> list = DATASTORE.fetch(KEY1, KEY2, KEY3);
 assertEquals(ENTITY1, list.get(0));
 assertEquals(ENTITY2, list.get(1));
 assertNull(list.get(2));
 assertEquals(3, list.size());
}

代码示例来源：origin: googleapis/google-cloud-java

@Test
public void testNewTransactionCommit() {
 Transaction transaction = DATASTORE.newTransaction();
 transaction.add(ENTITY3);
 Entity entity2 = Entity.newBuilder(ENTITY2).clear().setNull("bla").build();
 transaction.update(entity2);
 transaction.delete(KEY1);
 transaction.commit();
 assertFalse(transaction.isActive());
 List<Entity> list = DATASTORE.fetch(KEY1, KEY2, KEY3);
 assertNull(list.get(0));
 assertEquals(entity2, list.get(1));
 assertEquals(ENTITY3, list.get(2));
 assertEquals(3, list.size());
 try {
  transaction.commit();
  fail("Expecting a failure");
 } catch (DatastoreException expected) {
  assertEquals("FAILED_PRECONDITION", expected.getReason());
 }
 try {
  transaction.rollback();
  fail("Expecting a failure");
 } catch (DatastoreException expected) {
  assertEquals("FAILED_PRECONDITION", expected.getReason());
 }
}

代码示例来源：origin: googleapis/google-cloud-java

@Test
public void testTransactionWithRead() {
 Transaction transaction = DATASTORE.newTransaction();
 assertNull(transaction.get(KEY3));
 transaction.add(ENTITY3);
 transaction.commit();
 assertEquals(ENTITY3, DATASTORE.get(KEY3));
 transaction = DATASTORE.newTransaction();
 assertEquals(ENTITY3, transaction.get(KEY3));
 // update entity3 during the transaction
 DATASTORE.put(Entity.newBuilder(ENTITY2).clear().set("from", "datastore").build());
 transaction.update(Entity.newBuilder(ENTITY2).clear().set("from", "transaction").build());
 try {
  transaction.commit();
  fail("Expecting a failure");
 } catch (DatastoreException expected) {
  assertEquals("ABORTED", expected.getReason());
 }
}

代码示例来源：origin: googleapis/google-cloud-java

@Test
public void testTransactionWithQuery() {
 Query<Entity> query =
   Query.newEntityQueryBuilder()
     .setKind(KIND2)
     .setFilter(PropertyFilter.hasAncestor(KEY2))
     .build();
 Transaction transaction = datastore.newTransaction();
 QueryResults<Entity> results = transaction.run(query);
 assertEquals(ENTITY2, results.next());
 assertFalse(results.hasNext());
 transaction.add(ENTITY3);
 transaction.commit();
 assertEquals(ENTITY3, datastore.get(KEY3));
 transaction = datastore.newTransaction();
 results = transaction.run(query);
 assertEquals(ENTITY2, results.next());
 transaction.delete(ENTITY3.getKey());
 // update entity2 during the transaction
 datastore.put(Entity.newBuilder(ENTITY2).clear().build());
 try {
  transaction.commit();
  fail("Expecting a failure");
 } catch (DatastoreException expected) {
  assertEquals("ABORTED", expected.getReason());
 }
}

代码示例来源：origin: googleapis/google-cloud-java

.setNamespace(NAMESPACE)
    .build();
Transaction transaction = DATASTORE.newTransaction();
QueryResults<Entity> results = transaction.run(query);
assertTrue(results.hasNext());
assertEquals(ENTITY3, DATASTORE.get(KEY3));
transaction = DATASTORE.newTransaction();
results = transaction.run(query);
assertTrue(results.hasNext());

代码示例来源：origin: GoogleCloudPlatform/java-docs-samples

/**
 * Marks a task entity as done.
 *
 * @param id The ID of the task entity as given by {@link Key#id()}
 * @return true if the task was found, false if not
 * @throws DatastoreException if the transaction fails
 */
boolean markDone(long id) {
 Transaction transaction = datastore.newTransaction();
 try {
  Entity task = transaction.get(keyFactory.newKey(id));
  if (task != null) {
   transaction.put(Entity.newBuilder(task).set("done", true).build());
  }
  transaction.commit();
  return task != null;
 } finally {
  if (transaction.isActive()) {
   transaction.rollback();
  }
 }
}
// [END datastore_update_entity]

代码示例来源：origin: spotify/styx

@Override
public Transaction newTransaction(TransactionOptions transactionOptions) {
 return InstrumentedTransaction.of(stats, delegate.newTransaction(transactionOptions));
}

代码示例来源：origin: spotify/styx

@Override
public Transaction newTransaction() {
 return InstrumentedTransaction.of(stats, delegate.newTransaction());
}

代码示例来源：origin: spotify/styx

/**
 * @see Datastore#newTransaction()
 * @throws DatastoreIOException if the underlying client throws {@link DatastoreException}
 */
CheckedDatastoreTransaction newTransaction() throws DatastoreIOException {
 try {
  return new CheckedDatastoreTransaction(this, datastore.newTransaction());
 } catch (DatastoreException e) {
  throw new DatastoreIOException(e);
 }
}

代码示例来源：origin: sai-pullabhotla/catatumbo

/**
 * Creates a new instance of <code>DatastoreTransaction</code>.
 * 
 * @param entityManager
 *          the entity manager that created this transaction.
 * @param transactionMode
 *          the transaction mode
 */
public DefaultDatastoreTransaction(DefaultEntityManager entityManager,
  TransactionMode transactionMode) {
 this.entityManager = entityManager;
 this.datastore = entityManager.getDatastore();
 this.nativeTransaction = datastore
   .newTransaction(transactionMode.getNativeTransactionOptions());
 this.reader = new DefaultDatastoreReader(this);
 this.writer = new TransactionalWriter(this);
}

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