import java.util.Random; /** * Models a playing die with sides numbered 1 to N. * All sides have uniform probablity of being rolled. * * @author Summer CS 307 class */ public class Die { public static final int DEFAULT_SIDES = 6; private static Random ourRandNumGen = new Random(); private final int iMyNumSides; private int iMyResult; /** * Default constructor.

* pre: none
* post: getNumSides() = DEFAULT_SIDES, getResult() = 1 */ public Die() { this(DEFAULT_SIDES); } /** * Create a Die with numSides sides

* pre: numSides > 1
* post: getNumSides() = numSides, getResult() = 1
* An exception will be generated if the preconditions are not met */ public Die(int numSides) { assert numSides > 1 : "Violation of precondition: numSides = " + numSides + "numSides must be greater than 1"; iMyNumSides = numSides; iMyResult = 1; assert getResult() == 1 && getNumSides() == numSides; } /** * Create a Die with numSides and top side and result set to result

* pre: numSides > 1, 1 <= result <= numSides
* post: getNumSides() = numSides, getResult() = 1
* An exception will be generated if the preconditions are not met */ public Die(int numSides, int result) { assert numSides > 1 && 1 <= result && result <= numSides : "Violation of precondition"; iMyNumSides = numSides; iMyResult = result; } /** * roll this Die. Every side has an equal chance of being the new result

* pre: none
* post: 1 <= getResult() <= getNumSides() * @return the result of the Die after the roll */ public int roll() { iMyResult = ourRandNumGen.nextInt(iMyNumSides) + 1; assert ( 1 <= getResult() ) && ( getResult() <= getNumSides() ); return iMyResult; } /** * return how many sides this Die has

* pre: none
* post: return how many sides this Die has * @return the number of sides on this Die */ public int getNumSides() { return iMyNumSides; } /** * get the current result or top number of this Die

* pre: none
* post: return the number on top of this Die * @return the current result of this Die */ public int getResult() { return iMyResult; } /** * returns true if this Die and the parameter otherObj are equal

* pre: none
* post: return true if the parameter is a Die object with the same number of sides as this Die and currently has the same result. * @return true if the the two Dice are equal, false otherwise */ public boolean equals(Object otherObj) { boolean result = true; if(otherObj == null) result = false; else if(this == otherObj) result = true; else if(this.getClass() != otherObj.getClass()) result = false; else { Die otherDie = (Die)otherObj; result = this.iMyResult == otherDie.iMyResult && this.iMyNumSides == otherDie.iMyNumSides; } return result; } /** * returns a String containing information about this Die

* pre: none
* post: return a String with information about the current state of this Die * @return: A String with the number of sides and current result of this Die */ public String toString() { return "Num sides " + getNumSides() + " result " + getResult(); } }// end of Die class

Die class. A class that models a playing die.