java/DataLabs/lab2/ArrayBagDemo.java
2025-03-11 17:24:33 +03:00

242 lines
7.6 KiB
Java

/** A demonstration of the class ArrayBag
@author Frank M. Carrano
@version 4.0
*/
public class ArrayBagDemo
{
public static void main(String[] args)
{
String[] contentsOfBag = {"A", "A", "B", "A", "C", "A"};
// Tests on an empty bag
BagInterface<String> aBag = new ArrayBag<>(contentsOfBag.length);
System.out.println("Testing an initially empty bag:");
testIsEmpty(aBag, true);
String[] testStrings1 = {"", "B"};
testFrequency(aBag, testStrings1);
testContains(aBag, testStrings1);
testRemove(aBag, testStrings1);
// Adding strings
System.out.println("Adding " + contentsOfBag.length +
" strings to an initially empty bag with" +
" the capacity to hold more than " +
contentsOfBag.length + " strings:");
testAdd(aBag, contentsOfBag);
// Tests on a bag that is not empty
testIsEmpty(aBag, false);
String[] testStrings2 = {"A", "B", "C", "D", "Z"};
testFrequency(aBag, testStrings2);
testContains(aBag, testStrings2);
// Removing strings
String[] testStrings3 = {"", "B", "A", "C", "Z"};
testRemove(aBag, testStrings3);
System.out.println("\nClearing the bag:");
aBag.clear();
testIsEmpty(aBag, true);
displayBag(aBag);
// Filling an initially empty bag to capacity
System.out.println("\nTesting an initially empty bag that " +
" will be filled to capacity:");
aBag = new ArrayBag<String>(7);
String[] contentsOfBag2 = {"A", "B", "A", "C", "B", "C", "D"};
testAdd(aBag, contentsOfBag2);
System.out.println("Try to add another string to the full bag:");
if (aBag.add("another string"))
System.out.println("Added a string beyond the bag's capacity: ERROR!");
else
System.out.println("The method add cannot add another string: OK");
} // end main
// Tests the method add.
private static void testAdd(BagInterface<String> aBag, String[] content)
{
System.out.print("Adding ");
for (int index = 0; index < content.length; index++)
{
aBag.add(content[index]);
System.out.print(content[index] + " ");
} // end for
System.out.println();
displayBag(aBag);
} // end testAdd
// Tests the two remove methods.
private static void testRemove(BagInterface<String> aBag, String[] tests)
{
for (int index = 0; index < tests.length; index++)
{
String aString = tests[index];
if (aString.equals("") || (aString == null))
{
// test remove()
System.out.println("\nRemoving a string from the bag:");
String removedString = aBag.remove();
System.out.println("remove() returns " + removedString);
}
else
{
// test remove(aString)
System.out.println("\nRemoving \"" + aString + "\" from the bag:");
boolean result = aBag.remove(aString);
System.out.println("remove(\"" + aString + "\") returns " + result);
} // end if
displayBag(aBag);
} // end for
} // end testRemove
// Tests the method isEmpty.
// correctResult indicates what isEmpty should return.
private static void testIsEmpty(BagInterface<String> aBag, boolean correctResult)
{
System.out.print("Testing isEmpty with ");
if (correctResult)
System.out.println("an empty bag:");
else
System.out.println("a bag that is not empty:");
System.out.print("isEmpty finds the bag ");
if (correctResult && aBag.isEmpty())
System.out.println("empty: OK.");
else if (correctResult)
System.out.println("not empty, but it is empty: ERROR.");
else if (!correctResult && aBag.isEmpty())
System.out.println("empty, but it is not empty: ERROR.");
else
System.out.println("not empty: OK.");
System.out.println();
} // end testIsEmpty
// Tests the method getFrequencyOf.
private static void testFrequency(BagInterface<String> aBag, String[] tests)
{
System.out.println("\nTesting the method getFrequencyOf:");
for (int index = 0; index < tests.length; index++)
{
String aString = tests[index];
if (!aString.equals("") && (aString != null))
{
System.out.println("In this bag, the count of " + tests[index] +
" is " + aBag.getFrequencyOf(tests[index]));
} // end if
} // end for
} // end testFrequency
// Tests the method contains.
private static void testContains(BagInterface<String> aBag, String[] tests)
{
System.out.println("\nTesting the method contains:");
for (int index = 0; index < tests.length; index++)
{
String aString = tests[index];
if (!aString.equals("") && (aString != null))
{
System.out.println("Does this bag contain " + tests[index] +
"? " + aBag.contains(tests[index]));
} // end if
} // end for
} // end testContains
// Tests the method toArray while displaying the bag.
private static void displayBag(BagInterface<String> aBag)
{
System.out.println("The bag contains " + aBag.getCurrentSize() +
" string(s), as follows:");
Object[] bagArray = aBag.toArray();
for (int index = 0; index < bagArray.length; index++)
{
System.out.print(bagArray[index] + " ");
} // end for
System.out.println();
} // end displayBag
} // end ArrayBagDemo
/*
Testing an initially empty bag:
Testing isEmpty with an empty bag:
isEmpty finds the bag empty: OK.
Testing the method getFrequencyOf:
In this bag, the count of B is 0
Testing the method contains:
Does this bag contain B? false
Removing a string from the bag:
remove() returns null
The bag contains 0 string(s), as follows:
Removing "B" from the bag:
remove("B") returns false
The bag contains 0 string(s), as follows:
Adding 6 strings to an initially empty bag with the capacity to hold more than 6 strings:
Adding A A B A C A
The bag contains 6 string(s), as follows:
A A B A C A
Testing isEmpty with a bag that is not empty:
isEmpty finds the bag not empty: OK.
Testing the method getFrequencyOf:
In this bag, the count of A is 4
In this bag, the count of B is 1
In this bag, the count of C is 1
In this bag, the count of D is 0
In this bag, the count of Z is 0
Testing the method contains:
Does this bag contain A? true
Does this bag contain B? true
Does this bag contain C? true
Does this bag contain D? false
Does this bag contain Z? false
Removing a string from the bag:
remove() returns A
The bag contains 5 string(s), as follows:
A A B A C
Removing "B" from the bag:
remove("B") returns true
The bag contains 4 string(s), as follows:
A A C A
Removing "A" from the bag:
remove("A") returns true
The bag contains 3 string(s), as follows:
A A C
Removing "C" from the bag:
remove("C") returns true
The bag contains 2 string(s), as follows:
A A
Removing "Z" from the bag:
remove("Z") returns false
The bag contains 2 string(s), as follows:
A A
Clearing the bag:
Testing isEmpty with an empty bag:
isEmpty finds the bag empty: OK.
The bag contains 0 string(s), as follows:
Testing an initially empty bag that will be filled to capacity:
Adding A B A C B C D
The bag contains 7 string(s), as follows:
A B A C B C D
Try to add another string to the full bag:
The method add cannot add another string: OK
*/
/*
Exception in thread "main" java.lang.SecurityException: Attempt to create a bag whose capacity exceeds 3
at ArrayBag.<init>(ArrayBag.java:38)
at ArrayBagDemo.main(ArrayBagDemo.java:12)
*/