import org.apache.zookeeper.proto.SyncRequest; //导入依赖的package包/类
/**
 * Asynchronous sync. Flushes channel between process and leader.
 * @param path
 * @param cb a handler for the callback
 * @param ctx context to be provided to the callback
 * @throws IllegalArgumentException if an invalid path is specified
 */
public void sync(final String path, VoidCallback cb, Object ctx){
    final String clientPath = path;
    PathUtils.validatePath(clientPath);

    final String serverPath = prependChroot(clientPath);

    RequestHeader h = new RequestHeader();
    h.setType(ZooDefs.OpCode.sync);
    SyncRequest request = new SyncRequest();
    SyncResponse response = new SyncResponse();
    request.setPath(serverPath);
    cnxn.queuePacket(h, new ReplyHeader(), request, response, cb,
            clientPath, serverPath, ctx, null);
}
 

import org.apache.zookeeper.proto.SyncRequest; //导入依赖的package包/类
private EventType checkType(Record response) {

        if (response == null) {
            return EventType.other;
        } else if (response instanceof ConnectRequest) {
            return EventType.write;
        } else if (response instanceof CreateRequest) {
            return EventType.write;
        } else if (response instanceof DeleteRequest) {
            return EventType.write;
        } else if (response instanceof SetDataRequest) {
            return EventType.write;
        } else if (response instanceof SetACLRequest) {
            return EventType.write;
        } else if (response instanceof SetMaxChildrenRequest) {
            return EventType.write;
        } else if (response instanceof SetSASLRequest) {
            return EventType.write;
        } else if (response instanceof SetWatches) {
            return EventType.write;
        } else if (response instanceof SyncRequest) {
            return EventType.write;
        } else if (response instanceof ExistsRequest) {
            return EventType.read;
        } else if (response instanceof GetDataRequest) {
            return EventType.read;
        } else if (response instanceof GetMaxChildrenRequest) {
            return EventType.read;
        } else if (response instanceof GetACLRequest) {
            return EventType.read;
        } else if (response instanceof GetChildrenRequest) {
            return EventType.read;
        } else if (response instanceof GetChildren2Request) {
            return EventType.read;
        } else if (response instanceof GetSASLRequest) {
            return EventType.read;
        } else {
            return EventType.other;
        }
    }
 

import org.apache.zookeeper.proto.SyncRequest; //导入依赖的package包/类
@Test
public void raceTest() 
throws Exception {

   ByteArrayOutputStream boas = new ByteArrayOutputStream();
   BinaryOutputArchive boa = BinaryOutputArchive.getArchive(boas);
   GetDataRequest getReq = new GetDataRequest("/testrace", false);
   getReq.serialize(boa, "request");
   ByteBuffer bb = ByteBuffer.wrap(boas.toByteArray());
   Request readReq = new Request(null, 0x0, 0, OpCode.getData,
           bb, new ArrayList<Id>());

   boas.reset();
   SyncRequest syncReq = new SyncRequest("/testrace");
   syncReq.serialize(boa, "request");
   bb = ByteBuffer.wrap(boas.toByteArray());
   Request writeReq = new Request(null, 0x0, 0, OpCode.sync,
                             bb, new ArrayList<Id>());

   processor.addToCommittedRequests(writeReq);
   processor.addToQueuedRequests(readReq);
   processor.addToQueuedRequests(writeReq);

   processor.testStart();
   processor.testProcessCommitted();
   Assert.assertFalse("Next request processor executed", executedFlag);
}
 

import org.apache.zookeeper.proto.SyncRequest; //导入依赖的package包/类
public ISyncRequest() {
    this(new SyncRequest());
}