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CS1322/p3/TricksandTools.txt

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+This file contains a walkthrough on how to use important tools in Java.  These
+include Vectors, Enumerations and StringTokenizers.  All of these classes are
+located in the package java.util
+
+VECTORS
+===============================================================================
+In order to use the Vector class, you need to import java.util.Vector.
+Look in the Java API to see a list of all the methods that can be used with
+Vectors.  The great thing about Vectors is that they are dynamic like
+Linked Lists, but they give instantaneous access to elements like arrays.
+
+So lets say we had a small java class that utilized Vectors.  We want to add
+words when a person says them into the Vector - as long as the word is not in
+the Vector already.  When they are done speaking, we want to print out all of
+the words that they said.
+
+import java.util.Vector;
+
+public class SaveWords
+{
+	public SaveWords(){
+	       Vector v = new Vector();
+	       String word = "";
+	       while((word = WordISay()) != null) // as long as I say a word
+	       {
+			if(!(v.contains(word)))   // check to see if in Vector
+			{
+				//  if not add it
+				v.add(word)
+			}
+	       } // end while
+
+	       // loop through the vector (notice the size() method)
+	       for(int i = 0; i<v.size(); i++)
+	       {
+			// use v.elementAt to get a specific element without
+			// removing it.
+			System.out.println(v.elementAt(i));
+	       }
+
+	}
+}
+
+
+This is a simple walkthrough.  Other useful and important methods deal with
+removing an object and getting the index of an object.  Look in the API for
+these methods.  Check out the elements method as well.  This method returns
+an Enumeration of all the elements in the Vector (see below).
+
+
+ENUMERATION
+============================================================================
+
+The important methods for Enumeration are
+hasMoreElements and nextElement.
+
+hasMoreElements returns true if there are more elements while nextElement will
+return the next Object of the Enumeration.  Example of use...
+
+	Enumeration e.....
+
+	while(e.hasMoreElements()){
+
+	// do something with e.nextElement()
+	// remember that this is an Object and may need to be casted into the
+	// appropriate Object
+
+	} // end while
+
+
+STRING TOKENIZER
+=============================================================================
+
+The StringTokenizer class is very similar to the Enumeration class with respect
+to the methods that are able to be called.  The small difference is that the
+actual methods are called hasMoreTokens() and nextToken().  The nextToken method
+returns a String as opposed to an Object.  The StringTokenizer class does
+exactly what it says...it tokenizes (breaks up) a string.  The default delimiter
+is white space.  Thus if a StringTokenizer was declared as
+	StringTokenizer st = new StringTokenizer("How Are you doing?");
+
+then the code
+	while(st.hasMoreTokens()){
+		System.out.println(st.nextToken());
+	}
+
+would produce the following output
+	How
+	Are
+	you
+	doing?
+
+if instead the StringTokenizer was declared to delimit with respect to o's
+	StringTokenizer st = new StringTokenizer("How Are you doing?", "o");
+
+then the output would be...
+	H
+	w Are y
+	u d
+	ing?