Thread: Need help doing an exercise[constructors]

The exercise is:

In your examination folder, there is a file called Insurance.java. This class includes the following list of attributes:
name, age and insuranceTime. Modify this code by adding three constructors:
- the empty constructor where the class attributes are initialised as "no name" and 100 and "12 months";
- the constructor with three parameters: Insurance(String name, int age, String time), the order of the parameters
is important! Use these parameters to initialise the class attributes;
- the constructor with two parameters: Insurance(String name, int age), the insurance time should be set by default
to 12 months.
Add a print() method with a void return type that prints to the standard output the name, age and insurance time in
one line separated by space, such as: “no name 100 12 month”.
Note: you can test your solution by compiling and running the existing program InsuranceDemo.java in your
examination folder.

I did everything as told, but when compiling InsuranceDemo I get these errors:

./Insurance.java:26: error: class, interface, or enum expected
        System.out.println(name, age, time);
        ^
InsuranceDemo.java:7: error: cannot find symbol
		one.print();
		   ^
  symbol:   method print()
  location: variable one of type Insurance
InsuranceDemo.java:11: error: cannot find symbol
		two.print();
		   ^
  symbol:   method print()
  location: variable two of type Insurance
InsuranceDemo.java:15: error: cannot find symbol
		three.print();
		     ^
  symbol:   method print()
  location: variable three of type Insurance
4 errors

We're not supposed to touch InsuranceDemo.java in any way. So there must be something wrong with my code?

public class Insurance
{
	public String name;
	public int age;
	public String insuranceTime;
 
	public Insurance(){
            name = "no name";
            age= 100;
            insuranceTime= "12 months"; }
 
        public Insurance(String name, int age, String time){
            name=name;
            age=age;
            time=insuranceTime;
        }
        public Insurance(String name, int age){
            name=name;
            age=age;
 
 
        }   
        System.out.println(name, age, time);
}

This is the InsuranceDemo.java code that we're not supposted to touch, just in case itself might have some errors:

public class InsuranceDemo
{
	public static void main(String args[])
	{
		System.out.println("Creating and printing object using parameterless constructor");
		Insurance one = new Insurance();
		one.print();
 
		System.out.println("Creating and printing object using three parameter constructor");
		Insurance two = new Insurance("John Smith", 45, "6 months");
		two.print();
 
		System.out.println("Creating and printing object using two parameter constructor");
		Insurance three = new Insurance("Jane Smith", 40);
		three.print();
	}
}

the problem is where your system.out.println statement lies in your first code.

the question instructs for there to be a method of void type called print. You should replace that print statement with the print method that prints the requested data.

I.E

public void print(){
//desired print output
}

Furthermore, you can look into the provided test class and note that objects are calling a .print() method.
one-three.print();

In Java, executable statements other than declaration/initializations and initialization blocks must be inside methods.

Originally Posted by GStateSwish

the problem is where your system.out.println statement lies in your first code.

the question instructs for there to be a method of void type called print. You should replace that print statement with the print method that prints the requested data.

I.E

public void print(){
//desired print output
}

Furthermore, you can look into the provided test class and note that objects are calling a .print() method.
one-three.print();

Thanks for the speedy response! At least in runs now. Code now looks like this:

public class Insurance
{
	public String name;
	public int age;
	public String insuranceTime;
 
	public Insurance(){
            name = "no name";
            age= 100;
            insuranceTime= "12 months"; }
 
        public Insurance(String name, int age, String time){
            name=name;
            age=age;
            time=insuranceTime;
        }
        public Insurance(String name, int age){
            name=name;
            age=age;
 
 
        }   
   public void print(){
       System.out.print(name,age,time);
}     
}

The output is way off. What I'm supposed to get:

Creating and printing object using parameterless constructor
no name 100 12 months
Creating and printing object using three parameter constructor
John Smith 45 6 months
Creating and printing object using two parameter constructor
Jane Smith 40 12 months

What I'm getting is:

Creating and printing object using parameterless constructor
no nameCreating and printing object using three parameter constructor
nullCreating and printing object using two parameter constructor
null

For starters, it's not recognizing the other two variables.

First, inside of your constructors, declare your variables appropriately
i.e

public Insurance (String name .. etc){
this.name = name;
}

the way the class will determine which name to use. Should do it this way if your parameter and data field are exact.

error at your print statement. if you are going to do it like that, separate the data with string spaces.

System.out.println(name +" " +age " "+time)


you could also implement accessor methods for the fields.


you also have output format errors. Remember that the print statement sends output.
search for how to format that on seperate lines using \n.

I don't think it's based on how I write the System.out.println statement? I corrected it to the way you wrote it and it still gives the same output.

I could try to add accecors, but it didn't ask for it in the question so the results should display normally just with a System.out.println method.

EDIT:

I know I need to fix the formatting, but I need to get the actual answer right first. It's still giving me null

The main problem is the variables assigning to themselves.. forgot to mention that the first time.

fix the variable assignments.

in your second constructor you are also doing something weird

that should be
insuranceTime = time; not the other way around.

Then in your print statement, you should be referencing insuranceTime, not time, if you are going to be using your data fields over accessor methods. good luck

Should I create new variables for each constructor then?

Name= name;
Age= age;

etc. ?

I've tried doing this.name and this.age and it didn't change a thing.

System.out.print()
vs
System.out.println()

public class  Insurance
{
	public String name;
	public int age;
	public String insuranceTime;
 
	public Insurance(){
            name = "no name";
            age= 100;
            insuranceTime= "12 months"; }
 
        public Insurance(String name, int age, String time){
            this.name=name;
            this.age=age;
            insuranceTime = time;
        }
        public Insurance(String name, int age){
            this.name=name;
            this.age=age;
            this.insuranceTime = "12 months";
 
 
        }   
   public void print(){
       System.out.println(name+" "+age+" "+insuranceTime);

Just needed to add a few } and your solution worked. I guess I'll have to research .this

Thanks for putting up with me GState