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Showing posts with label Java. Show all posts
Showing posts with label Java. Show all posts

Wednesday, April 29, 2020

April 29, 2020

JAVA ONE LINER PART 08

JAVA ONE LINER PART 08

1) What are identifiers and what is naming convention?
Ans : Identifiers are used for class names, method names and variable names. An identifier may be any descriptive sequence of upper case & lower case letters,numbers or underscore or dollar sign and must not begin with numbers.

2) What is the return type of program’s main( ) method?
Ans : void

3) What is the argument type of program’s main( ) method?
Ans : string array. 

 
4) Which characters are as first characters of an identifier?
Ans : A – Z, a – z, _ ,$ 

 
5) What are different comments?
Ans : 1) // -- single line comment
2) /* --  */ multiple line comment
3) /** -- */ documentation


6) What is the difference between constructor method and method?
Ans : Constructor will be automatically invoked when an object is created. Whereas method has to be call explicitly.

7) What is the use of bin and lib in JDK?
Ans : Bin contains all tools such as javac, applet viewer, awt tool etc., whereas Lib contains all packages and variables.
April 29, 2020

JAVA ONE LINER PART 07

JAVA ONE LINER PART 07

1.The Java interpreter is used for the execution of the source code.
a)True                
b)False
Ans: a.

2) On successful compilation a file with the class extension is created.
a) True               
b) False
Ans: a.

3) The Java source code can be created in a Notepad editor.
a) True                 
b) False
Ans: a.

4) The Java Program is enclosed in a class definition.
a) True                 
b) False
Ans: a.

5) What declarations are required for every Java application?
Ans: A class and the main( ) method declarations.

6) What are the two parts in executing a Java program and their purposes?
Ans: Two parts in executing a Java program are:
Java Compiler and Java Interpreter.
The Java Compiler is used for compilation and the Java Interpreter is used for execution of the application.

7) What are the three OOPs principles and define them?
Ans : Encapsulation, Inheritance and Polymorphism are the three OOPs
Principles.
Encapsulation:
Is the Mechanism that binds together code and the data it manipulates, and keeps both safe from outside interference and misuse.
Inheritance:
Is the process by which one object acquires the properties of another object.
Polymorphism:
Is a feature that allows one interface to be used for a general class of actions.

8) What is a compilation unit?
Ans : Java source code file.

9) What output is displayed as the result of executing the following statement?
a) System.out.println("// Looks like a comment.");
b) // Looks like a comment
c) The statement results in a compilation error
d) Looks like a comment
e) No output is displayed
Ans : a.

10) In order for a source code file, containing the public class Test, to successfully compile, which of the following must be true?
a) It must have a package statement
b) It must be named Test.java
c) It must import java.lang
d) It must declare a public class named Test
Ans : b

Tuesday, April 28, 2020

April 28, 2020

JAVA MCQS PART 06

JAVA MCQS PART 06

1. <script type="text/javascript">
x=4+"4";
document.write(x);
</script>
Output------?
A. 44          
B. 8         
C. 4          
D. Error output
Ans: A

2. Is it possible to nest functions in JavaScript?
A. True                       
B. False
Ans: A

3. <script>
document.write(navigator.appCodeName);
</script>
A. get code name of the browser of a visitor
B. set code name of the browser of a visitor     
C. None of the above
Ans: A

4. Scripting language are
A. High Level Programming language     
B. Assembly Level programming language
C. Machine level programming language
Ans: A

 
5. Which best explains getSelection()?
A. Returns the VALUE of a selected OPTION.
B. Returns document.URL of the window in focus.
C. Returns the value of cursor-selected text
D. Returns the VALUE of a checked radio input.
Ans: C

 
6. Choose the client-side JavaScript object:
A. Database      
B. Cursor         
C. Client         
D. FileUpLoad
Ans: D

7. What is mean by "this" keyword in javascript?
A. It refers current object                   
B. It referes previous object
C. It is variable which contains value            
D. None of the above
Ans: A

8. In JavaScript, Window.prompt() method return true or false value ?
A. False            
B. True
Ans: A

9. <script language="javascript">
function x()
{
document.write(2+5+"8");
}
</script>
A. 258         
B. Error        
C. 7           
D. 78
Ans: D

10. <script type="text/javascript">
var s = "9123456 or 80000?";
var pattern = /\d{4}/;
var output = s.match(pattern);
document.write(output);
</script>
A. 9123         
B. 91234         
C. 80000           
D. None of the above
Ans: A
April 28, 2020

JAVA MCQS PART 05

JAVA MCQS PART 05

1.  When a JavaScript object is sent to Java, the runtime engine creates a Java wrapper of type ___________
A.  ScriptObject           
B.  JSObject         
C.  JavaObject         
D.  Jobject
Ans: B

2.  _______ class provides an interface for invoking JavaScript methods and examining JavaScript properties.
A.  ScriptObject         
B.  JSObject        
C.  JavaObject          
D.  Jobject
 Ans: B

3.  _________ is a wrapped Java array, accessed from within JavaScript code.
A.  JavaArray          
B.   JavaClass     
C.  JavaObject        
D.  JavaPackage
 Ans:  A
  
4. A ________ object is a reference to one of the classes in a Java package, such as netscape.javascript .
A.  JavaArray       
B.  JavaClass          
C.  JavaObject         
D.  JavaPackage
 Ans: B

5.  The JavaScript exception is available to the Java code as an instance of __________
A.  netscape.javascript.JSObject      
B.  netscape.javascript.JSException
C.  netscape.plugin.JSException          
D.  None of the above
Ans: B

6. To automatically open the console when a JavaScript error occurs which of the following is added to prefs.js?
A.  user_pref(" javascript.console.open_on_error", false);
B.  user_pref("javascript.console.open_error ", true);
C.  user_pref("javascript.console.open_error ", false);
D.  user_pref("javascript.console.open_on_error", true);
Ans: D

7.  To open a dialog box each time an error occurs, which of the following is added to prefs.js?
A.  user_pref("javascript.classic.error_alerts", true);
B.  user_pref("javascript.classic.error_alerts ", false);
C.  user_pref("javascript.console.open_on_error ", true);
D.  user_pref("javascript.console.open_on_error ", false);
 Ans: A

8.  The syntax of a blur method in a button object is ______________
A.  Blur()         
B.   Blur(contrast)      
C.  Blur(value)       
D.  Blur(depth)
 Ans: A

9.  The syntax of capture events method for document object is ______________
A.  captureEvents()         
B.   captureEvents(argseventType)
C.  captureEvents(eventType)     
D.  captureEvents(eventVal)
 Ans: C

10.  The syntax of close method for document object is ______________
A.  Close(doC.         
B.   Close(object)  
C.  Close(val)       
D.  Close()
Ans: D
April 28, 2020

JAVA MCQS PART 04

JAVA MCQS PART 04

1.  JavaScript is interpreted by _________
A.  Client         
B.   Server      
C.  Object        
D.  None of the above
Ans: A

2.  Using _______ statement is how you test for a specific condition.
A.  Select         
B.  If          
C.  Switch           
D.  For
 Ans: B

3.  Which of the following is the structure of an if statement?
A.  if (conditional expression is true) thenexecute this codeend if
B.  if (conditional expression is true)execute this codeend if
C.  if (conditional expression is true)   {then execute this code>->}
D.  if (conditional expression is true) then {execute this code}
Ans: C

4.  How to create a Date object in JavaScript?
A.  dateObjectName = new Date([parameters])
B.  dateObjectName.new Date([parameters])
C.  dateObjectName := new Date([parameters])
D.  dateObjectName Date([parameters])
 Ans: A

5.  The _______ method of an Array object adds and/or removes elements from an array.
A.  Reverse       
B.   Shift          
C.  Slice          
D.  Splice
 Ans: D

6.  To set up the window to capture all Click events, we use which of the following statement?
A.  window.captureEvents(Event.CLICK);
B.  window.handleEvents (Event.CLICK);
C.  window.routeEvents(Event.CLICK );
D.  window.raiseEvents(Event.CLICK );
 Ans: A

7.  Which tag(s) can handle mouse events in Netscape?
A.  <IMG>           
B.  <A>           
C.  <BR>           
D.  None of the above
 Ans: B

8.  ____________ is the tainted property of a window object.
A.  Pathname          
B.   Protocol      
C.  Defaultstatus     
D.  Host
 Ans: C

9.  To enable data tainting, the end user sets the _________ environment variable.
A.  ENABLE_TAINT                
B.   MS_ENABLE_TAINT  
C.  NS_ENABLE_TAINT       
D.  ENABLE_TAINT_NS
 Ans: C

10.  In JavaScript, _________ is an object of the target language data type that encloses an object of the source language.
A.  a wrapper         
B.   a link        
C.  a cursor        
D.  a form
Ans: A
April 28, 2020

JAVA MCQS PART 03

JAVA MCQS PART 03

1. What does the <noscript> tag do?
A. Enclose text to be displayed by non-JavaScript browsers.
B. Prevents scripts on the page from executing.
C. Describes certain low-budget movies.    
D. None of the above
 Ans: A

2. If para1 is the DOM object for a paragraph, what is the correct syntax to change the text within the paragraph?
A.  "New Text"?                
B.  para1.value="New Text";
C.  para1.firstChild.nodeValue= "New Text";
D.  para1.nodeValue="New Text";
Ans: B

3.  JavaScript entities start with _______ and end with _________.
A.  Semicolon, colon            
B.   Semicolon, Ampersand
C.  Ampersand, colon                 
D.  Ampersand, semicolon
 Ans: D

4.  Which of the following best describes JavaScript?
A. a low-level programming language.
B. a scripting language precompiled in the browser.
C. a compiled scripting language.
D. an object-oriented scripting language.
 Ans: D

5.  Choose the server-side JavaScript object?
A.  FileUpLoad      
B.   Function          
C.  File        
D.  Date
Ans: C
 

6.  Choose the client-side JavaScript object?
A.  Database          
B.   Cursor       
C.  Client         
D.  FileUpLoad
Ans: D
 
7.  Which of the following is not considered a JavaScript operator?
A.  new          
B.  this      
C.  delete        
D.  typeof
 Ans: B

8.  ______method evaluates a string of JavaScript code in the context of the specified object.
A.  Eval      
B.   ParseInt          
C.  ParseFloat      
D.  Efloat
 Ans: A

9.  Which of the following event fires when the form element loses the focus: <button>, <input>, <label>, <select>, <textarea>?
A.  onfocus           
B.  onblur        
C.  onclick      
D.  ondblclick
 Ans: B

10.  The syntax of Eval is ________________
A.  [objectName.]eval(numeriC.     
B.  [objectName.]eval(string)
C.  [EvalName.]eval(string)            
D.  [EvalName.]eval(numeriC.
Ans: B
April 28, 2020

JAVA MCQS PART 02

JAVA MCQS PART 02

1.  ______ tag is an extension to HTML that can enclose any number of JavaScript statements.
A.  <SCRIPT>          
B.   <BODY>        
C.  <HEAD>            
D.  <TITLE>
Ans: A

2.  How does JavaScript store dates in a date object?
A.  The number of milliseconds since January 1st, 1970
B.   The number of days since January 1st, 1900
C.  The number of seconds since Netscape's public stock offering.
D.  None of the above
Ans: A

3.  Which of the following attribute can hold the JavaScript version?
A.  LANGUAGE         
B.   SCRIPT       
C.  VERSION      
D.  None of the above
Ans: A

 
4.  What is the correct JavaScript syntax to write "Hello World"?
A.  System.out.println("Hello World")  
B.   println ("Hello World")
C.  document.write("Hello World")    
D.  response.write("Hello World")
Ans: C

5.  Which of the following way can be used to indicate the LANGUAGE attribute?
A.  <LANGUAGE="JavaScriptVersion">
B.   <SCRIPT LANGUAGE="JavaScriptVersion">
C.  <SCRIPT LANGUAGE="JavaScriptVersion">    JavaScript statements…</SCRIPT>
D.  <SCRIPT LANGUAGE="JavaScriptVersion"!>    JavaScript statements…</SCRIPT>
Ans: C

6.  Inside which HTML element do we put the JavaScript?
A.  <js>         
B.   <scripting>         
C.  <script>      
D.  <javascript>
Ans: C

7.  What is the correct syntax for referring to an external script called " abc.js"?
A.  <script href=" abc.js">                    
B.   <script name=" abc.js">
C.  <script src=" abc.js">                      
D.  None of the above
Ans: C

8.  Which types of image maps can be used with JavaScript?
A.  Server-side image maps             
B.  Client-side image maps
C.  Server-side image maps and Client-side image map 
D.  None of the above
Ans: B

9.  Which of the following navigator object properties is the same in both   Netscape and IE?
A. navigator.appCodeName                  
B. navigator.appName
C. navigator.appVersion                           
D. None of the above 

Ans: A

10.  Which is the correct way to write a JavaScript array?
A. var txt = new Array(1:"tim",2:"kim",3:"jim")
B. var txt = new Array:1=("tim")2=("kim")3=("jim")
C. var txt = new Array("tim","kim","jim")
D. var txt = new Array="tim","kim","jim"
Ans: C
April 28, 2020

JAVA MCQS PART 01

JAVA MCQS PART 01

1. Why so JavaScript and Java have similar name?
A.  JavaScript is a stripped-down version of Java
B.  JavaScript's syntax is loosely based on Java's
C.  They both originated on the island of Java
D.  None of the above
Ans: B

2.  When a user views a page containing a JavaScript program, which machine actually executes the script?
A.  The User's machine running a Web browser   
B.  The Web server
C.  A central machine deep within Netscape's corporate offices
D.  None of the above
Ans:  A

3.  ______ JavaScript is also called client-side JavaScript.
A.  Microsoft     
B.  Navigator 
C.  LiveWire     
D.  Native
Ans: B

4.  __________ JavaScript is also called server-side JavaScript.
A.  Microsoft          
B.   Navigator       
C.  LiveWire      
D.  Native
 Ans: C

5.  What are variables used for in JavaScript Programs?
A.  Storing numbers, dates, or other values      
B.   Varying randomly
C.  Causing high-school algebra flashbacks       
D.  None of the above
 Ans: A

6.  _____ JavaScript statements embedded in an HTML page can respond to user events such as mouse-clicks, form input, and page navigation.
A.  Client-side           
B.   Server-side          
C.  Local      
D.  Native
 Ans: A

7.  What should appear at the very end of your JavaScript?
The <script LANGUAGE="JavaScript">tag
A. The </script>  
B. The <script> 
C. The END statement
D. None of the above
Ans: A

8.  Which of the following can't be done with client-side JavaScript?
A.  Validating a form
B.   Sending a form's contents by email
C.  Storing the form's contents to a database file on the server
D.  None of the above
 Ans: C

9.  Which of the following are capabilities of functions in JavaScript?
A.  Return a value        
B.   Accept parameters and Return a value
C.  Accept parameters         
D.  None of the above
 Ans: C

10.  Which of the following is not a valid JavaScript variable name?
A.  2names       
B.   _first_and_last_names
C.  FirstAndLast     
D.  None of the above
 Ans: A