@Test
  public void testStateJumpToLeft() throws UnknownHostException {
    StorageService ss = StorageService.instance;
    TokenMetadata tmd = ss.getTokenMetadata();
    tmd.clearUnsafe();
    IPartitioner partitioner = RandomPartitioner.instance;
    VersionedValue.VersionedValueFactory valueFactory =
        new VersionedValue.VersionedValueFactory(partitioner);

    ArrayList<Token> endpointTokens = new ArrayList<Token>();
    ArrayList<Token> keyTokens = new ArrayList<Token>();
    List<InetAddress> hosts = new ArrayList<InetAddress>();
    List<UUID> hostIds = new ArrayList<UUID>();

    // create a ring of 6 nodes
    Util.createInitialRing(ss, partitioner, endpointTokens, keyTokens, hosts, hostIds, 7);

    // node hosts.get(2) goes jumps to left
    ss.onChange(
        hosts.get(2),
        ApplicationState.STATUS,
        valueFactory.left(
            Collections.singleton(endpointTokens.get(2)), Gossiper.computeExpireTime()));

    assertFalse(tmd.isMember(hosts.get(2)));

    // node hosts.get(4) goes to bootstrap
    Gossiper.instance.injectApplicationState(
        hosts.get(3),
        ApplicationState.TOKENS,
        valueFactory.tokens(Collections.singleton(keyTokens.get(1))));
    ss.onChange(
        hosts.get(3),
        ApplicationState.STATUS,
        valueFactory.bootstrapping(Collections.<Token>singleton(keyTokens.get(1))));

    assertFalse(tmd.isMember(hosts.get(3)));
    assertEquals(1, tmd.getBootstrapTokens().size());
    assertEquals(hosts.get(3), tmd.getBootstrapTokens().get(keyTokens.get(1)));

    // and then directly to 'left'
    Gossiper.instance.injectApplicationState(
        hosts.get(2),
        ApplicationState.TOKENS,
        valueFactory.tokens(Collections.singleton(keyTokens.get(1))));
    ss.onChange(
        hosts.get(2),
        ApplicationState.STATUS,
        valueFactory.left(Collections.singleton(keyTokens.get(1)), Gossiper.computeExpireTime()));

    assertTrue(tmd.getBootstrapTokens().size() == 0);
    assertFalse(tmd.isMember(hosts.get(2)));
    assertFalse(tmd.isLeaving(hosts.get(2)));
  }
  @Test
  public void testStateJumpToNormal() throws UnknownHostException {
    StorageService ss = StorageService.instance;
    TokenMetadata tmd = ss.getTokenMetadata();
    tmd.clearUnsafe();
    IPartitioner partitioner = RandomPartitioner.instance;
    VersionedValue.VersionedValueFactory valueFactory =
        new VersionedValue.VersionedValueFactory(partitioner);

    ArrayList<Token> endpointTokens = new ArrayList<Token>();
    ArrayList<Token> keyTokens = new ArrayList<Token>();
    List<InetAddress> hosts = new ArrayList<InetAddress>();
    List<UUID> hostIds = new ArrayList<UUID>();

    // create a ring or 5 nodes
    Util.createInitialRing(ss, partitioner, endpointTokens, keyTokens, hosts, hostIds, 6);

    // node 2 leaves
    ss.onChange(
        hosts.get(2),
        ApplicationState.STATUS,
        valueFactory.leaving(Collections.singleton(endpointTokens.get(2))));

    assertTrue(tmd.isLeaving(hosts.get(2)));
    assertEquals(endpointTokens.get(2), tmd.getToken(hosts.get(2)));

    // back to normal
    Gossiper.instance.injectApplicationState(
        hosts.get(2),
        ApplicationState.TOKENS,
        valueFactory.tokens(Collections.singleton(keyTokens.get(2))));
    ss.onChange(
        hosts.get(2),
        ApplicationState.STATUS,
        valueFactory.normal(Collections.singleton(keyTokens.get(2))));

    assertTrue(tmd.getLeavingEndpoints().isEmpty());
    assertEquals(keyTokens.get(2), tmd.getToken(hosts.get(2)));

    // node 3 goes through leave and left and then jumps to normal at its new token
    ss.onChange(
        hosts.get(2),
        ApplicationState.STATUS,
        valueFactory.leaving(Collections.singleton(keyTokens.get(2))));
    ss.onChange(
        hosts.get(2),
        ApplicationState.STATUS,
        valueFactory.left(Collections.singleton(keyTokens.get(2)), Gossiper.computeExpireTime()));
    Gossiper.instance.injectApplicationState(
        hosts.get(2),
        ApplicationState.TOKENS,
        valueFactory.tokens(Collections.singleton(keyTokens.get(4))));
    ss.onChange(
        hosts.get(2),
        ApplicationState.STATUS,
        valueFactory.normal(Collections.singleton(keyTokens.get(4))));

    assertTrue(tmd.getBootstrapTokens().isEmpty());
    assertTrue(tmd.getLeavingEndpoints().isEmpty());
    assertEquals(keyTokens.get(4), tmd.getToken(hosts.get(2)));
  }
  @Test
  public void testStateJumpToLeaving() throws UnknownHostException {
    StorageService ss = StorageService.instance;
    TokenMetadata tmd = ss.getTokenMetadata();
    tmd.clearUnsafe();
    IPartitioner partitioner = RandomPartitioner.instance;
    VersionedValue.VersionedValueFactory valueFactory =
        new VersionedValue.VersionedValueFactory(partitioner);

    ArrayList<Token> endpointTokens = new ArrayList<Token>();
    ArrayList<Token> keyTokens = new ArrayList<Token>();
    List<InetAddress> hosts = new ArrayList<InetAddress>();
    List<UUID> hostIds = new ArrayList<UUID>();

    // create a ring or 5 nodes
    Util.createInitialRing(ss, partitioner, endpointTokens, keyTokens, hosts, hostIds, 6);

    // node 2 leaves with _different_ token
    Gossiper.instance.injectApplicationState(
        hosts.get(2),
        ApplicationState.TOKENS,
        valueFactory.tokens(Collections.singleton(keyTokens.get(0))));
    ss.onChange(
        hosts.get(2),
        ApplicationState.STATUS,
        valueFactory.leaving(Collections.singleton(keyTokens.get(0))));

    assertEquals(keyTokens.get(0), tmd.getToken(hosts.get(2)));
    assertTrue(tmd.isLeaving(hosts.get(2)));
    assertNull(tmd.getEndpoint(endpointTokens.get(2)));

    // go to boostrap
    Gossiper.instance.injectApplicationState(
        hosts.get(2),
        ApplicationState.TOKENS,
        valueFactory.tokens(Collections.singleton(keyTokens.get(1))));
    ss.onChange(
        hosts.get(2),
        ApplicationState.STATUS,
        valueFactory.bootstrapping(Collections.<Token>singleton(keyTokens.get(1))));

    assertFalse(tmd.isLeaving(hosts.get(2)));
    assertEquals(1, tmd.getBootstrapTokens().size());
    assertEquals(hosts.get(2), tmd.getBootstrapTokens().get(keyTokens.get(1)));

    // jump to leaving again
    ss.onChange(
        hosts.get(2),
        ApplicationState.STATUS,
        valueFactory.leaving(Collections.singleton(keyTokens.get(1))));

    assertEquals(hosts.get(2), tmd.getEndpoint(keyTokens.get(1)));
    assertTrue(tmd.isLeaving(hosts.get(2)));
    assertTrue(tmd.getBootstrapTokens().isEmpty());

    // go to state left
    ss.onChange(
        hosts.get(2),
        ApplicationState.STATUS,
        valueFactory.left(Collections.singleton(keyTokens.get(1)), Gossiper.computeExpireTime()));

    assertFalse(tmd.isMember(hosts.get(2)));
    assertFalse(tmd.isLeaving(hosts.get(2)));
  }
  @Test
  public void testStateJumpToBootstrap() throws UnknownHostException {
    StorageService ss = StorageService.instance;
    TokenMetadata tmd = ss.getTokenMetadata();
    tmd.clearUnsafe();
    IPartitioner partitioner = RandomPartitioner.instance;
    VersionedValue.VersionedValueFactory valueFactory =
        new VersionedValue.VersionedValueFactory(partitioner);

    ArrayList<Token> endpointTokens = new ArrayList<Token>();
    ArrayList<Token> keyTokens = new ArrayList<Token>();
    List<InetAddress> hosts = new ArrayList<InetAddress>();
    List<UUID> hostIds = new ArrayList<UUID>();

    // create a ring or 5 nodes
    Util.createInitialRing(ss, partitioner, endpointTokens, keyTokens, hosts, hostIds, 7);

    // node 2 leaves
    ss.onChange(
        hosts.get(2),
        ApplicationState.STATUS,
        valueFactory.leaving(Collections.singleton(endpointTokens.get(2))));

    // don't bother to test pending ranges here, that is extensively tested by other
    // tests. Just check that the node is in appropriate lists.
    assertTrue(tmd.isMember(hosts.get(2)));
    assertTrue(tmd.isLeaving(hosts.get(2)));
    assertTrue(tmd.getBootstrapTokens().isEmpty());

    // Bootstrap the node immedidiately to keyTokens.get(4) without going through STATE_LEFT
    Gossiper.instance.injectApplicationState(
        hosts.get(2),
        ApplicationState.TOKENS,
        valueFactory.tokens(Collections.singleton(keyTokens.get(4))));
    ss.onChange(
        hosts.get(2),
        ApplicationState.STATUS,
        valueFactory.bootstrapping(Collections.<Token>singleton(keyTokens.get(4))));

    assertFalse(tmd.isMember(hosts.get(2)));
    assertFalse(tmd.isLeaving(hosts.get(2)));
    assertEquals(hosts.get(2), tmd.getBootstrapTokens().get(keyTokens.get(4)));

    // Bootstrap node hosts.get(3) to keyTokens.get(1)
    Gossiper.instance.injectApplicationState(
        hosts.get(3),
        ApplicationState.TOKENS,
        valueFactory.tokens(Collections.singleton(keyTokens.get(1))));
    ss.onChange(
        hosts.get(3),
        ApplicationState.STATUS,
        valueFactory.bootstrapping(Collections.<Token>singleton(keyTokens.get(1))));

    assertFalse(tmd.isMember(hosts.get(3)));
    assertFalse(tmd.isLeaving(hosts.get(3)));
    assertEquals(hosts.get(2), tmd.getBootstrapTokens().get(keyTokens.get(4)));
    assertEquals(hosts.get(3), tmd.getBootstrapTokens().get(keyTokens.get(1)));

    // Bootstrap node hosts.get(2) further to keyTokens.get(3)
    Gossiper.instance.injectApplicationState(
        hosts.get(2),
        ApplicationState.TOKENS,
        valueFactory.tokens(Collections.singleton(keyTokens.get(3))));
    ss.onChange(
        hosts.get(2),
        ApplicationState.STATUS,
        valueFactory.bootstrapping(Collections.<Token>singleton(keyTokens.get(3))));

    assertFalse(tmd.isMember(hosts.get(2)));
    assertFalse(tmd.isLeaving(hosts.get(2)));
    assertEquals(hosts.get(2), tmd.getBootstrapTokens().get(keyTokens.get(3)));
    assertNull(tmd.getBootstrapTokens().get(keyTokens.get(4)));
    assertEquals(hosts.get(3), tmd.getBootstrapTokens().get(keyTokens.get(1)));

    // Go to normal again for both nodes
    Gossiper.instance.injectApplicationState(
        hosts.get(3),
        ApplicationState.TOKENS,
        valueFactory.tokens(Collections.singleton(keyTokens.get(2))));
    Gossiper.instance.injectApplicationState(
        hosts.get(2),
        ApplicationState.TOKENS,
        valueFactory.tokens(Collections.singleton(keyTokens.get(3))));
    ss.onChange(
        hosts.get(2),
        ApplicationState.STATUS,
        valueFactory.normal(Collections.singleton(keyTokens.get(3))));
    ss.onChange(
        hosts.get(3),
        ApplicationState.STATUS,
        valueFactory.normal(Collections.singleton(keyTokens.get(2))));

    assertTrue(tmd.isMember(hosts.get(2)));
    assertFalse(tmd.isLeaving(hosts.get(2)));
    assertEquals(keyTokens.get(3), tmd.getToken(hosts.get(2)));
    assertTrue(tmd.isMember(hosts.get(3)));
    assertFalse(tmd.isLeaving(hosts.get(3)));
    assertEquals(keyTokens.get(2), tmd.getToken(hosts.get(3)));

    assertTrue(tmd.getBootstrapTokens().isEmpty());
  }