@Override public Void run(TransactionContext transaction) throws Exception { String column = "FirstName"; Struct row = transaction.readRow("Singers", Key.of(singerId), Collections.singleton(column)); String name = row.getString(column); transaction.buffer( Mutation.newUpdateBuilder("Singers").set(column).to(name.toUpperCase()).build()); return null; } });
@Override public Void run(TransactionContext transaction) { long rowCount = transaction.executeUpdate(Statement.of("UPDATE T SET v = v * 2 WHERE k = 'boo2';")); assertThat(rowCount).isEqualTo(1); assertThat(transaction.readRow("T", Key.of("boo2"), Arrays.asList("v")).getLong(0)) .isEqualTo(2 * 2); return null; } };
/** Example of using {@link TransactionManager}. */ // [TARGET transactionManager()] // [VARIABLE my_singer_id] public void transactionManager(final long singerId) throws InterruptedException { // [START transactionManager] try (TransactionManager manager = dbClient.transactionManager()) { TransactionContext txn = manager.begin(); while (true) { String column = "FirstName"; Struct row = txn.readRow("Singers", Key.of(singerId), Collections.singleton(column)); String name = row.getString(column); txn.buffer(Mutation.newUpdateBuilder("Singers").set(column).to(name.toUpperCase()).build()); try { manager.commit(); break; } catch (AbortedException e) { Thread.sleep(e.getRetryDelayInMillis() / 1000); txn = manager.resetForRetry(); } } } // [END transactionManager] } }
TransactionManager manager1 = client.transactionManager(); TransactionContext txn1 = manager1.begin(); txn1.readRow("T", Key.of("Key3"), Arrays.asList("K", "BoolValue")); TransactionManager manager2 = client.transactionManager(); TransactionContext txn2 = manager2.begin(); txn2.readRow("T", Key.of("Key3"), Arrays.asList("K", "BoolValue"));