String car;
if (type == 'E')
{fee = rate*50;
car = "Economy";}
else if (type == 'M')
{fee = rate*70;
car = "Midsize";}
else if (type == 'F')
{fee = rate*100;
car = "Fullsize";}
System.out.println("Car type is " + car);
This is the part of my program that i have problem with. I get 'local variable car may not have been initialized ' . What should i do to make 'car' initialized ?
Java can't guarantee that car will ever become initialized. You don't have a guaranteed case (else) in your if statement that assigns car.
Initialize it to some value, such as an empty string.
String car = "";
In general, you set your String to null to solve the compilation error.
String car = null;
That is because Java is trying to protect you from doing something you don't expect. If all the if statements are not executed, the variable will not get assigned. To tell Java, that you know that this might happen, you just chose explicitly to set it to null.
Java can't tell what's going to happen with your variable reach print, as it's initially pointing nowhere and further initializations are enclosed in conditionals Set your car variable to a default value depending on logic: "" or null are good options but it's really up to you in the end
I would consider to do this another way:
switch (type) {
case 'E':
fee =rate* 50;
car = "Economy";
break;
case 'M':
fee =rate* 70;
car = "Economy";
break;
case 'F':
fee =rate*100;
car = "Economy";
break;
default:
fee = 0;
car = "";
}
How I would of solved this problem using an inner Enum class.
public class EnumExample {
public enum CarType {
E( 50,"Economy" ),
F( 70, "Midsize" ),
M( 100, "Fullsize");
// Add as many as you want
private int cost;
private String type;
CarType(int theCost, String theType) {
cost = theCost;
type = theType;
}
public int getFee(int rate) {
return rate*cost;
}
public String toString() {
return type;
}
}
public static void main( String[] args ) {
String type = "E";
int rate = 25;
switch( CarType.valueOf( type ) ) {
case E:
System.out.println( "The Car Type is: " + CarType.E );
System.out.println( "The fee is: " + CarType.E.getFee(rate) );
break;
case F:
System.out.println( "The Car Type is: " + CarType.F );
System.out.println( "The fee is: " + CarType.F.getFee(rate) );
break;
case M:
// ETC
default:
// Use a switch/case so you can add 'no car type' e.g Fee = 0;
}
}
}
E,MorF? Just initialize it withString car = "";enumfor yourE,M, andFvalues; you can assign names, descriptions, rates, and so on to the enum values, and it makes your code cleaner, safer, and more maintainable.