com.github.ltsopensource.kv.index.AbstractIndexSnapshot Maven / Gradle / Ivy
package com.github.ltsopensource.kv.index;
import com.github.ltsopensource.core.factory.NamedThreadFactory;
import com.github.ltsopensource.kv.DB;
import com.github.ltsopensource.kv.StoreConfig;
import com.github.ltsopensource.kv.serializer.StoreSerializer;
import com.github.ltsopensource.core.logger.Logger;
import java.io.IOException;
import java.util.concurrent.Executors;
import java.util.concurrent.ScheduledExecutorService;
import java.util.concurrent.ScheduledFuture;
import java.util.concurrent.TimeUnit;
/**
* @author Robert HG ([email protected]) on 12/16/15.
*/
public abstract class AbstractIndexSnapshot implements IndexSnapshot {
protected static final Logger LOGGER = DB.LOGGER;
private ScheduledExecutorService executorService;
private ScheduledFuture future;
protected Index index;
protected StoreSerializer serializer;
protected StoreConfig storeConfig;
public AbstractIndexSnapshot(Index index, StoreConfig storeConfig, StoreSerializer serializer) {
this.index = index;
this.storeConfig = storeConfig;
this.serializer = serializer;
this.executorService = Executors.newSingleThreadScheduledExecutor(new NamedThreadFactory("ltsdb-index-snapshot-service", true));
}
public void init() throws IOException {
// 1. load from disk
loadFromDisk();
// 2. replay txLog
replayTxLog();
future = this.executorService.scheduleWithFixedDelay(new Runnable() {
@Override
public void run() {
try {
snapshot();
} catch (Throwable t) {
LOGGER.error("MemIndexSnapshot snapshot error:" + t.getMessage(), t);
}
}
}, storeConfig.getIndexSnapshotInterval(),
storeConfig.getIndexSnapshotInterval(), TimeUnit.MILLISECONDS);
}
/**
* 从磁盘中加载snapshot到内存中
*/
protected abstract void loadFromDisk() throws IOException;
/**
* 重放没有持久化的事务日志
*/
protected abstract void replayTxLog();
}