package org.multiverse.stms.gamma.integration.locks;
import org.junit.Before;
import org.junit.Test;
import org.multiverse.api.LockMode;
import org.multiverse.api.exceptions.ReadWriteConflict;
import org.multiverse.stms.gamma.GammaStm;
import org.multiverse.stms.gamma.transactionalobjects.GammaTxnLong;
import org.multiverse.stms.gamma.transactions.GammaTxn;
import static org.junit.Assert.assertEquals;
import static org.junit.Assert.fail;
import static org.multiverse.TestUtils.*;
import static org.multiverse.api.GlobalStmInstance.getGlobalStmInstance;
import static org.multiverse.api.TxnThreadLocal.clearThreadLocalTxn;
import static org.multiverse.stms.gamma.GammaTestUtils.*;
public class ExclusiveLockTest {
private GammaStm stm;
@Before
public void setUp() {
stm = (GammaStm) getGlobalStmInstance();
clearThreadLocalTxn();
}
@Test
public void whenUnlocked() {
GammaTxnLong ref = new GammaTxnLong(stm, 10);
GammaTxn tx = stm.newDefaultTxn();
ref.getLock().acquire(tx, LockMode.Exclusive);
assertIsActive(tx);
assertRefHasExclusiveLock(ref, tx);
}
@Test
public void whenReadLockAlreadyAcquiredByOther_thenExclusiveLockNotPossible() {
GammaTxnLong ref = new GammaTxnLong(stm);
GammaTxn otherTx = stm.newDefaultTxn();
ref.getLock().acquire(otherTx, LockMode.Read);
GammaTxn tx = stm.newDefaultTxn();
try {
ref.getLock().acquire(tx, LockMode.Exclusive);
fail();
} catch (ReadWriteConflict expected) {
}
assertIsAborted(tx);
assertRefHasReadLock(ref, otherTx);
}
@Test
public void whenExclusiveLockAlreadyAcquiredByOther_thenExclusiveLockNotPossible() {
GammaTxnLong ref = new GammaTxnLong(stm);
GammaTxn otherTx = stm.newDefaultTxn();
ref.getLock().acquire(otherTx, LockMode.Exclusive);
GammaTxn tx = stm.newDefaultTxn();
try {
ref.getLock().acquire(tx, LockMode.Exclusive);
fail();
} catch (ReadWriteConflict expected) {
}
assertIsAborted(tx);
assertRefHasExclusiveLock(ref, otherTx);
}
@Test
public void whenWriteLockAlreadyAcquiredByOther_thenExclusiveLockNotPossible() {
GammaTxnLong ref = new GammaTxnLong(stm);
GammaTxn otherTx = stm.newDefaultTxn();
ref.getLock().acquire(otherTx, LockMode.Write);
GammaTxn tx = stm.newDefaultTxn();
try {
ref.getLock().acquire(tx, LockMode.Exclusive);
fail();
} catch (ReadWriteConflict expected) {
}
assertIsAborted(tx);
assertRefHasWriteLock(ref, otherTx);
}
@Test
public void whenExclusiveLockAcquiredByOther_thenReadNotPossible() {
GammaTxnLong ref = new GammaTxnLong(stm);
GammaTxn tx = stm.newDefaultTxn();
ref.getLock().acquire(tx, LockMode.Exclusive);
GammaTxn otherTx = stm.newDefaultTxn();
try {
ref.get(otherTx);
fail();
} catch (ReadWriteConflict expected) {
}
}
@Test
public void whenPreviouslyReadByOtherThread_thenNoProblems() {
GammaTxnLong ref = new GammaTxnLong(stm, 10);
GammaTxn otherTx = stm.newDefaultTxn();
ref.get(otherTx);
GammaTxn tx = stm.newDefaultTxn();
ref.getLock().acquire(tx, LockMode.Exclusive);
long result = ref.get(otherTx);
assertEquals(10, result);
}
@Test
public void whenPreviouslyReadByOtherThread_thenWriteSuccessButExclusiveFails() {
GammaTxnLong ref = new GammaTxnLong(stm, 10);
GammaTxn tx = stm.newDefaultTxn();
ref.get(tx);
GammaTxn otherTx = stm.newDefaultTxn();
ref.getLock().acquire(otherTx, LockMode.Exclusive);
ref.set(tx, 100);
try {
tx.commit();
fail();
} catch (ReadWriteConflict expected) {
}
assertIsAborted(tx);
assertRefHasExclusiveLock(ref, otherTx);
}
@Test
public void whenExclusiveLockAcquiredByOther_thenWriteNotAllowed() {
GammaTxnLong ref = new GammaTxnLong(stm, 5);
GammaTxn otherTx = stm.newDefaultTxn();
ref.getLock().acquire(otherTx, LockMode.Exclusive);
GammaTxn tx = stm.newDefaultTxn();
try {
ref.set(tx, 100);
fail();
} catch (ReadWriteConflict expected) {
}
assertIsAborted(tx);
assertRefHasExclusiveLock(ref, otherTx);
}
@Test
public void writeLockIsUpgradableToExclusiveLock() {
GammaTxnLong ref = new GammaTxnLong(stm, 5);
GammaTxn tx = stm.newDefaultTxn();
ref.getLock().acquire(tx, LockMode.Write);
ref.getLock().acquire(tx, LockMode.Exclusive);
assertIsActive(tx);
assertRefHasExclusiveLock(ref, tx);
}
@Test
public void whenReadLockAcquired_thenUpgradableToExclusiveLock() {
GammaTxnLong ref = new GammaTxnLong(stm, 5);
GammaTxn tx = stm.newDefaultTxn();
ref.getLock().acquire(tx, LockMode.Read);
ref.getLock().acquire(tx, LockMode.Exclusive);
assertIsActive(tx);
assertRefHasExclusiveLock(ref, tx);
}
@Test
public void whenReadLockAlsoAcquiredByOther_thenNotUpgradableToExclusiveLock() {
GammaTxnLong ref = new GammaTxnLong(stm, 5);
GammaTxn otherTx = stm.newDefaultTxn();
ref.getLock().acquire(otherTx, LockMode.Read);
GammaTxn tx = stm.newDefaultTxn();
ref.getLock().acquire(tx, LockMode.Read);
try {
ref.getLock().acquire(tx, LockMode.Exclusive);
fail();
} catch (ReadWriteConflict expected) {
}
assertIsAborted(tx);
assertRefHasReadLock(ref, otherTx);
assertReadLockCount(ref, 1);
}
@Test
public void whenTransactionCommits_thenExclusiveLockReleased() {
GammaTxnLong ref = new GammaTxnLong(stm, 5);
GammaTxn tx = stm.newDefaultTxn();
ref.getLock().acquire(tx, LockMode.Exclusive);
tx.commit();
assertIsCommitted(tx);
assertRefHasNoLocks(ref);
}
@Test
public void whenTransactionIsPrepared_thenExclusiveLockRemains() {
GammaTxnLong ref = new GammaTxnLong(stm, 5);
GammaTxn tx = stm.newDefaultTxn();
ref.getLock().acquire(tx, LockMode.Exclusive);
tx.prepare();
assertIsPrepared(tx);
assertRefHasExclusiveLock(ref, tx);
}
@Test
public void whenTransactionAborts_thenExclusiveLockIsReleased() {
GammaTxnLong ref = new GammaTxnLong(stm, 5);
GammaTxn tx = stm.newDefaultTxn();
ref.getLock().acquire(tx, LockMode.Exclusive);
tx.abort();
assertIsAborted(tx);
assertRefHasNoLocks(ref);
}
@Test
public void whenExclusiveLockAlreadyIsAcquired_thenReentrantExclusiveLockIsSuccess() {
GammaTxnLong ref = new GammaTxnLong(stm, 5);
GammaTxn tx = stm.newDefaultTxn();
ref.getLock().acquire(tx, LockMode.Exclusive);
ref.getLock().acquire(tx, LockMode.Exclusive);
assertIsActive(tx);
assertRefHasExclusiveLock(ref, tx);
}
@Test
public void whenReadConflict_thenExclusiveLockFails() {
GammaTxnLong ref = new GammaTxnLong(stm, 5);
GammaTxn tx = stm.newDefaultTxn();
ref.get(tx);
ref.atomicIncrementAndGet(1);
try {
ref.getLock().acquire(tx, LockMode.Exclusive);
fail();
} catch (ReadWriteConflict expected) {
}
assertRefHasNoLocks(ref);
assertIsAborted(tx);
}
}