Solutions to Self-Study Exercises

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Solution 3.1	A method declaration defines the method by specifying its name, qualifiers, return type, formal parameters, and algorithm, thereby associating a name with a segment of executable code. A method invocation calls or uses a defined method.
Solution 3.2	A formal parameter is a variable in the method declaration. Its purpose is to store a value while the method is running. An argument is a value passed to a method in place of a formal parameter.
Solution 3.3	The following code declares two instance variables for names of players and defines a setName() method: private String nameOne = "Player One"; private String nameTwo = "Player Two"; public void setNames(String name1, String name2) { nameOne = name1; nameTwo = name2; } Of course, there are many other appropriate names for the variables and parameters and other initial assignments.
Solution 3.4	A method call that sets the names of the players of game1 is: game1.setNames("Xena","Yogi");

Solution 3.5	A constructor cannot have a return type, such as void.
Solution 3.6	One definition for the method is: public OneRowNim(int sticks) { nSticks = sticks; player = 2; }

Solution 3.7	The following would be displayed on the screen: 1 20 false
Solution 3.8	One definition for the method is: public int getMoves() { return nMoves; }
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Solution 3.9	One definition for the method is: public boolean playerOneIsNext() { return (player == 1); }

Solution 3.10	See Figure 3.21. Figure 3.21. Flowchart of the if-else version of the getStatus() method.
Solution 3.11	if (isHeavy == true) System.out.println("Heavy") ; else; // Error (remove this semicolon) System.out.println("Light"); if (isLong == true) System.out.println("Long") else // Error (end line above with semicolon) System.out.println("Short");
Solution 3.12	public String getPlayerName() { if (player == 1) return "Ann"; else if (player == 2) return "Bill"; else if (player == 3) return "Cal"; else return "Error"; }
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Solution 3.13	When passing an argument for a primitive type, a copy of the argument's value is passed. The actual argument cannot be changed inside the method. When passing a reference to an object, the object can be changed within the method.

Solution 3.14

public int sumCubes(int min, int max) {     int num = min;     int sum = 0;     while (num <=  max) {          // While num <= max         sum = sum + num*num*num;   // Add cube of num to sum         num = num + 1;             // Add 1 to num     }                              // while     return sum;                    // Return the sum }