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Sun Dec 02 17:35:00 CST 2012
Instantiate a Date object with the noarg constructor
This program instantiates an object of the Date class using the constructor that takes no parameters.
Call the overridden toString method
Then it calls the overridden toString method to populate a String object that represents the Date object.
Following this, it displays that String object by calling the print method, producing the first part of the output shown above. (The actual date and time will vary depending on when the program is executed.)
Get the time property value
Then it calls the getTime method to get and display the value of the time property.
This is a representation of the same date and time shown above , but in milliseconds:
1354491300781
D. Joe Age = 35 Weight = 162.5
Upgraded program from Question 8
The program used for this question is an upgrade to the program that was used for Question 8 .
Dummy class overrides the toString method
In particular, in this program, the class named Dummy overrides the toString method in such a way as to return a String representing the object that would be useful to a human observer.
The String that is returned contains the values of the instance variables of the object: name, age, and weight.
Overridden toString method code
The overridden toString method for the Dummy class is shown below for easy reference.
Overridden
toString method
public String toString(){
String x = name + " " +" Age = " + age + " " +
" Weight = " + weight;return x;
}//end toString() |
The code in the overridden toString method is almost trivial.
The important thing is not the specific code in a specific overridden version of the toString method.
Why override the toString method?
Rather, the important thing is to understand why you should probably overridethe toString method in most of the new classes that you define.
In fact, you should override the toString method in all new classes that you define if a String representation of an instance of that class will ever be needed for any purpose.
The code will vary
The code required to override the toString method will vary from one class to another. The important point is that the code must return areference to a String object. The String object should encapsulate information that represents the original object in aformat that is meaningful to a human observer.
C. Dummy@273d3c
Display an object of the Dummy class
This program instantiates a new object of the Dummy class, and passes that object's reference to the method named println .
The purpose of the println method is to display a representation of the new object that is meaningful to a human observer. Inorder to do so, it requires a String representation of the object.
The toString method
The class named Object defines a default version of a method named toString .
All classes inherit the toString method.
A child of the Object class
Those classes that extend directly from the class named Object inherit the default version of the toString method.
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