geode-core/src/main/java/org/apache/geode/internal/cache/persistence/PersistentMemberPattern.java

/*
 * Licensed to the Apache Software Foundation (ASF) under one or more contributor license
 * agreements. See the NOTICE file distributed with this work for additional information regarding
 * copyright ownership. The ASF licenses this file to You under the Apache License, Version 2.0 (the
 * "License"); you may not use this file except in compliance with the License. You may obtain a
 * copy of the License at
 *
 * http://www.apache.org/licenses/LICENSE-2.0
 *
 * Unless required by applicable law or agreed to in writing, software distributed under the License
 * is distributed on an "AS IS" BASIS, WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express
 * or implied. See the License for the specific language governing permissions and limitations under
 * the License.
 */
package org.apache.geode.internal.cache.persistence;

import java.io.DataInput;
import java.io.DataOutput;
import java.io.IOException;
import java.net.InetAddress;
import java.util.UUID;

import org.apache.geode.DataSerializer;
import org.apache.geode.cache.persistence.PersistentID;
import org.apache.geode.internal.net.SocketCreator;

/**
 * Implementation of the public PersistentID. It holds the region, host, directory, and timestamp.
 *
 * This class also is also used to describe members that the user has revoked. Any fields that are
 * null will be considered a wildcard matching any members.
 *
 * @since GemFire prPersistSprint1
 */
public class PersistentMemberPattern implements PersistentID, Comparable<PersistentMemberPattern> {

  private InetAddress host;
  private String directory;
  private UUID diskStoreID;
  private long revokedTime;

  public PersistentMemberPattern(PersistentMemberID id) {
    this(id.getHost(), id.getDirectory(), id.getDiskStoreId().toUUID(), 0);
  }

  public PersistentMemberPattern(InetAddress host, String directory) {
    this(host, directory, null, 0);
  }

  public PersistentMemberPattern(InetAddress host, String directory, long revokedTime) {
    this(host, directory, null, revokedTime);
  }

  public PersistentMemberPattern(UUID id) {
    this(null, null, id, 0);
  }

  public PersistentMemberPattern(InetAddress host, String directory, UUID diskStoreID,
      long revokedTime) {
    this.host = host;
    this.directory = directory;
    this.revokedTime = revokedTime;
    this.diskStoreID = diskStoreID;
  }

  public PersistentMemberPattern() {
    // Used for deserialization only
  }

  public boolean matches(PersistentMemberID id) {
    if (id == null) {
      return false;
    }
    boolean matches = true;
    matches &= host == null || host.equals(id.getHost());
    matches &= directory == null || directory.equals(id.getDirectory());
    matches &= diskStoreID == null
        || id.getDiskStoreId().getMostSignificantBits() == diskStoreID.getMostSignificantBits()
            && id.getDiskStoreId().getLeastSignificantBits() == diskStoreID
                .getLeastSignificantBits();

    // Safety measure. Id's which are generated after this pattern was revoked
    // should not be revoked. For example, if someone loses the disk for server A
    // They may revoke the pattern host==A. But A will start and generate a new ID
    // if they then close the region everywhere and then reopen it, we don't want
    // the new pattern to be revoked.
    if (diskStoreID == null) {
      matches &= revokedTime > id.getTimeStamp();
    }
    return matches;
  }

  @Override
  public String toString() {
    StringBuilder result = new StringBuilder();
    result.append(diskStoreID);
    if (host != null) {
      result.append(" [");
      result.append(SocketCreator.getHostName(host));
      result.append(":");
      result.append(directory);
      result.append(",revoked@").append(revokedTime);
      result.append("]");
    }

    return result.toString();
  }

  @Override
  public int hashCode() {
    final int prime = 31;
    int result = 1;
    result = prime * result + ((directory == null) ? 0 : directory.hashCode());
    result = prime * result + ((diskStoreID == null) ? 0 : diskStoreID.hashCode());
    result = prime * result + ((host == null) ? 0 : host.hashCode());
    result = prime * result + (int) (revokedTime ^ (revokedTime >>> 32));
    return result;
  }

  @Override
  public boolean equals(Object obj) {
    if (this == obj)
      return true;
    if (obj == null)
      return false;
    if (getClass() != obj.getClass())
      return false;
    PersistentMemberPattern other = (PersistentMemberPattern) obj;
    if (directory == null) {
      if (other.directory != null)
        return false;
    } else if (!directory.equals(other.directory))
      return false;
    if (diskStoreID == null) {
      if (other.diskStoreID != null)
        return false;
    } else if (!diskStoreID.equals(other.diskStoreID))
      return false;
    if (host == null) {
      if (other.host != null)
        return false;
    } else if (!host.equals(other.host))
      return false;
    if (revokedTime != other.revokedTime)
      return false;
    return true;
  }

  @Override
  public InetAddress getHost() {
    return host;
  }

  @Override
  public String getDirectory() {
    return directory;
  }

  @Override
  public UUID getUUID() {
    return diskStoreID;
  }

  @Override
  public void fromData(DataInput in) throws IOException, ClassNotFoundException {
    boolean hasHost = in.readBoolean();
    if (hasHost) {
      host = DataSerializer.readInetAddress(in);
    }
    boolean hasDirectory = in.readBoolean();
    if (hasDirectory) {
      directory = DataSerializer.readString(in);
    }
    diskStoreID = DataSerializer.readObject(in);
    revokedTime = in.readLong();
  }

  @Override
  public void toData(DataOutput out) throws IOException {
    out.writeBoolean(host != null);
    if (host != null) {
      DataSerializer.writeInetAddress(host, out);
    }
    out.writeBoolean(directory != null);
    if (directory != null) {
      DataSerializer.writeString(directory, out);
    }

    DataSerializer.writeObject(diskStoreID, out);
    out.writeLong(revokedTime);
  }

  @Override
  public int compareTo(PersistentMemberPattern o) {
    int result = compare(diskStoreID, o.diskStoreID);
    if (result != 0) {
      return result;
    }
    result = compare(host == null ? null : host.getCanonicalHostName(),
        o.host == null ? null : o.host.getCanonicalHostName());
    if (result != 0) {
      return result;
    }
    result = compare(directory, o.directory);
    if (result != 0) {
      return result;
    }

    result = Long.signum(revokedTime - o.revokedTime);

    return result;
  }

  private <X> int compare(Comparable<X> a, X b) {
    if (a == null) {
      if (b == null) {
        return 0;
      } else {
        return -1;
      }
    }
    if (b == null) {
      return 1;
    }

    return a.compareTo(b);
  }
}