Answer / muralisankar

Both are to navigate collection objects. But Enumerator you
can not manipulate where as in Iterator you can add and
remove objects.

Answer / siva thimmannagari

Iterator supports only hasNext(),
next() and remove() methods.
It is not synchronized.


Enumeration supports ONLY
hasMoreElements(), nextElement().
It is synchronized.

Answer / aslam

Iterator has an additional method remove() and also
iterator checks for the concurrent modifications which will
be useful in multi threaded applications.

while Enumerator is much faster for sequential
access over collection elements, because it doesnot have
the additional overhead of checking concurrent modifications

Answer / raju

From my experiance shows Enumeration is thread safe ..

What is meant by stack and queue?

0 Answers   GrapeCity,

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What is a generic type?

0 Answers  

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Why do we need main method to execute a java program?

1 Answers   Virtusa,

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Question 5 [15] Consider the following classes, illustrating the Strategy design pattern: import java.awt.*; abstract class Text { protected TextApplet tA; protected Text(TextApplet tApplet) { tA = tApplet; } abstract public void draw(Graphics g); } class PlainText extends Text { protected PlainText(TextApplet tApplet) { super(tApplet); } public void draw(Graphics g) { g.setColor(tA.getColor()); g.setFont(new Font("Sans-serif", Font.PLAIN, 12)); g.drawString(tA.getText(), 20, 20); } } class CodeText extends Text { protected CodeText(TextApplet tApplet) { super(tApplet); } public void draw(Graphics g) { g.setColor(tA.getColor()); g.setFont(new Font("Monospaced", Font.PLAIN, 12)); g.drawString(tA.getText(), 20, 20); } } public class TextApplet extends java.applet.Applet { protected Text text; protected String textVal; protected Color color; public String getText() { return textVal; } public Color getColor() { return color; } public void init() { textVal = getParameter("text"); String textStyle = getParameter("style"); String textColor = getParameter("color"); if (textStyle == "code") text = new CodeText(this); else text = new PlainText(this); if (textColor == "red") color = Color.RED; else if (textColor == "blue") color = Color.BLUE; else color = Color.BLACK; } public void paint(Graphics g) { text.draw(g); 10 } } The Text class is more complicated than it should be (there is too much coupling between the Text and TextApplet classes). By getting rid of the reference to a TextApplet object in the Text class and setting the colour in the paint() method, one could turn the Text class into an interface and simplify the strategy classes considerably. 5.1 Rewrite the Text and PlainText classes to do what is described above. (6) 5.2 Explain the consequent changes that are necessary to the TextApplet class. (4) 5.3 Write an additional strategy class called FancyText (to go with your simplified strategy classes) to allow fancy text to be displayed for the value "fancy" provided for the style parameter. It should use the font Font ("Serif", Font.ITALIC, 12). (3) 5.4 Explain what changes are necessary to the TextApplet class for this. (2)

0 Answers   TCS,

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What are the main uses of this keyword?

0 Answers  

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What sorting algorithm does javascript use?

0 Answers  

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I have a Arraylist object, it has duplecate values also. Now question is i want delete duplecate data in that objet with out using Set?

8 Answers   Aricent,

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What are the differences between heap and stack memory in java?

0 Answers  

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Does sprintf allocate memory?

0 Answers  

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What is a Presistent Object?

0 Answers   InfoAxon Technologies,

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What is an example of a constant variable?

0 Answers  

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how to handle exceptions in core applications?

2 Answers   CSS,

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