Example usage for java.util ArrayList toArray

List of usage examples for java.util ArrayList toArray

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Introduction

In this page you can find the example usage for java.util ArrayList toArray.

Prototype

@SuppressWarnings("unchecked")
public <T> T[] toArray(T[] a)

Source Link

Document

Returns an array containing all of the elements in this list in proper sequence (from first to last element); the runtime type of the returned array is that of the specified array.

Usage

From source file:ArrayListToArray.java

public static void main(String args[]) {
    ArrayList<Integer> al = new ArrayList<Integer>();

    al.add(1);/*from   ww w.  j  a v  a  2s  .  co m*/
    al.add(2);
    al.add(3);
    al.add(4);

    System.out.println("Contents of al: " + al);

    Integer ia[] = new Integer[al.size()];
    ia = al.toArray(ia);

    int sum = 0;

    for (int i : ia)
        sum += i;

    System.out.println("Sum is: " + sum);
}

From source file:Main.java

public static void main(String[] args) {
    ArrayList<String> al = new ArrayList<String>();
    al.add("Java");
    al.add("SQL");
    al.add("Data");

    System.out.println("ArrayList:" + al);
    String[] s1 = new String[al.size()];

    String[] s2 = al.toArray(s1);

    System.out.println("s1 == s2:" + (s1 == s2));
    System.out.println("s1:" + Arrays.toString(s1));
    System.out.println("s2:" + Arrays.toString(s2));

    s1 = new String[1];
    s1[0] = "hello"; // Store hello in first element

    s2 = al.toArray(s1);//www  .j av  a  2 s  . c  o  m

    System.out.println("s1 == s2:" + (s1 == s2));
    System.out.println("s1:" + Arrays.toString(s1));
    System.out.println("s2:" + Arrays.toString(s2));
}

From source file:MainClass.java

public static void main(String args[]) {

    ArrayList<Integer> al = new ArrayList<Integer>();

    al.add(1);/*  w  w w  .  j  a  v  a  2  s  . c  o m*/
    al.add(2);
    al.add(3);
    al.add(4);

    System.out.println("Contents of al: " + al);

    Integer ia[] = new Integer[al.size()];
    ia = al.toArray(ia);

    int sum = 0;

    for (int i : ia)
        sum += i;

    System.out.println("Sum is: " + sum);
}

From source file:Main.java

public static void main(String[] args) {

    ArrayList<Integer> arrlist = new ArrayList<Integer>();

    arrlist.add(10);/*from w  w w.  j a  va2 s .c  o m*/
    arrlist.add(12);
    arrlist.add(31);
    arrlist.add(49);

    // toArray copies content into other array
    Integer myArray[] = new Integer[arrlist.size()];
    myArray = arrlist.toArray(myArray);

    System.out.println(Arrays.toString(myArray));

}

From source file:dk.dma.nogoservice.Application.java

public static void main(String[] args) {
    SpringApplicationBuilder builder = new SpringApplicationBuilder(Application.class);
    ArrayList<String> profiles = Lists.newArrayList(ApiProfiles.PRODUCTION, ApiProfiles.SECURITY);
    if (Boolean.getBoolean("disableSecurity")) {
        profiles.remove(ApiProfiles.SECURITY);
    }// w  w  w . j  a  v a 2s . c  o  m
    builder.profiles(profiles.toArray(new String[profiles.size()])).headless(false).run(args);
}

From source file:com.tamingtext.classifier.bayes.ClassifyDocument.java

public static void main(String[] args) {
    log.info("Command-line arguments: " + Arrays.toString(args));

    DefaultOptionBuilder obuilder = new DefaultOptionBuilder();
    ArgumentBuilder abuilder = new ArgumentBuilder();
    GroupBuilder gbuilder = new GroupBuilder();

    Option inputOpt = obuilder.withLongName("input").withRequired(true)
            .withArgument(abuilder.withName("input").withMinimum(1).withMaximum(1).create())
            .withDescription("Input file").withShortName("i").create();

    Option modelOpt = obuilder.withLongName("model").withRequired(true)
            .withArgument(abuilder.withName("model").withMinimum(1).withMaximum(1).create())
            .withDescription("Model to use when classifying data").withShortName("m").create();

    Option helpOpt = obuilder.withLongName("help").withDescription("Print out help").withShortName("h")
            .create();/*  www. j av a2  s. c o m*/

    Group group = gbuilder.withName("Options").withOption(inputOpt).withOption(modelOpt).withOption(helpOpt)
            .create();

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

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

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

        if (!inputFile.isFile()) {
            throw new IllegalArgumentException(inputFile + " does not exist or is not a file");
        }

        File modelDir = new File(cmdLine.getValue(modelOpt).toString());

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

        BayesParameters p = new BayesParameters();
        p.set("basePath", modelDir.getCanonicalPath());
        Datastore ds = new InMemoryBayesDatastore(p);
        Algorithm a = new BayesAlgorithm();
        ClassifierContext ctx = new ClassifierContext(a, ds);
        ctx.initialize();

        //TODO: make the analyzer configurable
        StandardAnalyzer analyzer = new StandardAnalyzer(Version.LUCENE_36);
        TokenStream ts = analyzer.tokenStream(null,
                new InputStreamReader(new FileInputStream(inputFile), "UTF-8"));

        ArrayList<String> tokens = new ArrayList<String>(1000);
        while (ts.incrementToken()) {
            tokens.add(ts.getAttribute(CharTermAttribute.class).toString());
        }
        String[] document = tokens.toArray(new String[tokens.size()]);

        ClassifierResult[] cr = ctx.classifyDocument(document, "unknown", 5);

        for (ClassifierResult r : cr) {
            System.err.println(r.getLabel() + "\t" + r.getScore());
        }
    } catch (OptionException e) {
        log.error("Exception", e);
        CommandLineUtil.printHelp(group);
    } catch (IOException e) {
        log.error("IOException", e);
    } catch (InvalidDatastoreException e) {
        log.error("InvalidDataStoreException", e);
    } finally {

    }
}

From source file:edu.oregonstate.eecs.mcplan.ml.KMeans.java

/**
 * @param args//from   www  .  j  av  a2 s  .co m
 */
public static void main(final String[] args) {
    final int nclusters = 2;
    final ArrayList<RealVector> data = new ArrayList<RealVector>();

    for (int x = -1; x <= 1; ++x) {
        for (int y = -1; y <= 1; ++y) {
            data.add(new ArrayRealVector(new double[] { x, y }));
            data.add(new ArrayRealVector(new double[] { x + 10, y + 10 }));
        }
    }

    final KMeans kmeans = new KMeans(nclusters, data.toArray(new RealVector[data.size()])); /* {
                                                                                            @Override
                                                                                            public double distance( final RealVector a, final RealVector b ) {
                                                                                            return a.getL1Distance( b );
                                                                                            }
                                                                                            };
                                                                                            */

    kmeans.run();
    for (int i = 0; i < kmeans.centers().length; ++i) {
        System.out.println("Center " + i + ": " + kmeans.centers()[i]);
        for (int j = 0; j < kmeans.clusters().length; ++j) {
            if (kmeans.clusters()[j] == i) {
                System.out.println("\tPoint " + data.get(j));
            }
        }
    }

}

From source file:POP3Mail.java

public static void main(String[] args) {
    try {/*  w  w  w  .  j  a v a  2s  .c  om*/
        LogManager.getLogManager().readConfiguration(new FileInputStream("logging.properties"));
    } catch (Exception e1) {
        // TODO Auto-generated catch block
        e1.printStackTrace();
    }
    String server = null;
    String username = null;
    String password = null;
    if (new File("mail.properties").exists()) {
        Properties properties = new Properties();
        try {
            properties.load(new FileInputStream(new File("mail.properties")));
            server = properties.getProperty("server");
            username = properties.getProperty("username");
            password = properties.getProperty("password");
            ArrayList<String> list = new ArrayList<String>(
                    Arrays.asList(new String[] { server, username, password }));
            list.addAll(Arrays.asList(args));
            args = list.toArray(new String[list.size()]);
        } catch (FileNotFoundException e) {
            // TODO Auto-generated catch block
            e.printStackTrace();
        } catch (IOException e) {
            // TODO Auto-generated catch block
            e.printStackTrace();
        }
    }
    if (args.length < 3) {
        System.err
                .println("Usage: POP3Mail <pop3 server hostname> <username> <password> [TLS [true=implicit]]");
        System.exit(1);
    }

    server = args[0];
    username = args[1];
    password = args[2];
    String proto = null;
    int messageid = -1;
    boolean implicit = false;
    for (int i = 3; i < args.length; ++i) {
        if (args[i].equals("-m")) {
            i += 1;
            messageid = Integer.parseInt(args[i]);
        }
    }

    // String proto = args.length > 3 ? args[3] : null;
    // boolean implicit = args.length > 4 ? Boolean.parseBoolean(args[4])
    // : false;

    POP3Client pop3;

    if (proto != null) {
        System.out.println("Using secure protocol: " + proto);
        pop3 = new POP3SClient(proto, implicit);
    } else {
        pop3 = new POP3Client();
    }
    pop3.setDefaultPort(110);
    System.out.println("Connecting to server " + server + " on " + pop3.getDefaultPort());

    // We want to timeout if a response takes longer than 60 seconds
    pop3.setDefaultTimeout(60000);
    // suppress login details
    pop3.addProtocolCommandListener(new PrintCommandListener(new PrintWriter(System.out), true));

    try {
        pop3.connect(server);
    } catch (IOException e) {
        System.err.println("Could not connect to server.");
        e.printStackTrace();
        System.exit(1);
    }

    try {
        if (!pop3.login(username, password)) {
            System.err.println("Could not login to server.  Check password.");
            pop3.disconnect();
            System.exit(1);
        }
        PrintWriter printWriter = new PrintWriter(new FileWriter("messages.csv"), true);
        POP3MessageInfo[] messages = null;
        POP3MessageInfo[] identifiers = null;
        if (messageid == -1) {
            messages = pop3.listMessages();
            identifiers = pop3.listUniqueIdentifiers();
        } else {
            messages = new POP3MessageInfo[] { pop3.listMessage(messageid) };
        }
        if (messages == null) {
            System.err.println("Could not retrieve message list.");
            pop3.disconnect();
            return;
        } else if (messages.length == 0) {
            System.out.println("No messages");
            pop3.logout();
            pop3.disconnect();
            return;
        }
        new File("../json").mkdirs();
        int count = 0;
        for (POP3MessageInfo msginfo : messages) {
            if (msginfo.number != identifiers[count].number) {
                throw new RuntimeException();
            }
            msginfo.identifier = identifiers[count].identifier;
            BufferedReader reader = (BufferedReader) pop3.retrieveMessageTop(msginfo.number, 0);
            ++count;
            if (count % 100 == 0) {
                logger.finest(String.format("%d %s", msginfo.number, msginfo.identifier));
            }
            System.out.println(String.format("%d %s", msginfo.number, msginfo.identifier));
            if (reader == null) {
                System.err.println("Could not retrieve message header.");
                pop3.disconnect();
                System.exit(1);
            }
            if (printMessageInfo(reader, msginfo.number, printWriter)) {
            }
        }
        printWriter.close();
        pop3.logout();
        pop3.disconnect();
    } catch (IOException e) {
        e.printStackTrace();
        return;
    }
}

From source file:at.tuwien.ifs.somtoolbox.apps.helper.VectorFileSubsetGenerator.java

public static void main(String[] args) throws IOException, SOMToolboxException {
    // register and parse all options
    JSAPResult config = OptionFactory.parseResults(args, OPTIONS);

    String inputFileName = AbstractOptionFactory.getFilePath(config, "input");
    String classInformationFileName = AbstractOptionFactory.getFilePath(config, "classInformationFile");
    String outputFileName = AbstractOptionFactory.getFilePath(config, "output");

    String[] keepClasses = config.getStringArray("classList");

    boolean skipInstanceNames = false;// config.getBoolean("skipInstanceNames");
    boolean skipInputsWithoutClass = false;// config.getBoolean("skipInputsWithoutClass");
    boolean tabSeparatedClassFile = false;// config.getBoolean("tabSeparatedClassFile");

    String inputFormat = config.getString("inputFormat");
    if (inputFormat == null) {
        inputFormat = InputDataFactory.detectInputFormatFromExtension(inputFileName, "input");
    }/*  w ww.  ja v  a2  s .c  o  m*/
    String outputFormat = config.getString("outputFormat");
    if (outputFormat == null) {
        outputFormat = InputDataFactory.detectInputFormatFromExtension(outputFileName, "output");
    }

    InputData data = InputDataFactory.open(inputFormat, inputFileName);
    if (classInformationFileName != null) {
        SOMLibClassInformation classInfo = new SOMLibClassInformation(classInformationFileName);
        data.setClassInfo(classInfo);
    }
    if (data.classInformation() == null) {
        throw new SOMToolboxException("Need to provide a class information file.");
    }

    Logger.getLogger("at.tuwien.ifs.somtoolbox")
            .info("Retaining elements of classes: " + Arrays.toString(keepClasses));

    ArrayList<InputDatum> subData = new ArrayList<InputDatum>();
    for (int i = 0; i < data.numVectors(); i++) {
        InputDatum datum = data.getInputDatum(i);
        String className = data.classInformation().getClassName(datum.getLabel());
        System.out.println(datum.getLabel() + "=>" + className);
        if (ArrayUtils.contains(keepClasses, className)) {
            subData.add(datum);
        }
    }

    InputData subset = new SOMLibSparseInputData(subData.toArray(new InputDatum[subData.size()]),
            data.classInformation());
    InputDataWriter.write(outputFileName, subset, outputFormat, tabSeparatedClassFile, skipInstanceNames,
            skipInputsWithoutClass);
}

From source file:edu.cmu.lti.oaqa.knn4qa.apps.ExtractDataAndQueryAsSparseVectors.java

public static void main(String[] args) {
    String optKeys[] = { CommonParams.MAX_NUM_QUERY_PARAM, MAX_NUM_DATA_PARAM, CommonParams.MEMINDEX_PARAM,
            IN_QUERIES_PARAM, OUT_QUERIES_PARAM, OUT_DATA_PARAM, TEXT_FIELD_PARAM, TEST_QTY_PARAM, };
    String optDescs[] = { CommonParams.MAX_NUM_QUERY_DESC, MAX_NUM_DATA_DESC, CommonParams.MEMINDEX_DESC,
            IN_QUERIES_DESC, OUT_QUERIES_DESC, OUT_DATA_DESC, TEXT_FIELD_DESC, TEST_QTY_DESC };
    boolean hasArg[] = { true, true, true, true, true, true, true, true };

    ParamHelper prmHlp = null;//from w w  w .ja  v  a  2 s .c  om

    try {

        prmHlp = new ParamHelper(args, optKeys, optDescs, hasArg);

        CommandLine cmd = prmHlp.getCommandLine();
        Options opt = prmHlp.getOptions();

        int maxNumQuery = Integer.MAX_VALUE;

        String tmpn = cmd.getOptionValue(CommonParams.MAX_NUM_QUERY_PARAM);
        if (tmpn != null) {
            try {
                maxNumQuery = Integer.parseInt(tmpn);
            } catch (NumberFormatException e) {
                UsageSpecify(CommonParams.MAX_NUM_QUERY_PARAM, opt);
            }
        }

        int maxNumData = Integer.MAX_VALUE;
        tmpn = cmd.getOptionValue(MAX_NUM_DATA_PARAM);
        if (tmpn != null) {
            try {
                maxNumData = Integer.parseInt(tmpn);
            } catch (NumberFormatException e) {
                UsageSpecify(MAX_NUM_DATA_PARAM, opt);
            }
        }
        String memIndexPref = cmd.getOptionValue(CommonParams.MEMINDEX_PARAM);
        if (null == memIndexPref) {
            UsageSpecify(CommonParams.MEMINDEX_PARAM, opt);
        }
        String textField = cmd.getOptionValue(TEXT_FIELD_PARAM);
        if (null == textField) {
            UsageSpecify(TEXT_FIELD_PARAM, opt);
        }

        textField = textField.toLowerCase();
        int fieldId = -1;
        for (int i = 0; i < FeatureExtractor.mFieldNames.length; ++i)
            if (FeatureExtractor.mFieldNames[i].compareToIgnoreCase(textField) == 0) {
                fieldId = i;
                break;
            }
        if (-1 == fieldId) {
            Usage("Wrong field index, should be one of the following: "
                    + String.join(",", FeatureExtractor.mFieldNames), opt);
        }

        InMemForwardIndex indx = new InMemForwardIndex(
                FeatureExtractor.indexFileName(memIndexPref, FeatureExtractor.mFieldNames[fieldId]));

        BM25SimilarityLucene bm25simil = new BM25SimilarityLucene(FeatureExtractor.BM25_K1,
                FeatureExtractor.BM25_B, indx);

        String inQueryFile = cmd.getOptionValue(IN_QUERIES_PARAM);
        String outQueryFile = cmd.getOptionValue(OUT_QUERIES_PARAM);
        if ((inQueryFile == null) != (outQueryFile == null)) {
            Usage("You should either specify both " + IN_QUERIES_PARAM + " and " + OUT_QUERIES_PARAM
                    + " or none of them", opt);
        }
        String outDataFile = cmd.getOptionValue(OUT_DATA_PARAM);

        tmpn = cmd.getOptionValue(TEST_QTY_PARAM);
        int testQty = 0;
        if (tmpn != null) {
            try {
                testQty = Integer.parseInt(tmpn);
            } catch (NumberFormatException e) {
                UsageSpecify(TEST_QTY_PARAM, opt);
            }
        }

        ArrayList<DocEntry> testDocEntries = new ArrayList<DocEntry>();
        ArrayList<DocEntry> testQueryEntries = new ArrayList<DocEntry>();
        ArrayList<TrulySparseVector> testDocVectors = new ArrayList<TrulySparseVector>();
        ArrayList<TrulySparseVector> testQueryVectors = new ArrayList<TrulySparseVector>();

        if (outDataFile != null) {
            BufferedWriter out = new BufferedWriter(
                    new OutputStreamWriter(CompressUtils.createOutputStream(outDataFile)));

            ArrayList<DocEntryExt> docEntries = indx.getDocEntries();

            for (int id = 0; id < Math.min(maxNumData, docEntries.size()); ++id) {
                DocEntry e = docEntries.get(id).mDocEntry;
                TrulySparseVector v = bm25simil.getDocSparseVector(e, false);
                if (id < testQty) {
                    testDocEntries.add(e);
                    testDocVectors.add(v);
                }
                outputVector(out, v);
            }

            out.close();

        }

        Splitter splitOnSpace = Splitter.on(' ').trimResults().omitEmptyStrings();

        if (outQueryFile != null) {
            BufferedReader inpText = new BufferedReader(
                    new InputStreamReader(CompressUtils.createInputStream(inQueryFile)));
            BufferedWriter out = new BufferedWriter(
                    new OutputStreamWriter(CompressUtils.createOutputStream(outQueryFile)));

            String queryText = XmlHelper.readNextXMLIndexEntry(inpText);

            for (int queryQty = 0; queryText != null && queryQty < maxNumQuery; queryText = XmlHelper
                    .readNextXMLIndexEntry(inpText), queryQty++) {
                Map<String, String> queryFields = null;
                // 1. Parse a query

                try {
                    queryFields = XmlHelper.parseXMLIndexEntry(queryText);
                } catch (Exception e) {
                    System.err.println("Parsing error, offending QUERY:\n" + queryText);
                    throw new Exception("Parsing error.");
                }

                String fieldText = queryFields.get(FeatureExtractor.mFieldsSOLR[fieldId]);

                if (fieldText == null) {
                    fieldText = "";
                }

                ArrayList<String> tmpa = new ArrayList<String>();
                for (String s : splitOnSpace.split(fieldText))
                    tmpa.add(s);

                DocEntry e = indx.createDocEntry(tmpa.toArray(new String[tmpa.size()]));

                TrulySparseVector v = bm25simil.getDocSparseVector(e, true);
                if (queryQty < testQty) {
                    testQueryEntries.add(e);
                    testQueryVectors.add(v);
                }
                outputVector(out, v);
            }

            out.close();
        }

        int testedQty = 0, diffQty = 0;
        // Now let's do some testing
        for (int iq = 0; iq < testQueryEntries.size(); ++iq) {
            DocEntry queryEntry = testQueryEntries.get(iq);
            TrulySparseVector queryVector = testQueryVectors.get(iq);
            for (int id = 0; id < testDocEntries.size(); ++id) {
                DocEntry docEntry = testDocEntries.get(id);
                TrulySparseVector docVector = testDocVectors.get(id);
                float val1 = bm25simil.compute(queryEntry, docEntry);
                float val2 = TrulySparseVector.scalarProduct(queryVector, docVector);
                ++testedQty;
                if (Math.abs(val1 - val2) > 1e5) {
                    System.err.println(
                            String.format("Potential mismatch BM25=%f <-> scalar product=%f", val1, val2));
                    ++diffQty;
                }
            }
        }
        if (testedQty > 0)
            System.out.println(String.format("Tested %d Mismatched %d", testedQty, diffQty));

    } catch (ParseException e) {
        Usage("Cannot parse arguments: " + e, prmHlp != null ? prmHlp.getOptions() : null);
        e.printStackTrace();
    } catch (Exception e) {
        e.printStackTrace();
        System.err.println("Terminating due to an exception: " + e);
        System.exit(1);
    }
}