Java Reference
In-Depth Information
Display 4.16
A Class for Pet Records
(part 1 of 4)
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public
String toString()
11
{
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return ("Name: " + name + " Age: " + age + " years"
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+ "\nWeight: " + weight + " pounds");
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}
15
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public
Pet(String initialName,
int
initialAge,
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double
initialWeight)
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{
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name = initialName;
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if
((initialAge < 0) || (initialWeight < 0))
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{
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System.out.println("Error: Negative age or weight.");
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System.exit(0);
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}
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else
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{
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age = initialAge;
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weight = initialWeight;
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}
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}
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public void
set(String newName,
int
newAge,
double
newWeight)
Constructors are only called when you create
an object, such as with
new
. To change an
already existing object, you use one or more
methods like these
set
methods.
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{
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name = newName;
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if
((newAge < 0) || (newWeight < 0))
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{
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System.out.println("Error: Negative age or weight.");
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System.exit(0);
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}
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else
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{
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age = newAge;
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weight = newWeight;
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}
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}
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public
Pet(String initialName)
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{
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name = initialName;
Constructors normally set all instance
variables, even if there is not a full set of
parameters.
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age = 0;
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weight = 0;
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}
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public void
setName(String newName)
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{
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name = newName;
Age and weight are unchanged.
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}
(continued)
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