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CS2023-AJP UNIT-1 PART-A
UNIT I JAVA FUNDAMENTALS
Java I/O streaming – filter and pipe streams – Byte Code interpretation - Threading – Swing.
Important Two Marks Q & A
1. What are Byte streams?
Byte streams provide a convenient means for handling input and output of bytes.
Byte streams are used for example when reading or writing binary data
2. How does pipe differ from filter Stream? [May / June 2011 ]
PipedInputStream and PipedOutputStream Classes implements Input and Output
Components Of a Pipe. Pipes are used to channel the output from one program
(or thread) into the input of another
FilterInputStream and FilterOutputStream Classes Implements Filter Streams ,
Filter used to modify data read from an underlying stream
3. What is a java Bytecode? [May / June 2012 ]
Java bytecode is the form of instructions that java virtual machine executes ,Each
bytecode opcode is one byte in length
4. Write any four advantages of swing components [May / June 2011 ]


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Swing components are lightweight
It provides Java programmers many new powerful components
Swing provides built-in double buffering
Swing provides paint debugging support for when you build your own
components
5. What is Multithreading? List out the stages involved in thread life cycle
[Nov/Dec 2012 ]
Multithreading is a process of executing multiple threads simultaneously.
Thread is basically a lightweight subprocess, a smallest unit of processing.
Multiprocessing and multithreading, both are used to achieve multitasking.
Thread Stages:




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New Stage
Runnable
Running State
Dead State
Blocked
6. List out Filter Stream classes
BufferedInputStream,BufferedOutputStream
DataInputStream,DataOutputStream
PrintStream
PushbackInputStream
GZIPInputStream,GZIPOutputStream
DigestInputStream, DigestOutputStream
ChiperInputSTream, ChiperOutputSTream
L. Maria Michael Visuwasam, A.P, CSE, VIT
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CS2023-AJP UNIT-1 PART-A
ObjectInputStream, ObjectOutputStream
7. Write a java code to copy characters from a file to another file [Nov /
Dec 2011 ]
import java.io.FileInputStream;
import java.io.FileOutputStream;
import java.io.IOException;
public class CopyFile2File {
public static void main(String[] args) {
String str = "Hi this is data to copy from one file to another file...";
try{
FileOutputStream fos = new FileOutputStream("hello2.dat");
byte b[] = str.getBytes();
fos.write(b);
fos.close();
System.out.println("The file hello2 is created with string data");
FileInputStream fis = new FileInputStream("hello2.dat");
System.out.println("Read the data from hello2.dat");
fos = new FileOutputStream("temp.dat");
String str1= "";
int size = fis.available();
int ch;
System.out.println("Size of file :"+size);
while((ch=fis.read())!= -1){
str1 = str1+(char)ch;
}
byte b1[] = str1.getBytes();
fos.write(b1);
fos.close();
fis.close();
System.out.println("the data of hello2.dat copied to temp.dat");
}catch(IOException ioe){
ioe.printStackTrace();
}
}
}
8. Define JVM [ May /June 2012 ]
A Java virtual machine (JVM) is a virtual machine that can execute Java
bytecode. It is the code execution component of the Java platform.
A Java virtual machine (JVM), an implementation of the Java Virtual Machine
Specification, interprets compiled Java binary code for a computer's processor
9. List out two main Stream classes and two sub classes in each stream
Used in Java ? [Nov/Dec 2012 ]
L. Maria Michael Visuwasam, A.P, CSE, VIT
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CS2023-AJP UNIT-1 PART-A
10.Give the syntax and use of any four classes in swing? [Nov/Dec 2007 ]

JTextField allows editing of a single line of text. New features include the
ability to justify the text left, right, or center, and to set the text’s font.

JPasswordField (a direct subclass of JTextField) you can suppress the
display of input. Each character entered can be replaced by an echo character.

JCheckBox is not a member of a checkbox group. A checkbox can be
selected and deselected, and it also displays its current state.

JComboBox is like a drop down box. You can click a drop-down arrow and
select an option from a list.
11.What are the benefits in using swings compared to awt?




Swing provide both additional components and added functionality to AWT
– replacement Components
Swing Components are lightweight
Swing provides built-in double buffering
Swing provide paint debugging support for when you build your own
components
L. Maria Michael Visuwasam, A.P, CSE, VIT
Page 3