CS 596 Client-Server Programming
Classes: Containers

1. Containers
   1. The Container Problem
   2. Vector
   3. Enumeration
   4. Vectors and Enumeration
   5. Stack
   6. Hashtable
2. Some Useful Classes
   1. Random
   2. StringTokenizer
   3. BitSet
3. Object

template <class DataType>
class LinkedListNode
	{
	DataType	theData;
	LinkedListNode* link;

	// more code here
	}

class LinkedListNode
	{
	Object	theData;
	LinkedListNode link;
	}

class Student
	{
	String  name;
	}

class UseLinkedListNode 
	{
	public static void main( String args[] ) 
		{
		LinkedListNode  aNode  = new LinkedListNode();

		Student  junior  =  new Student();

		aNode.theData  =  junior;

		Student senior  =  (Student) aNode.theData;

		LinkedListNode  aNumNode  = new LinkedListNode();

		aNumNode.theData  =  5;  //compile error, 5 not an object

		}
	}

int, float, long, etc. are not object due to C/C++

Integer, Float, Double, Long are wrapper classes

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

		LinkedListNode  aNumNode  = new LinkedListNode();

		aNumNode.theData  = new Integer( 5 );

		int result  =  ((Integer) aNumNode.theData).intValue();

		}

import java.util.Vector;

class SampleVector 
{
	public static void main( String args[] ) 
	{
		Vector  growableList  =  new Vector( 2 );
		String  myName  =  "Roger";

		for ( int k = 0;  k < 5;  k++ )
			growableList.addElement(  new Integer( k )  );

		growableList.addElement(  myName   );
		growableList.addElement(  new SampleVector()  );

		growableList.setElementAt(  "Hi",  2  );
		System.out.println(  growableList.toString()  );

		String  convert  = (String) growableList.elementAt( 2 );

		growableList.removeElementAt(  5  );
		System.out.println(  growableList.indexOf(  myName  )  );
	}
}

-1

for (Enumeration e = v.elements() ; e.hasMoreElements() ;) 
	{
	System.out.println(e.nextElement());
	}

Returns true if the enumeration contains more elements; false if its empty.

Returns the next element of the enumeration.

import java.util.*;

class SampleVector 
{
	public static void main( String args[] ) 
	{
		Vector  monthyOutput  =  new Vector( 2 );
		Random  dailyOutput  =  new Random();

		for ( int k = 0;  k < 5;  k++ )
			monthyOutput.addElement(  
					new Integer(  dailyOutput.nextInt() ) );

		Enumeration  output  =  monthyOutput.elements();
		for (  ; output.hasMoreElements() ;  ) 
			System.out.print(  output.nextElement() + "\t" );
		System.out.println(   );

	output  =  monthyOutput.elements();
	int  totalOutput  =  0;
		for (  ; output.hasMoreElements() ;) 
		{
			Integer  storedOutput =  (Integer) output.nextElement();
			totalOutput  +=  storedOutput.intValue();
		}

		System.out.println(  totalOutput   );
	}
}

import  java.util.*;

class SampleStack 
	{
	public static void main( String args[] ) 
		{
		Stack  test  =  new  Stack();

		test.push( new Integer( 5 ) );
		test.push( 5 );		//compile error
		test.push( new Student() );

		System.out.println( test.pop() );

		Student  fromStack  = (Student) test.pop();
		}
	}

class Student
	{
	public  String name;
	}

empty() 
peek() 
pop() 
push(Object) 
search(Object) 

import  java.util.*;

class  Student {  String[]  courses;   }

class  SampleHash
	{
	public static void main( String args[] ) 
		{
		Student  csPerson  =  new  Student();
		Hashtable sample = new Hashtable();

		sample.put( "Roger", "Good Job" );
		sample.put( "Andrew", "Better Job" );
		sample.put( csPerson,  new Integer( 12 ) );

		Stack  ofCards  =  new  Stack();
		sample.put(  "Deck",  ofCards );

		String  myPerformance  = (String) sample.get( "Roger" );
		Enumeration  keys  =  sample.keys();

		while  ( keys.hasMoreElements()  )
			{
			System.out.print(  keys.nextElement()  +  "\t" );
			}
		System.out.println();

		Enumeration  elements  =  sample.elements();

		while  ( elements.hasMoreElements()  )
			{
			System.out.print(  elements.nextElement()  +  "\t" );
			}
		System.out.println();
		}
	}

import java.util.Random;

class  SampleRandom
	{
	public  static  void  main( String  args[]  )
		{
		Random  data   =  new Random();
		System.out.println(  data.nextDouble()  );
		System.out.println(  data.nextFloat()  );
		System.out.println(  data.nextGaussian()  );
		System.out.println(  data.nextLong()  );
		System.out.println(  data.nextDouble()  );
		}
	}

import java.util.*;
class  Parse
	{
	public  static  void  main( String  args[]  )
		{
		String  message  =  "this is a test";
		StringTokenizer  parser  =  new  StringTokenizer( message );
		
		System.out.println(  parser.countTokens()  ); 
		printTokens(  parser  );

		message  =  "Hi,Mom;this.is a funny, message";
		parser  =  new  StringTokenizer( message, ",;." );
		printTokens(  parser  );

		parser  =  new  StringTokenizer( message, ",;.", true );
		printTokens(  parser  );
		}

	static void printTokens(  StringTokenizer  input)
		{
		while (input.hasMoreTokens()) 
			{
			System.out.println(  input.nextToken()  );
			}
		}
	}

Constructs a StringTokenizer on the specified String, using the specified delimiter set. If boolean is true, return delimiters with tokens.

Constructs a StringTokenizer on the specified String, using the specified delimiter set.

Constructs a StringTokenizer on the specified String, using the default delimiter set (which is " \t\n\r").

Creates an empty set.

Creates an empty set with the specified size.

Creates a clone of the object.

Compares two Objects for equality.

Code to perform when this object is garbage collected.

Returns the Class of this Object.

Returns a hashcode for this Object.

Notifies a single waiting thread on a change in condition of another thread.

Notifies all of the threads waiting for a condition to change.

Returns a String that represents the value of this Object.

Causes a thread to wait until it is notified or the specified timeout expires.

More accurate wait.

Causes a thread to wait forever until it is notified.