Answer / geeta

StringBuffer

Answer / sitaram

string buffer and string builder classes are used to
concatenate the two or more strings in a loop.

Answer / narasimha

we any use the both classes String and StringBuffer.
but if we use StringBuffer it would be advatagebecase we
are going to create only one Object.if we use the String
class it is going to create the one for each itration.now
it up to you which one to use

How do you decide when to use arraylist and linkedlist?

0 Answers  

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What is the concatenation operator in java?

0 Answers   Aspire, Infogain,

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What a static class can contains?

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how its run?

0 Answers  

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Question 7 [8] Consider the following class and answer the questions below it: public class StackWithGuard extends Stack { public StackWithGuard(int size) { super(size); } synchronized public boolean isEmpty() { return super.isEmpty(); } synchronized public boolean isFull() { return super.isFull(); } synchronized public int getSize() { return super.getSize(); } synchronized public void push(Object obj) { try { while (isFull()) { wait(); } } catch (InterruptedException e) {} super.push(obj); COS2144/102 11 notify(); } synchronized public Object pop() { try { while (isEmpty()) { wait(); } } catch (InterruptedException e) {} Object result = super.pop(); notify(); return result; } public static void main(String args[]) { StackWithGuard stack = new StackWithGuard(5); new Producer(stack, 15).start(); new Consumer(stack, 15).start(); } } Note: The Stack class is provided in the Appendix. Note also: The following questions all refer to the pop() method of the StackWithGuard class given above. 7.1 What does the synchronized keyword ensure for this method? (2) 7.2 Why is a while loop used to test whether the stack is empty? In other words, why wouldn't the following if statement be sufficient? if (isEmpty()) { wait(); } (2) 7.3 Why is the result of popping (provided by the inherited pop() method) stored in a temporary variable? In other words, why wouldn't the following statement be sufficient? return super.pop(); (2) 7.4 Why is the while loop placed in a try-catch structure? (2) Appendix The LinkedQueue class: public class LinkedQueue implements Queue { private Node first, last; private int count; public LinkedQueue() { first = last = null; count =0; } public int size() { return count; } public boolean isEmpty() { return (count == 0); 12 } public void enqueue(Object o) { Node node = new Node(); node.element = o; node.next = null; node.prev = last; if (last != null){ last.next = node; } else { last = first = node; } last = node; count++; } public void dequeue() { if ((first!= null) & (first.next!=null)) { first = first.next; first.prev = null; count--; } else { first = last = null; count--; } } public Object front() { return first; } } class Node { Object element; Node next, prev; } The Stack class: public class Stack { protected Object rep[]; protected int top = -1; protected int size = 0; protected int count = 0; public Stack(int size) { if (size > 0) { this.size = size; rep = new Object[size]; } } public boolean isFull() { return (count == size); } public boolean isEmpty() { return (count == 0); } public int getSize() { return size; } public void push(Object e) { if (e != null && !isFull()) { COS2144/102 13 top++; rep[top] = e; count ++; } } public Object pop() { Object result = null; if (!isEmpty()) { result = rep[top]; top--; count--; } return result; } }

0 Answers  

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How many types of packages are there in Java?

5 Answers  

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Relationship between an event-listener interface and an event-adapter class?

1 Answers  

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What is substring in java?

0 Answers  

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What does those terms actually mean included in the j.d.k i.6?

0 Answers  

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public class BatchTest { public static void main(String[] args) { Runtime run = Runtime.getRuntime(); try { Process p = run.exec("cmd start /c D:/test.bat"); System.out.println(p.exitValue()); } catch (Exception e) { e.printStackTrace(); } System.out.println("FINISHED"); } }

0 Answers  

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What is a control variable example?

0 Answers  

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write a program to create an arraylist and listeterator.and value should be enter through keyboard.

1 Answers   Axcend,

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