com.aerospike.client.Txn Maven / Gradle / Ivy
/*
* Copyright 2012-2024 Aerospike, Inc.
*
* Portions may be licensed to Aerospike, Inc. under one or more contributor
* license agreements WHICH ARE COMPATIBLE WITH THE APACHE LICENSE, VERSION 2.0.
*
* Licensed under the Apache License, Version 2.0 (the "License"); you may not
* use this file except in compliance with the License. You may obtain a copy of
* the License at http://www.apache.org/licenses/LICENSE-2.0
*
* Unless required by applicable law or agreed to in writing, software
* distributed under the License is distributed on an "AS IS" BASIS, WITHOUT
* WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. See the
* License for the specific language governing permissions and limitations under
* the License.
*/
package com.aerospike.client;
import java.util.List;
import java.util.Map;
import java.util.Set;
import java.util.concurrent.ConcurrentHashMap;
import java.util.concurrent.atomic.AtomicLong;
/**
* Multi-record transaction (MRT). Each command in the MRT must use the same namespace.
*/
public final class Txn {
/**
* MRT state.
*/
public static enum State {
OPEN,
VERIFIED,
COMMITTED,
ABORTED;
}
private static AtomicLong randomState = new AtomicLong(System.nanoTime());
private final long id;
private final ConcurrentHashMap reads;
private final Set writes;
private Txn.State state;
private String namespace;
private int timeout;
private int deadline;
private boolean writeInDoubt;
private boolean inDoubt;
/**
* Create MRT, assign random transaction id and initialize reads/writes hashmaps with default
* capacities.
*
* The default client MRT timeout is zero. This means use the server configuration mrt-duration
* as the MRT timeout. The default mrt-duration is 10 seconds.
*/
public Txn() {
id = createId();
reads = new ConcurrentHashMap<>();
writes = ConcurrentHashMap.newKeySet();
state = Txn.State.OPEN;
}
/**
* Create MRT, assign random transaction id and initialize reads/writes hashmaps with given
* capacities.
*
* The default client MRT timeout is zero. This means use the server configuration mrt-duration
* as the MRT timeout. The default mrt-duration is 10 seconds.
*
* @param readsCapacity expected number of record reads in the MRT. Minimum value is 16.
* @param writesCapacity expected number of record writes in the MRT. Minimum value is 16.
*/
public Txn(int readsCapacity, int writesCapacity) {
if (readsCapacity < 16) {
readsCapacity = 16;
}
if (writesCapacity < 16) {
writesCapacity = 16;
}
id = createId();
reads = new ConcurrentHashMap<>(readsCapacity);
writes = ConcurrentHashMap.newKeySet(writesCapacity);
state = Txn.State.OPEN;
}
private static long createId() {
// xorshift64* doesn't generate zeroes.
long oldState;
long newState;
do {
oldState = randomState.get();
newState = oldState;
newState ^= newState >>> 12;
newState ^= newState << 25;
newState ^= newState >>> 27;
} while (!randomState.compareAndSet(oldState, newState));
return newState * 0x2545f4914f6cdd1dl;
}
/**
* Return MRT ID.
*/
public long getId() {
return id;
}
/**
* Set MRT timeout in seconds. The timer starts when the MRT monitor record is created.
* This occurs when the first command in the MRT is executed. If the timeout is reached before
* a commit or abort is called, the server will expire and rollback the MRT.
*
* If the MRT timeout is zero, the server configuration mrt-duration is used.
* The default mrt-duration is 10 seconds.
*/
public void setTimeout(int timeout) {
this.timeout = timeout;
}
/**
* Return MRT timeout in seconds.
*/
public int getTimeout() {
return timeout;
}
/**
* Verify current MRT state and namespace for a future read command.
*/
void prepareRead(String ns) {
verifyCommand();
setNamespace(ns);
}
/**
* Verify current MRT state and namespaces for a future batch read command.
*/
void prepareRead(Key[] keys) {
verifyCommand();
setNamespace(keys);
}
/**
* Verify current MRT state and namespaces for a future batch read command.
*/
void prepareRead(List records) {
verifyCommand();
setNamespace(records);
}
/**
* Verify that the MRT state allows future commands.
*/
public void verifyCommand() {
if (state != Txn.State.OPEN) {
throw new AerospikeException("Command not allowed in current MRT state: " + state);
}
}
/**
* Process the results of a record read. For internal use only.
*/
public void onRead(Key key, Long version) {
if (version != null) {
reads.put(key, version);
}
}
/**
* Get record version for a given key.
*/
public Long getReadVersion(Key key) {
return reads.get(key);
}
/**
* Get all read keys and their versions.
*/
public Set> getReads() {
return reads.entrySet();
}
/**
* Process the results of a record write. For internal use only.
*/
public void onWrite(Key key, Long version, int resultCode) {
if (version != null) {
reads.put(key, version);
}
else {
if (resultCode == ResultCode.OK) {
reads.remove(key);
writes.add(key);
}
}
}
/**
* Add key to write hash when write command is in doubt (usually caused by timeout).
*/
public void onWriteInDoubt(Key key) {
writeInDoubt = true;
reads.remove(key);
writes.add(key);
}
/**
* Get all write keys and their versions.
*/
public Set getWrites() {
return writes;
}
/**
* Set MRT namespace only if doesn't already exist.
* If namespace already exists, verify new namespace is the same.
*/
public void setNamespace(String ns) {
if (namespace == null) {
namespace = ns;
}
else if (! namespace.equals(ns)) {
throw new AerospikeException("Namespace must be the same for all commands in the MRT. orig: " +
namespace + " new: " + ns);
}
}
/**
* Set MRT namespaces for each key only if doesn't already exist.
* If namespace already exists, verify new namespace is the same.
*/
private void setNamespace(Key[] keys) {
for (Key key : keys) {
setNamespace(key.namespace);
}
}
/**
* Set MRT namespaces for each key only if doesn't already exist.
* If namespace already exists, verify new namespace is the same.
*/
private void setNamespace(List records) {
for (BatchRead br : records) {
setNamespace(br.key.namespace);
}
}
/**
* Return MRT namespace.
*/
public String getNamespace() {
return namespace;
}
/**
* Set MRT deadline. The deadline is a wall clock time calculated by the server from the
* MRT timeout that is sent by the client when creating the MRT monitor record. This deadline
* is used to avoid client/server clock skew issues. For internal use only.
*/
public void setDeadline(int deadline) {
this.deadline = deadline;
}
/**
* Get MRT deadline. For internal use only.
*/
public int getDeadline() {
return deadline;
}
/**
* Return if the MRT monitor record should be closed/deleted. For internal use only.
*/
public boolean closeMonitor() {
return deadline != 0 && !writeInDoubt;
}
/**
* Does MRT monitor record exist.
*/
public boolean monitorExists() {
return deadline != 0;
}
/**
* Set MRT state. For internal use only.
*/
public void setState(Txn.State state) {
this.state = state;
}
/**
* Return MRT state.
*/
public Txn.State getState() {
return state;
}
/**
* Set MRT inDoubt flag. For internal use only.
*/
public void setInDoubt(boolean inDoubt) {
this.inDoubt = inDoubt;
}
/**
* Return if MRT is inDoubt.
*/
public boolean getInDoubt() {
return inDoubt;
}
/**
* Clear MRT. Remove all tracked keys.
*/
public void clear() {
namespace = null;
deadline = 0;
reads.clear();
writes.clear();
}
}