Intellimation - DD3 Examples

DD3 Java Examples

Index of Examples

Art
Birds
Butterflies
Books
Cats
China
Countries
Cosmetology
Education
English Studies
Flight & Space
France
Gifts
Health
Hebrew
Historical Events
Holocaust
Iraq
Ireland
Israel
Italy
Japan
Japanese
>>>Java
Jewish, Judaism
Law
Love Lyrics
Love Poems
Musicology
Nature
New York
People
Photography
Professions
Spain
Weather

(1) The Valentine Shop:

(2) The Rainbow Valentine Shop:

(ExY1)
DD1 EM1 Y1 Y1b EM-Phonebook
DD2 EM2 Y2 Yv_Examples
DD3 EM3 Y3
DD4 EM4 Y4
DD5 EM5 Y5

**** Index of Examples
**** Back to Java Cheat

ASDF
//collections - class exercise Linked List?

//collections - class exercise
class Main
{
    public static void main(String args[]) {
        PhoneBook pb = new PhoneBook();
        Person p1 = new Person("aaaa", "aaaa", "03-0000000");
        Person p2 = new Person("aaaa", "bbbb", "03-0000000");
        Person p3 = new Person("aaaa", "bbbb", "03-1111111");
        pb.add(p1);
        pb.add(p2);
        pb.add(p3);

        pb.print();

        // public final static int byFirstName =1;
        // public final static int byPhone =2;
        // public final static int byLastName = 3
        pb.printSorted(SortBy.FIRST_NAME);
        pb.printSorted(SortBy.LAST_NAME);
        pb.printSorted(SortBy.PHONE);
    }
};

Comparator

//collections - class exercise
import java.util.Comparator;
class OtherPersonComparator implements Comparator
{
    private SortBy m_SortingMode;
    OtherPersonComparator(SortBy nSortedMode)
    {
        m_SortingMode = nSortedMode;
    }

    public int compare(Object o1, Object o2)
    {
        Person p1 = (Person)o1;
        Person p2 = (Person)o2;
        if (m_SortingMode == SortBy.FIRST_NAME)
            return p1.m_firstName.compareTo(p2.m_firstName);
        if (m_SortingMode == SortBy.LAST_NAME)
            return p1.m_lastName.compareTo(p2.m_lastName);
        if (m_SortingMode == SortBy.PHONE)
            return p1.m_phoneNum.compareTo(p2.m_phoneNum);
        throw new RuntimeException("Something is strange here");
    }
}

Person

//collections - class exercise

class Person
{
    String m_firstName;
    String m_lastName;
    String m_phoneNum;

    Person () {
    }

    Person(String first, String last, String phone){
        m_firstName = first;
        m_lastName = last;
        m_phoneNum = phone;
    }
    public String toString() {
        return ("First Name: " + m_firstName + " Last Name: " + m_lastName + " Phone#: " + m_phoneNum + "\n");
    }
    public boolean equals(Object o) {
        if ((!(o instanceof Person)))
            return false;

        Person p = (Person) o;

        return (m_firstName.equals(p.m_firstName) &&
            m_lastName.equals(p.m_lastName) &&
            m_phoneNum.equals(p.m_phoneNum) );
    }
    public int hashCode() {
        return (3*m_firstName.hashCode()) + (5 * m_lastName.hashCode()) + (7 * m_phoneNum.hashCode());
    }

};

Comparator, Comparable

//collections - class exercise
import java.util.*;   // for the collections

class PersonComperator extends Person implements Comparator , Comparable
{

    public final static int byFirstName =1;
    public final static int byPhone =2;
    public final static int byLastName = 3;

    public static int m_CompareBy = byLastName; // default

    // Would have been done nicer if we knew reflection at this stage.
    PersonComperator(Person copiedObj) {
        m_firstName = copiedObj.m_firstName;
        m_lastName = copiedObj.m_lastName;
        m_phoneNum = copiedObj.m_phoneNum;
    }



    public static void setCompareBy(int by) {
        m_CompareBy = by;
    }
    public static int getCompareBy() {
        return m_CompareBy;
    }
    // Implementing the Comperator interface
    // Compare, Returns a negative integer, zero, or a positive integer:
    // as the first argument is less than,
    // equal to, or greater than the second.

    public int compare(Object element1, Object element2)
    {
        //System.out.println("In PersonComperator compare");

        Person p1 = (Person) element1;
        Person p2 = (Person) element2;

        switch (m_CompareBy)
        {
        case byFirstName :
            return (p1.m_firstName.compareTo(p2.m_firstName));

        case byLastName:
            return (p1.m_lastName.compareTo(p2.m_lastName));

        case byPhone:
            return (p1.m_phoneNum.compareTo(p2.m_phoneNum));
        default:
            return 0;

        }

    }

    // implrmrnting Comperable
    public int compareTo(Object other) {
        return compare(this, other);
    }
    public boolean equals(Object obj) {
        //System.out.println("In PersonComperator equals");
        Person p = (Person) this;
        return (p.equals(obj));
    }

    public String toString() {
        switch (m_CompareBy)
        {
        case byFirstName :
            return ("First Name: " + m_firstName + " Last Name: " + m_lastName + " Phone#: " + m_phoneNum + "\n");

        case byLastName:
            return ("Last Name: " + m_lastName + " First Name: " + m_firstName + " Phone#: " + m_phoneNum + "\n");

        case byPhone:
            return ("Phone#: " + m_phoneNum + " First Name: " + m_firstName + " Last Name: " + m_lastName + "\n" );
        default:
            return "";

        }

    }
};

Phonebook hashset List ArrayList

//collections - class exercise

import java.util.*;   // for the collections

class PhoneBook
{
    List m_hashset;

    PhoneBook () {
        m_hashset = new ArrayList();
    }

    // Phone book interface according to the requirements
    public boolean add(Person object) {
        //if (!( object instanceof Person))
        //    return;
//        PersonComperator personComperator = new PersonComperator((Person)object);
        return m_hashset.add(object);
    }
    public void print() {
        System.out.println("In Regular Print");

        System.out.println(m_hashset); // each set member will know how
                                        // to print itself
        /*
        Iterator iter = m_hashset.iterator();
        while(iter.hasNext())
            System.out.print(iter.next());
        */

    }
    public void printSorted(SortBy whichField) {

        System.out.println("In Sorted Print, sorted by" + whichField);
//        PersonComperator.setCompareBy(whatBy);
        OtherPersonComparator comparator =
                        new OtherPersonComparator(whichField);
//        TreeSet set = new TreeSet(comparator);
//        set.addAll(m_hashset);
        Collections.sort(m_hashset, comparator);

//        TreeSet tset = new TreeSet(m_hashset);
        System.out.println(m_hashset);
    }
};

Sortby

//collections - class exercise

class SortBy
{
    private String m_sDesc;
    public String toString() { return m_sDesc; }
    private SortBy(String sDesc) { m_sDesc = sDesc;}
    public static final SortBy FIRST_NAME = new SortBy("Sorting by first name");
    public static final SortBy LAST_NAME = new SortBy("last name");
    public static final SortBy PHONE = new SortBy("phone");
};

//dir list Iterator Time (current.Time.Millis

// dir list

import java.util.List;
import java.util.LinkedList;
import java.util.ArrayList;
import java.util.Iterator;
import java.util.ListIterator;

class Ex1
{
    public static void main(String args[])
    {

        List l = new ArrayList();
        for (int i = 0 ; i < 1000000 ; ++i )
        {
            l.add("This is a string");
        }
        System.out.println("Start Iteration");
        long lStart = System.currentTimeMillis();
        Iterator iter = l.iterator();
        //while(iter.hasNext())
        //    iter.next();//returns the object
        int nSize = l.size();
        for (int i = 0 ; i < nSize ; ++i)
        {
            l.get(i);
        }
        long lEnd = System.currentTimeMillis();
        System.out.println(lEnd - lStart);

    }
};

dir map
TreeMap

//dir map

import java.util.*;

class Main
{
    public static void main(String args[])
    {
        TreeMap map = new TreeMap ();
        map.put("David", new Person("david", "sdff", "1233454"));
        map.put("David1", new Person("david", "sdff", "1233454"));
        map.put("David2", new Person("david", "sdff", "1233454"));
        map.put("David", new Person("dav333id", "sdff", "1233454"));
        map.put("David4", new Person("david", "sdff", "1233454"));

        //show all keys.
        Set keySet = map.keySet();
        Iterator iter = keySet.iterator();
        print(iter);

        //Show all values
        Collection col = map.values();
        iter = col.iterator();
        print(iter);

        //Itetrate through entry set
        Set entryset = map.entrySet();
        iter = entryset.iterator();
        while(iter.hasNext())
        {
            Map.Entry entry = (Map.Entry)iter.next();
            System.out.println(entry.getKey() + " --> "
                                        + entry.getValue());
        }
    }

    private static void print(Iterator iter)
    {
        while(iter.hasNext())
            System.out.println(iter.next());
    }
}

//dir map

////dir map

class Person
{
    String m_firstName;
    String m_lastName;
    String m_phoneNum;

    Person(String first, String last, String phone){
        m_firstName = first;
        m_lastName = last;
        m_phoneNum = phone;
    }
    public String toString() {
        return ("First Name: " + m_firstName + " Last Name: " + m_lastName + " Phone#: " + m_phoneNum + "\n");
    }
    public boolean equals(Object o) {
        if ((!(o instanceof Person)))
            return false;

        Person p = (Person) o;

        return (m_firstName.equals(p.m_firstName) &&
            m_lastName.equals(p.m_lastName) &&
            m_phoneNum.equals(p.m_phoneNum) );
    }
    public int hashCode() {
        return (3*m_firstName.hashCode()) + (5 * m_lastName.hashCode()) + (7 * m_phoneNum.hashCode());
    }
};

dir collections/set
iterator set

//dir collections/set

import java.util.*;
class Ex1
{
    public static void main(String args[])
    {
        Set s = new HashSet();
        for (int i = 0 ; i < args.length ;++i )
            s.add(new Person(args[i]));

        Iterator iter = s.iterator();
        while(iter.hasNext())
        {
            Object o = iter.next();
            System.out.println(o); //--> inside println --> o.toString();
        }
    }
};

//dir collections/set

class Person
{
    private String m_sName;

    Person(String sName)
    {
        m_sName = sName;
    }

    public boolean equals(Object o)
    {
        System.out.println("In Equals");
        if (!(o instanceof Person))
            return false;
        return m_sName.equals(((Person)o).m_sName);
    }

    public int hashCode()
    {
        System.out.println("In Person's Hashcode");
        return m_sName.hashCode();
    }

    public String toString()
    {
        return m_sName;
    }
};

//dir collections/set/ex2
Comparator

//dir collections/set/ex2
import java.util.*;
class Ex1
{
    public static void main(String args[])
    {
        //Set s = new TreeSet();
        Set s = new TreeSet(new PersonComparator());
        for (int i = 0 ; i < args.length ;++i )
            s.add(new Person(args[i]));

        Iterator iter = s.iterator();
        while(iter.hasNext())
        {
            Object o = iter.next();
            System.out.println(o); //--> inside println --> o.toString();
        }
    }
};

Comparable

//dir collections/set/ex2

class Person implements Comparable
{
    private String m_sName;

    Person(String sName)
    {
        m_sName = sName;
    }

    public int compareTo(Object other)
    {
        System.out.println("On CompareTo");
        Person p = (Person)other; //Can throw an exception if other is not Person
        return m_sName.compareTo(p.m_sName);
    }

    public boolean equals(Object o)
    {
        System.out.println("In Equals");
        if (!(o instanceof Person))
            return false;
        return m_sName.equals(((Person)o).m_sName);
    }

    public int hashCode()
    {
        System.out.println("In Person's Hashcode");
        return m_sName.hashCode();
    }

    public String toString()
    {
        return m_sName;
    }
};

Comparator2

//dir collections/set/ex2

import java.util.Comparator;

class PersonComparator implements Comparator
{
    public int compare(Object o1, Object o2)
    {
        Person p1 = (Person)o1;
        Person p2 = (Person)o2;
        return p2.compareTo(p1); //return age differecnes etc.
    }
};

dir ... root (day 3 didi)
a

//dir ... root (day 3 didi)
class Person
{
    String m_sName;
    String m_sPhone;
    void setPhoneNumber(String phone)
    {
        m_sPhone = phone;
    }

    void setName(String name)
    {
        m_sName = name;
    }

    void print()
    {
        System.out.println("Name = " + m_sName +
                            " Phone = " + m_sPhone);
    }
};

a
a

//dir ... root (day 3 didi)
class PhoneBook
{
    Person arr[] = new Person[100];
    //Dim arr as Person(100)
    int nNumOfPersons = 0;

    void addPerson(Person p) //param0 -> this (PhoneBook), Person p
    {
        if (nNumOfPersons < arr.length)
        {
            arr[nNumOfPersons++] = p;
        }
    }

    void print()
    {
        System.out.println("Num of persons in book = "
            + nNumOfPersons);
        for (int i = 0 ; i < nNumOfPersons ; ++i )
        {
            Person personToPrint = arr[i];
            personToPrint.print();
            //arr[i].print();
        }
    }
};

a
a

//dir ... root (day 3 didi)

class PhoneBook
{
    Person arr[] = new Person[100];
    //Dim arr as Person(100)
    int nNumOfPersons = 0;

    void addPerson(Person p) //param0 -> this (PhoneBook), Person p
    {
        if (nNumOfPersons < arr.length)
        {
            arr[nNumOfPersons++] = p;
        }
    }

    void print()
    {
        System.out.println("Num of persons in book = "
            + nNumOfPersons);
        for (int i = 0 ; i < nNumOfPersons ; ++i )
        {
            Person personToPrint = arr[i];
            personToPrint.print();
            //arr[i].print();
        }
    }
};

a
a

//dir ... root (day 3 didi)
class Test
{
    public static void main(String args[])
    {
        int arr[] = new int[Integer.MAX_VALUE / 1000];
    }
};

a
a

//dir ... root (day 3 didi)
class Ex2
{
    public static void main(String args[])
    {
        /*
        int i = 0;
        int j = 33;
        boolean b = true;
        long l = 3l;
        double d = 2.3;
        float f = 2.3f;
        System.out.println(j);
        */
        int nUserVal = Integer.parseInt(args[0]);
        nUserVal += 10;
        System.out.println("will print 10 times");
    for (int i = 0 ; i < 9 ; i = i + 1)
        System.out.println(nUserVal);
    }
};

String methods

//dir ... root (day 3 didi)
class Ex3
{
    public static void main(String args[])
    {
        String s1 = "Hello";
        String s2 = " World".toUpperCase();
        String s3 = s1 + s2;
        //String s4 = s1;
        //s4 += s2;
        String s4 = s3;
        s4 += s4;
        s4 = s4.toUpperCase();
        s4 = s4.trim();
        s4 = s4.subString(2);
        System.out.println(s4);
    }
};

a
a

//dir ... root (day 3 didi)

class Ex4
{
    public static void main(String args[])
    {
        String s = "";
        for (int i = 0 ; i < 100000 ; ++i)
        {
            s += i;
        }
    }
};

/***

Method void main(java.lang.String[])
   0 ldc #2 <String "">
   2 astore_1
   3 iconst_0
   4 istore_2
   5 goto 30
   8 new #3 <Class java.lang.StringBuffer>
11 dup
12 invokespecial #4 <Method java.lang.StringBuffer()>
15 aload_1
16 invokevirtual #5 <Method java.lang.StringBuffer append(java.
19 iload_2
20 invokevirtual #6 <Method java.lang.StringBuffer append(int)>
23 invokevirtual #7 <Method java.lang.String toString()>
26 astore_1
27 iinc 2 1
30 iload_2
31 ldc #8 <Integer 100000>
33 if_icmplt 8
36 return
*/

StringBuffer

//dir ... root (day 3 didi)

class Ex4Improved
{
    public static void main(String args[])
    {
        StringBuffer s = new StringBuffer();
        for (int i = 0 ; i < 100000 ; ++i)
        {
            s.append(i);
        }
        String s2 = s.toString();
    }
}
/***
Method void main(java.lang.String[])
   0 new #2 <Class java.lang.StringBuffer>
   3 dup
   4 invokespecial #3 <Method java.lang.StringBuffer()>
   7 astore_1
   8 iconst_0
   9 istore_2
10 goto 22
13 aload_1
14 iload_2
15 invokevirtual #4 <Method java.lang.StringBuffer append(int)>
18 pop
19 iinc 2 1
22 iload_2
23 ldc #5 <Integer 100000>
25 if_icmplt 13
28 aload_1
29 invokevirtual #6 <Method java.lang.String toString()>
32 astore_3
33 return
*/

a
a

//dir ... root (day 3 didi)
class Ex5
{
    public static void main(String args[])
    {
        int arr[];
        arr = new int[3];
        int temp[] = new int[6];
        for (int i = 0 ; i < 3 ; ++i)
        {
            temp[i] = arr[i];
        }
        arr = temp;
        byte b[] = new byte[1024];

    }
};

a
Getting Arguments from Command Line or Command Line Arguments

//dir ... root (day 3 didi)
class Ex6
{
    public static void main(String args[])
    {
        for (int i = 0 ; i < args.length ; ++i )
        {
            System.out.println(args[i]);
        }
    }
};

If Statement

//dir ... root (day 3 didi)
class IfStatement
{
    public static void main(String args[])
    {
        int i = args.length;
        if (i > 0)
        {
            System.out.println(args[0]);
        }
    }
};

Thread.sleep

//dir ... root (day 3 didi)
class Main
{
    public static void main(String args[]) throws InterruptedException
    {
        System.out.println("Hello Java");
        Thread.sleep(10000);
        System.out.println("Done");
    }
};

Add any number of numbers from commandline

//dir ... root (day 3 didi)

class AddFourNumbers {
/*

int[] sArray = { 1,2,3,4};
int total = 0;
total = sArray[1]+ sArray[2] + sArray[3] + sArray[4];
System.out.println(total);
*/
/////////////////////////
    public static void main(String[] args)
    {
        int Sum = 0;
        for (int i = 0 ; i < args.length ; i = i + 1)
        {
            int NextVal = Integer.parseInt(args[i]);
            Sum = Sum + NextVal; //Sum += NextVal;
        }
        System.out.println(Sum);
    }
}

a
a

//dir ... root (day 3 didi)

a
a

//dir ... root (day 3 didi)

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