import com.google.ipc.invalidation.common.ObjectIdDigestUtils; //导入依赖的package包/类
@Override
public Collection<ObjectIdP> add(Collection<ObjectIdP> oids) {
  Collection<ObjectIdP> addedOids = new ArrayList<ObjectIdP>();
  for (ObjectIdP oid : oids) {
    if (registrations.put(ObjectIdDigestUtils.getDigest(oid.getSource(),
        oid.getName().getByteArray(), digestFunction), oid) == null) {
      // There was no previous value, so this is a new item.
      addedOids.add(oid);
    }
  }
  if (!addedOids.isEmpty()) {
    // Only recompute the digest if we made changes.
    recomputeDigest();
  }
  return addedOids;
}
 

import com.google.ipc.invalidation.common.ObjectIdDigestUtils; //导入依赖的package包/类
@Override
public boolean remove(ObjectIdP oid) {
  if (registrations.remove(ObjectIdDigestUtils.getDigest(oid.getSource(),
      oid.getName().getByteArray(), digestFunction)) != null) {
    recomputeDigest();
    return true;
  }
  return false;
}
 

import com.google.ipc.invalidation.common.ObjectIdDigestUtils; //导入依赖的package包/类
@Override

public RegistrationManagerState getRegistrationManagerStateCopyForTest() {
  Preconditions.checkState(resources.getInternalScheduler().isRunningOnThread());
  return registrationManager.getRegistrationManagerStateCopyForTest(
      new ObjectIdDigestUtils.Sha1DigestFunction());
}
 

import com.google.ipc.invalidation.common.ObjectIdDigestUtils; //导入依赖的package包/类
@Override
public boolean add(ObjectIdP oid) {
  if (registrations.put(ObjectIdDigestUtils.getDigest(oid, digestFunction), oid) == null) {
    recomputeDigest();
    return true;
  }
  return false;
}
 

import com.google.ipc.invalidation.common.ObjectIdDigestUtils; //导入依赖的package包/类
@Override
public boolean remove(ObjectIdP oid) {
  if (registrations.remove(ObjectIdDigestUtils.getDigest(oid, digestFunction)) != null) {
    recomputeDigest();
    return true;
  }
  return false;
}
 

import com.google.ipc.invalidation.common.ObjectIdDigestUtils; //导入依赖的package包/类
@Override
public boolean contains(ObjectIdP oid) {
  return registrations.containsKey(ObjectIdDigestUtils.getDigest(oid.getSource(),
      oid.getName().getByteArray(), digestFunction));
}
 

import com.google.ipc.invalidation.common.ObjectIdDigestUtils; //导入依赖的package包/类
/** Recomputes the digests over all objects and sets {@code this.digest}. */
private void recomputeDigest() {
  this.digest = ObjectIdDigestUtils.getDigest(registrations.keySet(), digestFunction);
}
 

import com.google.ipc.invalidation.common.ObjectIdDigestUtils; //导入依赖的package包/类
@Override
public boolean contains(ObjectIdP oid) {
  return registrations.containsKey(ObjectIdDigestUtils.getDigest(oid, digestFunction));
}