Answer Posted / sujith

Java is not purely objected oriented because it does not support multiple inheritance and operative overloading. But multiple inheritance is possible with the help of interfaces.

Explain the difference between throw and throws in java?

946

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From the two, which would be easier to write: synchronization code for ten threads or two threads?

999

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What are the methods to rectify ambiguities in the interfaces in JAVA?

1028

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What will happen if a thrown exception is not handled?

953

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What is jvm? How its run?

1018

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What are inner classes or non static nested classes in java?

1119

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Can we overload the methods by making them static?

944

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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)

2229

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What is an interface in java?

1007

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What are different access specifiers in java?

949

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What is meant by singleton class?

980

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What is type inference in java8?

976

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How can we make sure main() is the last thread to finish in java program?

1143

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Which method cannot be overridden in java?

945

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What is pass by value?

894

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