Most Recent Oracle 1Z0-809 Exam Dumps

Which two are elements of a singleton class? (Choose two.)

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Given the code fragment:

public void recDelete (String dirName) throws IOException {

File [ ] listOfFiles = new File (dirName) .listFiles();

if (listOfFiles ! = null && listOfFiles.length >0) {

for (File aFile : listOfFiles) {

if (aFile.isDirectory ()) {

recDelete (aFile.getAbsolutePath ());

} else {

if (aFile.getName ().endsWith (''.class''))

aFile.delete ();

}

}

}

}

Assume that Projects contains subdirectories that contain .class files and is passed as an argument to the recDelete () method when it is invoked.

What is the result?

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Given the code fragments:

public class Book implements Comparator {

String name;

double price;

public Book () {}

public Book(String name, double price) {

this.name = name;

this.price = price;

}

public int compare(Book b1, Book b2) {

return b1.name.compareTo(b2.name);

}

public String toString() {

return name + '':'' + price;

}

}

and

Listbooks = Arrays.asList (new Book (''Beginning with Java'', 2), new book (''A

Guide to Java Tour'', 3));

Collections.sort(books, new Book());

System.out.print(books);

What is the result?

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Given the code fragments:

and

What is the result?

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Given the code fragment:

Which code fragment, when inserted at line n1, ensures false is printed?

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