In: Computer Science
IN JAVA
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 field 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 appropriate set and get methods. The body of the email message should be stored in the inherited variable text. Redefine the toString method to concatenate all text fields.
Similarly, define a class for File that is derived from Document and includes an 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 fields.
Finally, define a class DocumentTest that creates several sample objects of type Email and File in the main method. Test your 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 ContainsKeyword(Document docObject, String keyword) { if (docObject.toString().indexOf(keyword,0) >= 0) return true ; return false ;
Document.java:
public class Document {
private String text;
public Document(String text) {
this.text = text;
}
public String toString() {
return "text=" + text;
}
public String getText() {
return text;
}
public void setText(String text) {
this.text = text;
}
}
Email.java:
public class Email extends Document {
private String sender;
private String recipient;
private String title;
public Email(String text, String sender, String recipient, String title) {
super(text);
this.sender = sender;
this.recipient = recipient;
this.title = title;
}
public String getSender() {
return sender;
}
public void setSender(String sender) {
this.sender = sender;
}
public String getRecipient() {
return recipient;
}
public void setRecipient(String recipient) {
this.recipient = recipient;
}
public String getTitle() {
return title;
}
public void setTitle(String title) {
this.title = title;
}
@Override
public String toString() {
return "sender=" + sender + ", recipient=" + recipient + ", title=" + title + ", getText()=" + getText();
}
}
File.java:
public class File extends Document {
private String pathname;
public File(String text, String pathname) {
super(text);
this.pathname = pathname;
}
public String getPathname() {
return pathname;
}
public void setPathname(String pathname) {
this.pathname = pathname;
}
@Override
public String toString() {
return "pathname=" + pathname + ", getText()=" + getText();
}
}
DocumentTest.java:
public class DocumentTest {
public static void main(String[] args) {
Document doc1=new Email("Hi, How are you?","Alexander","Anderea","Greetings");
Document doc2=new File("abcdefghijklmnopqrstuvwxyz","D:/Documents/alphabet.txt");
System.out.println("My Email contains the keyword 'are' :" + containsKeyword(doc1,"are") );
System.out.println("My Email contains the keyword 'the' :" + containsKeyword(doc1,"the") );
System.out.println("My File contains the keyword 'abc' :" + containsKeyword(doc2,"abc") );
System.out.println("My Email contains the keyword 'cba' :" + containsKeyword(doc2,"cba") );
}
public static boolean containsKeyword(Document docObject, String keyword) {
if (docObject.toString().indexOf(keyword,0) >= 0)
return true ;
return false ;
}
}
Output of DocumentTest Class: