Example usage for java.util ArrayList ArrayList

List of usage examples for java.util ArrayList ArrayList

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Introduction

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

Prototype

public ArrayList()

Source Link

Document

Constructs an empty list with an initial capacity of ten.

Usage

From source file:Main.java

public static void main(final String[] args) {
    final List<String> asu = new ArrayList<String>();
    asu.add("2");
    asu.add("11");
    asu.add("7");
    asu.add("10");
    asu.add("7");
    asu.add("12");
    asu.add("2");
    asu.add("11");
    asu.add("11");
    asu.add("7");
    asu.add("7");
    asu.add("7");

    List<String> list = new ArrayList<String>();
    Map<String, Integer> counts = new HashMap<String, Integer>();
    list.addAll(asu);/*from   w  w  w .  j  a v a  2  s.co  m*/
    for (String item : list) {
        Integer count = counts.get(item);
        if (count == null) {
            count = 1;
        } else {
            count = count + 1;
        }
        counts.put(item, count);
    }
    Collections.sort(asu, new Comparator<String>() {
        @Override
        public int compare(final String left, final String right) {
            int result = counts.get(left).compareTo(counts.get(right));
            if (result == 0) {
                result = left.compareTo(right);
            }
            return result;
        }
    });
    System.out.println(asu);
}

From source file:Main.java

public static void main(String[] args) {
    List<Student> members = new ArrayList<>();

    members.add(new Student("P", Sex.MALE, 12, "p@g.com"));
    members.add(new Student("J", Sex.MALE, 42, "j@g.com"));
    members.add(new Student("K", Sex.FEMALE, 22, "k@g.com"));
    members.add(new Student("L", Sex.FEMALE, 52, "l@g.com"));

    for (Sex gender : Sex.values()) {
        System.out.println("All " + gender + ":");
        processMembersWithFunction(members, p -> p.getGender() == gender, Student::getName,
                System.out::println);
    }//ww  w . ja va2s .com

    System.out.println("All FEMALE over 30:");
    processMembersWithFunction(members, p -> p.getGender() == Sex.FEMALE && p.getAge() > 30, Student::getName,
            System.out::println);
}

From source file:NewStyle.java

public static void main(String args[]) {

    // Now, list holds references of type String. 
    ArrayList<String> list = new ArrayList<String>();

    list.add("one");
    list.add("two");
    list.add("three");
    list.add("four");

    // Notice that Iterator is also generic. 
    Iterator<String> itr = list.iterator();

    // The following statement will now cause a compile-time eror. 
    //    Iterator<Integer> itr = list.iterator(); // Error! 

    while (itr.hasNext()) {
        String str = itr.next(); // no cast needed 

        // Now, the following line is a compile-time, 
        // rather than runtime, error. 
        //    Integer i = itr.next(); // this won't compile 

        System.out.println(str + " is " + str.length() + " chars long.");
    }// w w w  .  j  a  v  a2  s  . co m
}

From source file:Main.java

public static void main(String[] args) {
    String s = "(123, 234; 345, 456) (567, 788; 899, 900)";
    Matcher m = Pattern.compile("\\d+").matcher(s);
    List<Integer> numbers = new ArrayList<Integer>();
    while (m.find()) {
        numbers.add(Integer.parseInt(m.group()));
    }/*from   www .  jav  a  2s . co  m*/
    System.out.println(numbers);
}

From source file:Main.java

License:asdf

public static void main(String[] args) {
    int howManyWords = 2;
    List<String> listOfWords = new ArrayList<>();
    Random random = new Random();
    listOfWords.addAll(Arrays.asList(randomMessages));
    List<String> selectedRandomMessages = new ArrayList<>();
    for (int i = 0; i < howManyWords; i++) {
        int randomNumber = random.nextInt(listOfWords.size());
        String randomItem = listOfWords.get(randomNumber);
        selectedRandomMessages.add(randomItem);
        listOfWords.remove(randomItem);//from  w w  w  .j a v a 2 s.  c om
    }
    System.out.println(selectedRandomMessages);
}

From source file:Main.java

public static void main(String[] args) {
    Collection<String> c = Collections.synchronizedCollection(new ArrayList<String>());
    List<String> list = Collections.synchronizedList(new ArrayList<String>());
    Set<String> s = Collections.synchronizedSet(new HashSet<String>());
    Map<String, String> m = Collections.synchronizedMap(new HashMap<String, String>());
}

From source file:MainClass.java

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

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

    al.add("C");//  w  w w .j ava  2  s  . c o  m
    al.add("A");
    al.add("E");
    al.add("B");
    al.add("D");
    al.add("F");
    al.add(1, "A2");

    System.out.println("Size of al after additions: " + al.size());

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

    al.remove("F");
    al.remove(2);

    System.out.println("Size of al after deletions: " + al.size());
    System.out.println("Contents of al: " + al);
}

From source file:Main.java

public static void main(String[] argv) {
    List<DayOfWeek> list = new ArrayList<>();

    list = (List<DayOfWeek>) Stream.of(Month.values()).map(month -> LocalDate.now().withYear(2010).with(month)
            .with(TemporalAdjusters.lastDayOfMonth()).getDayOfWeek()).collect(Collectors.toList());

    System.out.println(list);/*from w w  w. j  a  v  a2  s  .c  o  m*/
}

From source file:Main.java

public static void main(String[] args) {
    List<String> texts = new ArrayList<>();
    texts.add("test");
    texts.add("test");
    Path dest = Paths.get("twinkle.txt");
    Charset cs = Charset.forName("US-ASCII");
    try {/*from w  w  w  .  j  a  v a  2s.co  m*/
        Path p = Files.write(dest, texts, cs, StandardOpenOption.WRITE, StandardOpenOption.CREATE);
        System.out.println("Text was written to " + p.toAbsolutePath());
    } catch (IOException e) {
        e.printStackTrace();
    }
}

From source file:MainClass.java

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

    al.add("C");/* w  w w . ja va  2 s.  c  o  m*/
    al.add("A");
    al.add("E");
    al.add("B");
    al.add("D");
    al.add("F");

    System.out.print("Original contents of al: ");
    Iterator<String> itr = al.iterator();
    while (itr.hasNext()) {
        String element = itr.next();
        System.out.print(element + " ");
    }
    System.out.println();

    ListIterator<String> litr = al.listIterator();
    while (litr.hasNext()) {
        String element = litr.next();
        litr.set(element + "+");
    }

    // Now, display the list backwards.
    System.out.print("Modified list backwards: ");
    while (litr.hasPrevious()) {
        String element = litr.previous();
        System.out.print(element + " ");
    }
}