31. Which of these methods deletes all the elements from invoking collection?
32. What does Collections.emptySet() return?
33. What will be the output of the following Java code?
import java.util.*;
class Bitset
{
public static void main(String args[])
{
BitSet obj = new BitSet(5);
for (int i = 0; i < 5; ++i)
obj.set(i);
obj.clear(2);
System.out.print(obj);
}
}
import java.util.*;
class Bitset
{
public static void main(String args[])
{
BitSet obj = new BitSet(5);
for (int i = 0; i < 5; ++i)
obj.set(i);
obj.clear(2);
System.out.print(obj);
}
}34. What will be the output of the following Java code snippet?
public class Demo
{
public static void main(String[] args)
{
Map sampleMap = new TreeMap();
sampleMap.put(1, null);
sampleMap.put(5, null);
sampleMap.put(3, null);
sampleMap.put(2, null);
sampleMap.put(4, null);
System.out.println(sampleMap);
}
}
public class Demo
{
public static void main(String[] args)
{
Map sampleMap = new TreeMap();
sampleMap.put(1, null);
sampleMap.put(5, null);
sampleMap.put(3, null);
sampleMap.put(2, null);
sampleMap.put(4, null);
System.out.println(sampleMap);
}
} 35. What will be the output of the following Java code?
import java.util.*;
class vector
{
public static void main(String args[])
{
Vector obj = new Vector(4,2);
obj.addElement(new Integer(3));
obj.addElement(new Integer(2));
obj.addElement(new Integer(5));
System.out.println(obj.capacity());
}
}
import java.util.*;
class vector
{
public static void main(String args[])
{
Vector obj = new Vector(4,2);
obj.addElement(new Integer(3));
obj.addElement(new Integer(2));
obj.addElement(new Integer(5));
System.out.println(obj.capacity());
}
}36. Which of these object stores association between keys and values?
37. What will be the output of the following Java program?
import java.util.*;
class Collection_iterators
{
public static void main(String args[])
{
LinkedList list = new LinkedList();
list.add(new Integer(2));
list.add(new Integer(8));
list.add(new Integer(5));
list.add(new Integer(1));
Iterator i = list.iterator();
Collections.reverse(list);
while(i.hasNext())
System.out.print(i.next() + " ");
}
}
import java.util.*;
class Collection_iterators
{
public static void main(String args[])
{
LinkedList list = new LinkedList();
list.add(new Integer(2));
list.add(new Integer(8));
list.add(new Integer(5));
list.add(new Integer(1));
Iterator i = list.iterator();
Collections.reverse(list);
while(i.hasNext())
System.out.print(i.next() + " ");
}
}38. Which of these methods can be used to search an element in a list?
39. How can we remove an object from ArrayList?
40. What will be the output of the following Java program?
import java.util.*;
class Output
{
public static void main(String args[])
{
ArrayList obj = new ArrayList();
obj.add("A");
obj.ensureCapacity(3);
System.out.println(obj.size());
}
}
import java.util.*;
class Output
{
public static void main(String args[])
{
ArrayList obj = new ArrayList();
obj.add("A");
obj.ensureCapacity(3);
System.out.println(obj.size());
}
}Read More Section(Collections Framework in java)
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