Chap 6


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public class AllInMain { public static void main(String args[]) { double score = Math.random()*100; if (score >= 80) { System.out.println("Grade is A");
} else if (score >= 70) {
System.out.println("Grade is B"); } else if (score >= 60){
System.out.println("Grade is C"); } else if (score >= 50){
System.out.println("Grade is D"); } else {
System.out.println("Grade is F"); }
}
}



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class NumericalClass { public public void calculate() {
double score = Math.random()*100;
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} else if (score >= 70) { System.out.println("Grade is B");
} else if (score >= 60){ System.out.println("Grade is C");
} else if (score >= 50){ System.out.println("Grade is D");
} else { System.out.println("Grade is F");
} }
}
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public static void main(String args[]) {
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class NumericalClassV1 { public void calculate() {
public double score = Math.random()*100; if (score >= 80) {
System.out.println("Grade is A"); } else if (score >= 70) {
System.out.println("Grade is B");
} else if (score >= 60){ System.out.println("Grade is C");
} else if (score >= 50){ System.out.println("Grade is D");
} else { System.out.println("Grade is F");
}
} public static void main(String args[]) {
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} }



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} else if (score >= 60){ System.out.println("Grade is C");
} else if (score >= 50){ System.out.println("Grade is D");
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public void callMethod() {
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public void printInfo(Student s) {
if (s instanceof PhDStudent) {


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} else if (s instanceof GradStudent) {


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} else if (s instanceof FullTimeStudent) {


System.out.println("Full-Time Student");
} else if (s instanceof PartTimeStudent) {


System.out.println("Part-Time Student");

} else if (s instanceof Student) {


System.out.println("Student");

} }

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public class Student { protected String id;
protected String name; protected double gpa; public String getID() { return id; } public String getName() { return name; } public double getGPA() { return gpa; } } public class GradStudent extends Student { private String thesisTitle; private String supervisor; public String getThesisTitle() { return thesisTitle; } public String getSupervisor() { return supervisor; } } public class TestCallingMethods { 



public static void main(String args[]) { Student s1 = new GradStudent(); s1.getSupervisor(); // compile error Student s2 = new Student(); ((GradStudent) s2).getSupervisor(); // runtime error

}


}


  

 
  









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