Example usage for java.util Collections singleton

List of usage examples for java.util Collections singleton

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Introduction

In this page you can find the example usage for java.util Collections singleton.

Prototype

public static <T> Set<T> singleton(T o)

Source Link

Document

Returns an immutable set containing only the specified object.

Usage

From source file:MainClass.java

public static void main(String[] a) {
    System.out.println(Collections.singletonList("a"));
    System.out.println(Collections.singleton("a"));
    System.out.println(Collections.singletonMap("a", "b"));

}

From source file:MainClass.java

public static void main(String args[]) {
    String init[] = { "One", "Two", "Three", "One", "Two", "Three" };
    List list1 = new ArrayList(Arrays.asList(init));
    List list2 = new ArrayList(Arrays.asList(init));
    list1.remove("One");
    System.out.println(list1);//from   www  .j  av a2  s  .co m
    list2.removeAll(Collections.singleton("One"));
    System.out.println(list2);
}

From source file:Main.java

public static void main(String[] args) {
    String givenstring = "this is a test this is a another test";
    String[] words = givenstring.split(" ");

    ArrayList<String> arr = new ArrayList<String>();
    for (int i = 0; i < words.length; i++) {
        arr.add(words[i]);/*from  w  ww . j  a va 2  s. c om*/
    }
    while (arr.size() != 0) {
        String word = arr.get(0);
        int frequency = Collections.frequency(arr, word);
        arr.removeAll(Collections.singleton(word));
        System.out.println(word + frequency);
    }
}

From source file:Main.java

public static void main(String args[]) {
    String init[] = { "One", "Two", "Three", "One", "Two", "Three" };

    // create two lists
    List<String> list1 = new ArrayList<String>(Arrays.asList(init));
    List<String> list2 = new ArrayList<String>(Arrays.asList(init));

    // remove from list1
    list1.remove("One");
    System.out.println("List1 value: " + list1);

    // remove from list2 using singleton
    list2.removeAll(Collections.singleton("One"));
    System.out.println("The SingletonList is :" + list2);
}

From source file:MainClass.java

public static void main(String args[]) throws Exception {
    CertificateFactory cf = CertificateFactory.getInstance("X.509");
    List mylist = new ArrayList();
    FileInputStream in = new FileInputStream(args[0]);
    Certificate c = cf.generateCertificate(in);
    mylist.add(c);//w  w w. j av a2s. c  o m

    CertPath cp = cf.generateCertPath(mylist);

    Certificate trust = cf.generateCertificate(in);
    TrustAnchor anchor = new TrustAnchor((X509Certificate) trust, null);
    PKIXParameters params = new PKIXParameters(Collections.singleton(anchor));
    params.setRevocationEnabled(false);
    CertPathValidator cpv = CertPathValidator.getInstance("PKIX");
    PKIXCertPathValidatorResult result = (PKIXCertPathValidatorResult) cpv.validate(cp, params);
    System.out.println(result);
}

From source file:io.kodokojo.monitor.Launcher.java

public static void main(String[] args) {

    Injector propertyInjector = Guice.createInjector(new CommonsPropertyModule(args), new PropertyModule());
    MicroServiceConfig microServiceConfig = propertyInjector.getInstance(MicroServiceConfig.class);
    LOGGER.info("Starting Kodo Kojo {}.", microServiceConfig.name());
    Injector commonsServicesInjector = propertyInjector.createChildInjector(new UtilityServiceModule(),
            new EventBusModule(), new DatabaseModule(), new SecurityModule(), new CommonsHealthCheckModule());

    Injector marathonInjector = null;//from  w w  w.  ja va  2 s  .c  o m
    OrchestratorConfig orchestratorConfig = propertyInjector.getInstance(OrchestratorConfig.class);
    if (MOCK.equals(orchestratorConfig.orchestrator())) {
        marathonInjector = commonsServicesInjector.createChildInjector(new AbstractModule() {
            @Override
            protected void configure() {
                //
            }

            @Singleton
            @Provides
            BrickStateLookup provideBrickStateLookup() {
                return new BrickStateLookup() {

                    private int cpt = 0;

                    @Override
                    public Set<BrickStateEvent> lookup() {
                        return Collections.singleton(generateBrickStateEvent());
                    }

                    public BrickStateEvent generateBrickStateEvent() {
                        BrickStateEvent.State[] states = BrickStateEvent.State.values();
                        int index = RandomUtils.nextInt(states.length);
                        BrickStateEvent.State state = states[index];

                        return new BrickStateEvent("1234", "build-A", BrickType.CI.name(), "jenkins", state,
                                "1.65Z3.1");
                    }
                };
            }
        });
    } else {
        marathonInjector = commonsServicesInjector.createChildInjector(new AbstractModule() {
            @Override
            protected void configure() {
                //
            }

            @Singleton
            @Provides
            BrickStateLookup provideBrickStateLookup(MarathonConfig marathonConfig,
                    ProjectFetcher projectFectcher, BrickFactory brickFactory, BrickUrlFactory brickUrlFactory,
                    OkHttpClient httpClient) {
                return new MarathonBrickStateLookup(marathonConfig, projectFectcher, brickFactory,
                        brickUrlFactory, httpClient);
            }

        });
    }

    Injector servicesInjector = marathonInjector.createChildInjector(new ServiceModule());

    ApplicationLifeCycleManager applicationLifeCycleManager = servicesInjector
            .getInstance(ApplicationLifeCycleManager.class);
    Runtime.getRuntime().addShutdownHook(new Thread() {
        @Override
        public void run() {
            super.run();
            LOGGER.info("Stopping services.");
            applicationLifeCycleManager.stop();
            LOGGER.info("All services stopped.");
        }
    });

    EventBus eventBus = servicesInjector.getInstance(EventBus.class);
    eventBus.connect();
    //  Init repository.
    BrickStateLookup brickStateLookup = servicesInjector.getInstance(BrickStateLookup.class);
    BrickStateEventRepository repository = servicesInjector.getInstance(BrickStateEventRepository.class);
    Set<BrickStateEvent> brickStateEvents = brickStateLookup.lookup();
    repository.compareAndUpdate(brickStateEvents);

    HttpHealthCheckEndpoint httpHealthCheckEndpoint = servicesInjector
            .getInstance(HttpHealthCheckEndpoint.class);
    httpHealthCheckEndpoint.start();

    ActorSystem actorSystem = servicesInjector.getInstance(ActorSystem.class);
    ActorRef actorRef = servicesInjector.getInstance(ActorRef.class);
    actorSystem.scheduler().schedule(Duration.Zero(), Duration.create(1, TimeUnit.MINUTES), actorRef, "Tick",
            actorSystem.dispatcher(), ActorRef.noSender());
    LOGGER.info("Kodo Kojo {} started.", microServiceConfig.name());

}

From source file:joshelser.as2015.ingester.CategoryUpdater.java

public static void main(String[] args) throws Exception {
    JCommander commander = new JCommander();
    final Opts options = new Opts();
    commander.addObject(options);//w  w w . j a  v  a  2  s .  c  o m

    commander.setProgramName("Query");
    try {
        commander.parse(args);
    } catch (ParameterException ex) {
        commander.usage();
        System.err.println(ex.getMessage());
        System.exit(1);
    }

    ClientConfiguration conf = ClientConfiguration.loadDefault();
    if (null != options.clientConfFile) {
        conf = new ClientConfiguration(new PropertiesConfiguration(options.clientConfFile));
    }
    conf.withInstance(options.instanceName).withZkHosts(options.zookeepers);

    ZooKeeperInstance inst = new ZooKeeperInstance(conf);
    Connector conn = inst.getConnector(options.user, new PasswordToken(options.password));

    BatchScanner bs = conn.createBatchScanner(options.table, Authorizations.EMPTY, 16);
    BatchWriter bw = conn.createBatchWriter(options.table, new BatchWriterConfig());
    try {
        bs.setRanges(Collections.singleton(new Range()));
        final Text categoryText = new Text("category");
        bs.fetchColumnFamily(categoryText);

        final Text categoryName = new Text("name");
        final Text row = new Text();
        for (Entry<Key, Value> entry : bs) {
            entry.getKey().getRow(row);
            Mutation m = new Mutation(row);
            m.put(categoryText, categoryName, entry.getValue());

            bw.addMutation(m);
        }
    } finally {
        bs.close();
        bw.close();
    }
}

From source file:joshelser.as2015.query.Query.java

public static void main(String[] args) throws Exception {
    JCommander commander = new JCommander();
    final Opts options = new Opts();
    commander.addObject(options);/*from ww  w. jav  a2s . co m*/

    commander.setProgramName("Query");
    try {
        commander.parse(args);
    } catch (ParameterException ex) {
        commander.usage();
        System.err.println(ex.getMessage());
        System.exit(1);
    }

    ClientConfiguration conf = ClientConfiguration.loadDefault();
    if (null != options.clientConfFile) {
        conf = new ClientConfiguration(new PropertiesConfiguration(options.clientConfFile));
    }
    conf.withInstance(options.instanceName).withZkHosts(options.zookeepers);

    ZooKeeperInstance inst = new ZooKeeperInstance(conf);
    Connector conn = inst.getConnector(options.user, new PasswordToken(options.password));

    BatchScanner bs = conn.createBatchScanner(options.table, Authorizations.EMPTY, 16);
    try {
        bs.setRanges(Collections.singleton(new Range()));
        final Text categoryText = new Text("category");
        bs.fetchColumn(categoryText, new Text("name"));
        bs.fetchColumn(new Text("review"), new Text("score"));
        bs.fetchColumn(new Text("review"), new Text("userId"));

        bs.addScanIterator(new IteratorSetting(50, "wri", WholeRowIterator.class));
        final Text colf = new Text();
        Map<String, List<Integer>> scoresByUser = new HashMap<>();
        for (Entry<Key, Value> entry : bs) {
            SortedMap<Key, Value> row = WholeRowIterator.decodeRow(entry.getKey(), entry.getValue());
            Iterator<Entry<Key, Value>> iter = row.entrySet().iterator();
            if (!iter.hasNext()) {
                // row was empty
                continue;
            }
            Entry<Key, Value> categoryEntry = iter.next();
            categoryEntry.getKey().getColumnFamily(colf);
            if (!colf.equals(categoryText)) {
                throw new IllegalArgumentException("Unknown!");
            }
            if (!categoryEntry.getValue().toString().equals("books")) {
                // not a book review
                continue;
            }

            if (!iter.hasNext()) {
                continue;
            }
            Entry<Key, Value> reviewScore = iter.next();
            if (!iter.hasNext()) {
                continue;
            }
            Entry<Key, Value> reviewUserId = iter.next();

            String userId = reviewUserId.getValue().toString();
            if (userId.equals("unknown")) {
                // filter unknow user id
                continue;
            }

            List<Integer> scores = scoresByUser.get(userId);
            if (null == scores) {
                scores = new ArrayList<>();
                scoresByUser.put(userId, scores);
            }
            scores.add(Float.valueOf(reviewScore.getValue().toString()).intValue());
        }

        for (Entry<String, List<Integer>> entry : scoresByUser.entrySet()) {
            int sum = 0;
            for (Integer val : entry.getValue()) {
                sum += val;
            }

            System.out.println(entry.getKey() + " => " + new Float(sum) / entry.getValue().size());
        }
    } finally {
        bs.close();
    }
}

From source file:joshelser.as2015.ingester.Ingester.java

public static void main(String[] args) throws Exception {
    JCommander commander = new JCommander();
    final Opts options = new Opts();
    commander.addObject(options);/*  w  ww .  j  a va  2s . co m*/

    commander.setProgramName("Amazon Review Parser");
    try {
        commander.parse(args);
    } catch (ParameterException ex) {
        commander.usage();
        System.err.println(ex.getMessage());
        System.exit(1);
    }

    Registry registry = new RegistryImpl();
    registry.add(new ReviewMapping());

    ClientConfiguration conf = ClientConfiguration.loadDefault();
    if (null != options.clientConfFile) {
        conf = new ClientConfiguration(new PropertiesConfiguration(options.clientConfFile));
    }
    conf.withInstance(options.instanceName).withZkHosts(options.zookeepers);

    ZooKeeperInstance inst = new ZooKeeperInstance(conf);
    Connector conn = inst.getConnector(options.user, new PasswordToken(options.password));
    if (!conn.tableOperations().exists(options.table)) {
        conn.tableOperations().create(options.table);
    }

    log.info("Writing data from {}", options.file);

    long count = 0;
    try (BufferedReader reader = new BufferedReader(new FileReader(options.file));
            Store store = new StoreImpl(registry, conn, options.table)) {
        List<String> schema = parseArray(readLine(reader));

        String[] record;
        while ((record = readLine(reader)) != null) {
            try {
                List<String> values = parseArray(record);
                CsvReview review = new CsvReview(schema, values);
                store.write(Collections.singleton(review));
                count++;
            } catch (Exception e) {
                log.error("Failed to parse '" + Arrays.toString(record) + "'", e);
            }
        }
    }

    log.info("Wrote {} records for {}", count, options.file);
}

From source file:com.tamingtext.tagging.LuceneCategoryExtractor.java

public static void main(String[] args) throws IOException {
    DefaultOptionBuilder obuilder = new DefaultOptionBuilder();
    ArgumentBuilder abuilder = new ArgumentBuilder();
    GroupBuilder gbuilder = new GroupBuilder();

    Option inputOpt = obuilder.withLongName("dir").withRequired(true)
            .withArgument(abuilder.withName("dir").withMinimum(1).withMaximum(1).create())
            .withDescription("The Lucene directory").withShortName("d").create();

    Option outputOpt = obuilder.withLongName("output").withRequired(false)
            .withArgument(abuilder.withName("output").withMinimum(1).withMaximum(1).create())
            .withDescription("The output directory").withShortName("o").create();

    Option maxOpt = obuilder.withLongName("max").withRequired(false)
            .withArgument(abuilder.withName("max").withMinimum(1).withMaximum(1).create())
            .withDescription(//www  . j  av a  2s  . co m
                    "The maximum number of documents to analyze.  If not specified, then it will loop over all docs")
            .withShortName("m").create();

    Option fieldOpt = obuilder.withLongName("field").withRequired(true)
            .withArgument(abuilder.withName("field").withMinimum(1).withMaximum(1).create())
            .withDescription("The field in the index").withShortName("f").create();

    Option helpOpt = obuilder.withLongName("help").withDescription("Print out help").withShortName("h")
            .create();

    Group group = gbuilder.withName("Options").withOption(inputOpt).withOption(outputOpt).withOption(maxOpt)
            .withOption(fieldOpt).create();

    try {
        Parser parser = new Parser();
        parser.setGroup(group);
        CommandLine cmdLine = parser.parse(args);

        if (cmdLine.hasOption(helpOpt)) {
            CommandLineUtil.printHelp(group);
            return;
        }

        File inputDir = new File(cmdLine.getValue(inputOpt).toString());

        if (!inputDir.isDirectory()) {
            throw new IllegalArgumentException(inputDir + " does not exist or is not a directory");
        }

        long maxDocs = Long.MAX_VALUE;
        if (cmdLine.hasOption(maxOpt)) {
            maxDocs = Long.parseLong(cmdLine.getValue(maxOpt).toString());
        }

        if (maxDocs < 0) {
            throw new IllegalArgumentException("maxDocs must be >= 0");
        }

        String field = cmdLine.getValue(fieldOpt).toString();

        PrintWriter out = null;
        if (cmdLine.hasOption(outputOpt)) {
            out = new PrintWriter(new FileWriter(cmdLine.getValue(outputOpt).toString()));
        } else {
            out = new PrintWriter(new OutputStreamWriter(System.out, "UTF-8"));
        }

        dumpDocumentFields(inputDir, field, maxDocs, out);

        IOUtils.close(Collections.singleton(out));
    } catch (OptionException e) {
        log.error("Exception", e);
        CommandLineUtil.printHelp(group);
    }

}