Java ColumnFamilyStore.snapshot方法代码示例

import org.apache.cassandra.db.ColumnFamilyStore; //导入方法依赖的package包/类
/**
 * Takes the snapshot of a specific column family. A snapshot name must be specified.
 *
 * @param keyspaceName the keyspace which holds the specified column family
 * @param columnFamilyName the column family to snapshot
 * @param tag the tag given to the snapshot; may not be null or empty
 */
public void takeColumnFamilySnapshot(String keyspaceName, String columnFamilyName, String tag) throws IOException
{
    if (keyspaceName == null)
        throw new IOException("You must supply a keyspace name");
    if (operationMode.equals(Mode.JOINING))
        throw new IOException("Cannot snapshot until bootstrap completes");

    if (columnFamilyName == null)
        throw new IOException("You must supply a column family name");
    if (columnFamilyName.contains("."))
        throw new IllegalArgumentException("Cannot take a snapshot of a secondary index by itself. Run snapshot on the column family that owns the index.");

    if (tag == null || tag.equals(""))
        throw new IOException("You must supply a snapshot name.");

    Keyspace keyspace = getValidKeyspace(keyspaceName);
    ColumnFamilyStore columnFamilyStore = keyspace.getColumnFamilyStore(columnFamilyName);
    if (columnFamilyStore.snapshotExists(tag))
        throw new IOException("Snapshot " + tag + " already exists.");

    columnFamilyStore.snapshot(tag);
}
 

import org.apache.cassandra.db.ColumnFamilyStore; //导入方法依赖的package包/类
public void dropKeyspace(String ksName)
{
    KeyspaceMetadata ksm = Schema.instance.getKSMetaData(ksName);
    String snapshotName = Keyspace.getTimestampedSnapshotName(ksName);

    CompactionManager.instance.interruptCompactionFor(ksm.tablesAndViews(), true);

    Keyspace keyspace = Keyspace.open(ksm.name);

    // remove all cfs from the keyspace instance.
    List<UUID> droppedCfs = new ArrayList<>();
    for (CFMetaData cfm : ksm.tablesAndViews())
    {
        ColumnFamilyStore cfs = keyspace.getColumnFamilyStore(cfm.cfName);

        unload(cfm);

        if (DatabaseDescriptor.isAutoSnapshot())
            cfs.snapshot(snapshotName);
        Keyspace.open(ksm.name).dropCf(cfm.cfId);

        droppedCfs.add(cfm.cfId);
    }

    // remove the keyspace from the static instances.
    Keyspace.clear(ksm.name);
    clearKeyspaceMetadata(ksm);

    Keyspace.writeOrder.awaitNewBarrier();

    // force a new segment in the CL
    CommitLog.instance.forceRecycleAllSegments(droppedCfs);

    MigrationManager.instance.notifyDropKeyspace(ksm);
}
 

import org.apache.cassandra.db.ColumnFamilyStore; //导入方法依赖的package包/类
@Test
public void testCompactionHook() throws Exception
{
    Assume.assumeTrue(FBUtilities.isWindows());

    Keyspace keyspace = Keyspace.open(KEYSPACE1);
    ColumnFamilyStore store = keyspace.getColumnFamilyStore(CF_STANDARD1);
    store.clearUnsafe();

    populate(10000);
    store.snapshot("snapshot1");

    // Confirm snapshot deletion fails. Sleep for a bit just to make sure the SnapshotDeletingTask has
    // time to run and fail.
    Thread.sleep(500);
    store.clearSnapshot("snapshot1");
    assertEquals(1, SnapshotDeletingTask.pendingDeletionCount());

    // Compact the cf and confirm that the executor's after hook calls rescheduleDeletion
    populate(20000);
    store.forceBlockingFlush();
    store.forceMajorCompaction();

    long start = System.currentTimeMillis();
    while (System.currentTimeMillis() - start < 1000 && SnapshotDeletingTask.pendingDeletionCount() > 0)
    {
        Thread.yield();
    }

    assertEquals(0, SnapshotDeletingTask.pendingDeletionCount());
}