1 /* Demo for: Classes
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Student.java
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This class defines a simple template for student objects */
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5 public class Student
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//***** Static Variable *****//
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static int studentCount;
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//***** Instance Variables *****//
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private String untId;
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private String name;
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private char gender;
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private float gpa;
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// ***** Constructor *****//
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// It doesn't make sense to accept the default initial
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// values for these instance variables because each student
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// would have the name "null", ID "null" and is of the ' '
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// gender. Therefore, a non-default constructor method is
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// created below, instead of using the default constructor
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// that Java runs implicitly for classes without an explicitly
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// created constructor method.
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public Student(String i, String n, char g, float gpa)
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{
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untId = i;
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name = n;
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gender = g;
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this.gpa = gpa;
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}
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// Like regular methods, a constructor method can be overloaded.
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// If warranted by software specs, we can create multiple version of the
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// constructor method. Below, we create a version that emulates the
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// "default" or implicit constructor that Java will run if no construtor
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// method is defined. (As an aside, if a constructor is created, Java will
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// assume that we want to be control and will not run the "default"
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// constructor any more.)
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public Student()
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{
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}
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// Another version of the constructor. This version only initializes the ID
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// and name. A realistic business scenario may be that some demographic data
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// of the customers are optional. So it may be that the only mandatory fields
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// of input are ID and name. In this case, we only initialize ID and name.
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public Student(String i, String n)
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{
untId = i;
name = n;
}
// ***** Setters and Getters *****//
// For UNT ID //
public void setUNTID(String id)
{
untId = id;
}
public String getUNTID()
{
return untId;
}
// For Name //
public void setName(String name)
{
this.name = name;
}
public String getName()
{
return name;
}
// For Gender //
public void setGender(char gender)
{
this.gender = gender;
}
public char getGender()
{
return gender;
}
// For Age //
public void setGPA(float gpa)
{
this.gpa = gpa;
}
public float getGPA()
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{
return gpa;
}
// ***** Static Methods *****//
static void addToCount()
{
studentCount++;
}
static int readStudentCount()
{
return studentCount;
}
// ***** Instance Method *****//
public void retrieveInfo()
{
String msg = "================================\n";
msg += "Generated in Student Class\n";
msg += untId + "\t" + name + "\t" + gpa + "\n";
msg += "================================";
System.out.println(msg);
}
E:/BCIS 3680/05-classes/Student.java
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