Reference no: EM13333460

Define a class named Document that contains an instance variable of type String named text that stores any textual content for the document. Create a method named toString that returns the text filed and also include a method to set this value. Next, define a class for Email that is derived from Document and includes instance variables for the sender, recipient, and title of an email message. Implement appropriateaccessor and mutator methods. The body of the email message should be stored in the inherited variable text. Redefine thetoString method to concatenate all text field.

Similarly, define a class for File that is derived from Document and includes a instance variable for the pathname. The textual contents of the file should be stored in the inherited variable text. Redefine the toString method to concatenate all text field.

Finally, create several sample objects of type Email and File in your main method. Test you objects by passing them to the following subroutine that returns true if the object contains the specified keyword in the text property.

public static Boolean ContainKeyword (Document docObject, String keyword)
{
if (docObject.toString().indexOf(keyword, 0) >= 0)
return true;
return false;
}