THIS IS A JAVA PROBLEM, NEEDS TO BE DONE WITH ECLIPSE! 3 java files are give

ID: 3598379 • Letter: #

Question

**THIS IS A JAVA PROBLEM, NEEDS TO BE DONE WITH ECLIPSE!** 3 java files are given.

Java: Write a zip code lookup program. Read a data set of 1,000+ zip codes and city names from a file that contains zip codes and city names in Iowa in random order. Handle lookups by zip code and also reverse lookups by city name. Use a binary search for both lookups.

Four files are provided with the assignment.

1. ZipLookup.java: class containing main method. No modification needed.

2. Item.java: class to store an item. Use string variable ‘key’ for zip code and string variable ‘value’

for city name. No modification needed.

3. LookupTable.java: core class of this assignment. Complete all methods.

4. iazip.txt: zip codes and city names in Iowa.

Submit one source file (LookupTable.java). In other words, ZipLookup.java, Item.java, or iazip.txt are not submitted

Ziplookup:

import java.io.IOException;

import java.io.FileReader;

import java.util.Scanner;

/* The input file has the format

50001

ACKWORTH

50002

ADAIR

50003

ADEL

50005

ALBION

50006

ALDEN

50007

ALLEMAN

50008

. . .

public class ZipLookup

{

public static void main(String[] args) throws IOException

{

Scanner in = new Scanner(System.in);

System.out.println("Enter the name of the zipcode file: ");

String fileName = in.nextLine();

LookupTable table = new LookupTable();

FileReader reader = new FileReader(fileName);

table.read(new Scanner(reader));

boolean more = true;

while (more)

{

System.out.println("Lookup Z)ip, C)ity name, Q)uit?");

String cmd = in.nextLine();

if (cmd.equalsIgnoreCase("Q"))

more = false;

else if (cmd.equalsIgnoreCase("Z"))

{

System.out.println("Enter Zipcode:");

String n = in.nextLine();

System.out.println("City name: " + table.lookup(n) + " ");

}

else if (cmd.equalsIgnoreCase("C"))

{

System.out.println("Enter city name:");

String n = in.nextLine();

Item.java:

/**

An item with a key and a value.

public class Item implements Comparable<Item>

{

private String key;

private String value;

/**

Constructs an Item object.

@param k the key string

@param v the value of the item

public Item(String k, String v)

{

key = k;

value = v;

}

/**

Gets the key.

@return the key

public String getKey()

{

return key;

}

/**

Gets the value.

@return the value

public String getValue()

{

return value;

}

public int compareTo(Item otherObject)

{

Item other = (Item) otherObject;

return key.compareTo(other.key);

}

LookupTable.java:

import java.util.ArrayList;

import java.util.Collections;

import java.util.Scanner;

/**

* Code for HW6

* @author

/**

A table for lookups and reverse lookups

public class LookupTable

{

private ArrayList<Item> byKey;

private ArrayList<Item> byValue;

/**

Constructs a LookupTable object.

public LookupTable()

{

byKey = new ArrayList<Item>();

byValue = new ArrayList<Item>();

}

/**

Reads key/value pairs.

@param in the scanner for reading the input

public void read(Scanner in)

{

. . .

}

/**

Looks up an item in the table.

@param k the key to find

@return the value with the given key, or null if no

such item was found.

public String lookup(String k)

{

. . .

}

/**

Looks up an item in the table.

@param v the value to find

@return the key with the given value, or null if no

such item was found.

public String reverseLookup(String v)

{

. . .

}

Explanation / Answer

* In this class we have 2 private lists byKey for looking by key (zipcode),

* and byValue for looking by city name.

* byKey has Items in the form Item(ZipCode,CityName) and byValue has Items in the form Item(CityName,Zipcode)

* We take input from the file and store them in lists as said above.

* The method lookup() uses byKey for binarysearching and

* the method reverselookup() uses byValue for binarySearching

* No changes have been made in the other 2 classes. You can use them directly.

Kindly rate the answer if you find it useful.*/

import java.util.ArrayList;

import java.util.Collections;

import java.util.Comparator;

import java.util.Scanner;

/**

* Code for HW6

* @author

/**

* A table for lookups and reverse lookups

public class LookupTable {

private ArrayList<Item> byKey;

private ArrayList<Item> byValue;

/**

* Constructs a LookupTable object.

public LookupTable() {

byKey = new ArrayList<Item>();

byValue = new ArrayList<Item>();

}

/**

* Reads key/value pairs.

* @param in

* the scanner for reading the input

public void read(Scanner in) {

int i = 0;

Item item;

String k = null, v = null;

while (in.hasNextLine()) {

if (i % 2 == 0)

k = in.nextLine();

else {

v = in.nextLine();

item = new Item(k, v);//Zipcode is key and city name is value

byKey.add(item);

item = new Item(v, k);//City name is key and zipcode is value

byValue.add(item);

}

i++;

}

//Sorting byKey list

Collections.sort(byKey, new Comparator<Item>() {

@Override

public int compare(Item o1, Item o2) {

// TODO Auto-generated method stub

return o1.getKey().compareTo(o2.getKey());

}

});

//Sorting byValue list

Collections.sort(byValue, new Comparator<Item>() {

@Override

public int compare(Item o1, Item o2) {

// TODO Auto-generated method stub

return o1.getKey().compareTo(o2.getKey());

}

});

}

/**

* Looks up an item in the table.

* @param k

* the key to find

* @return the value with the given key, or null if no such item was found.

public String lookup(String k) {

//Comparator to compare the keys

Comparator<Item> c = new Comparator<Item>() {

public int compare(Item u1, Item u2) {

return u1.compareTo(u2);

}

};

//Binary Search on the sorted list

int index = Collections.binarySearch(byKey, new Item(k, null), c);

if (index < 0)//If not found

return null;

Item item = byKey.get(index);

return item.getValue();//return the value

}

/**

* Looks up an item in the table.

* @param v

* the value to find

* @return the key with the given value, or null if no such item was found.

public String reverseLookup(String v) {

//Comparator to compare the keys

Comparator<Item> c = new Comparator<Item>() {

public int compare(Item u1, Item u2) {

return u1.compareTo(u2);

}

};

//Binary Search on the sorted list

int index = Collections.binarySearch(byValue, new Item(v, null), c);

if (index < 0)//If not found

return null;

Item item = byValue.get(index);

return item.getValue();//returning the value

}

Sample input: iazip.txt

50001

ACKWORTH

50002

ADAIR

RST

50003

ADEL

ABC

50005

ALBION

50006

ALDEN

50007

ALLEMAN

XYZ

Sample output:

Enter the name of the zipcode file:

iazip.txt