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?
Given the definition of the Country class:
public class country {
public enum Continent {ASIA, EUROPE}
String name;
Continent region;
public Country (String na, Continent reg) {
name = na, region = reg;
}
public String getName () {return name;}
public Continent getRegion () {return region;}
}
and the code fragment:
List couList = Arrays.asList (
new Country ("Japan", Country.Continent.ASIA),
new Country ("Italy", Country.Continent.EUROPE),
new Country ("Germany", Country.Continent.EUROPE));
Map> regionNames = couList.stream ()
.collect(Collectors.groupingBy (Country ::getRegion,
Collectors.mapping(Country::getName, Collectors.toList()))));
System.out.println(regionNames);
Given the code fragment:
Map books = new TreeMap<>();
books.put (1007, "A");
books.put (1002, "C");
books.put (1001, "B");
books.put (1003, "B");
System.out.println (books);
What is the result?
Given:
class Book {
int id;
String name;
public Book (int id, String name) {
this.id = id;
this.name = name;
}
public boolean equals (Object obj) { //line n1
boolean output = false;
Book b = (Book) obj;
if (this.name.equals(b name))}
output = true;
}
return output;
}
}
and the code fragment:
Book b1 = new Book (101, "Java Programing");
Book b2 = new Book (102, "Java Programing");
System.out.println (b1.equals(b2)); //line n2
Which statement is true?
Given the content of /resourses/Message.properties:
welcome1="Good day!"
and given the code fragment:
Properties prop = new Properties ();
FileInputStream fis = new FileInputStream ("/resources/Message.properties");
prop.load(fis);
System.out.println(prop.getProperty("welcome1"));
System.out.println(prop.getProperty("welcome2", "Test"));//line n1
System.out.println(prop.getProperty("welcome3"));
What is the result?
Given the code fragments:
class MyThread implements Runnable {
private static AtomicInteger count = new AtomicInteger (0);
public void run () {
int x = count.incrementAndGet();
System.out.print (x+" ");
}
}
and
Thread thread1 = new Thread(new MyThread());
Thread thread2 = new Thread(new MyThread());
Thread thread3 = new Thread(new MyThread());
Thread [] ta = {thread1, thread2, thread3};
for (int x= 0; x < 3; x++) {
ta[x].start();
}
Which statement is true?
Given the code fragment:
public static void main (String [ ] args) throws IOException {
BufferedReader br = new BufferedReader (new InputStremReader (System.in));
System.out.print ("Enter GDP: ");
//line 1
}
Which code fragment, when inserted at line 1, enables the code to read the GDP from the user?