Difference between revisions of "Java/C2/Errors-and-Debugging-in-Eclipse/English-timed"

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| 00:30
 
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|how to create and run a '''Java Program '''in '''Eclipse.'''
 
|how to create and run a '''Java Program '''in '''Eclipse.'''
−
 
  
 
|-
 
|-
 
| 00:33
 
| 00:33
−
|If not, for relevant tutorial please visit our website as shown. [http://spoken-tuitorial.org/]
+
|If not, for relevant tutorial please visit our website as shown. [http://spoken-tuitorial.org]
  
 
|-
 
|-
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|-
 
|-
 
| 00:55
 
| 00:55
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|We shall write a program and then make each of these errors and see what happens in '''Eclipse'''
+
|We shall write a program and then make each of these errors and see what happens in '''Eclipse'''.
  
 
|-
 
|-
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|-
 
|-
 
| 01:11
 
| 01:11
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|We shall  create  a new  '''class''' in the project and use it as '''New''' Class. Let us name the class ''' Error Free''' and select '''methods stubs''' '''public static void main'''.
+
|We shall  create  a new  '''class''' in the project and use it.  '''New''' '''Class'''. Let us name the class ''' ErrorFree''' and select '''methods stubs''' '''public static void main'''.
  
 
|-
 
|-
 
| 01:37
 
| 01:37
−
| Let us minimize the package explorer. Remove the comments and add the print statement with the few errors.
+
| Let us minimize the package explorer. Remove the comments and add the print statement with a few errors.
  
 
|-
 
|-
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|-
 
|-
 
|  02:51
 
|  02:51
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|  The first error displayed is syntax error insert  semi-colon to complete block statements  
+
|  The first error displayed is: '''syntax error, insert  semi-colon to complete block statements'''.
  
 
|-
 
|-
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|-
 
|-
 
|  03:16
 
|  03:16
−
| notice that once we add the semi-colon and save the file, the first error is gone.
+
| Notice that once we add the semi-colon and save the file, the first error is gone.
 
   
 
   
 
|-
 
|-
 
| 03:21
 
| 03:21
−
|their is only one error now which says; '''hello world cannot be resolved to a variable''', which means to display any message on the console the message has to be included in double quotes.
+
|There is only one error now which says: '''Helloworld cannot be resolved to a variable''' which means to display any message on the console the message has to be included in '''double quotes'''.
 
   
 
   
 
|-
 
|-
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|-
 
|-
 
|  03:41
 
|  03:41
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|  Let us add double quotes before and after the message,  
+
|  Let us add double quotes before and after the message.  
  
 
|-
 
|-
 
| 03:55
 
| 03:55
−
|''' Ctrl s'''  to Save. We see that the red cross mark have gone and the program is error free. So let us ''' run''' the program and see what happens.
+
|''' Ctrl s'''  to Save. We see that the red cross mark is gone and the program is error free. So, let us '''run''' the program and see what happens.
  
 
|-
 
|-
 
|  04:10
 
|  04:10
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|  Run as '''Java applications''  
+
|  '''Run as''' > '''Java applications''  
 
   
 
   
 
|-
 
|-
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| 04:25
 
| 04:25
 
|It happens due to a mismatch of '''file name''' and '''class name.'''
 
|It happens due to a mismatch of '''file name''' and '''class name.'''
−
 
  
 
|-
 
|-
 
| 04:29
 
| 04:29
 
|It does not  happens usually on '''Eclipse.'''
 
|It does not  happens usually on '''Eclipse.'''
−
 
  
 
|-
 
|-
 
| 04:31
 
| 04:31
−
|This is because we use the '''New Class wizard''' to create a file and eclipse
+
|This is because we use the '''New Class wizard''' to create a file and '''eclipse'''
−
 
+
  
 
|-
 
|-
 
| 04:39
 
| 04:39
−
|creates a file automatically
+
|creates a file automatically.
  
 
|-
 
|-
 
| 04:41
 
| 04:41
−
|  But if we create a '''Java file''' outside of '''Eclipse''' and add it to a project, their is the chance of the error  
+
|  But if we create a '''Java file''' outside of '''Eclipse''' and add it to a project, there is a chance of the error.
−
 
+
  
 
|-
 
|-
 
| 04:47
 
| 04:47
−
|So let us stimulate the error , by changing  the class name.
+
|So let us stimulate the error by changing  the '''class name'''.
−
 
+
−
 
+
  
 
|-
 
|-
 
|04:59
 
|04:59
−
|Since Java is case-sensitive, now the class name and file name do not match .  
+
|Since Java is ''case sensitive'', now the '''class name''' and '''file name''' do not match .  
−
 
+
  
 
|-
 
|-
 
|05:09
 
|05:09
−
|Notice that , there is a '''red cross mark '''on the left margin.
+
|Notice that there is a '''red cross mark '''on the left margin.
  
 
|-
 
|-
 
|05:14
 
|05:14
−
|   And error message reads '''The public type errorfree must be defined in its own file'''.
+
| And error message reads '''The public type errorfree must be defined in its own file'''.
−
 
+
−
 
+
 
   
 
   
 
|-
 
|-
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|-
 
|-
 
|  05:29
 
|  05:29
−
|  ''' Eclipse offers intelligent fixes and we have 2 fixes available here   
+
|  '''Eclipse''' offers intelligent fixes and we have 2 fixes available here.  
−
 
+
−
 
+
  
 
|-
 
|-
 
| 05:35
 
| 05:35
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|  The first one is '''rename compilation unit to errorfree java'''
+
|  The first one is '''Rename compilation unit to errorfree java'''
 
|-
 
|-
 
| 05:39
 
| 05:39
−
| The second one is   ''''rename  the type to errorfree '''.  
+
| The second one is '''Rename the type to errorfree'''.  
 
|-
 
|-
 
|  05:43
 
|  05:43
−
|The fix that we are looking to is the second one. And we see that once you rename the file the class back to errorfree the error here is missing.
+
|The fix that we are looking for is the second one. And we see that once you rename the file,the '''class''' back to 'ErrorFree', the error here is missing.
−
 
+
  
 
|-
 
|-
 
| 06:03  
 
| 06:03  
 
|The next error happens due to typing mistakes in the print statement.
 
|The next error happens due to typing mistakes in the print statement.
−
 
  
 
|-
 
|-
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|-
 
|-
 
| 06:15  
 
| 06:15  
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|  We notice that their is the ''' red-cross mark'''   
+
|  We notice that there is the ''' red-cross mark'''   
−
 
+
  
 
|-
 
|-
 
|  06:18
 
|  06:18
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| And error message reads  '''system cannot be resolved.'''
+
| and error message reads  '''system cannot be resolved.'''
−
 
+
  
 
|-
 
|-
 
|  06:23
 
|  06:23
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|This means, Java is expecting a class or object or a  variable by the name '''system.'''
+
|This means, Java is expecting a '''class''' or '''object''' or a  '''variable''' by the name 'system'.
−
 
+
  
 
|-
 
|-
 
|  06:28
 
|  06:28
−
|But there is nothing like system object in the code.
+
|But there is nothing like 'system' object in the code.
 
|-
 
|-
 
|  06:33
 
|  06:33
−
|So let us look at the possible fixes..
+
|So, let us look at the possible fixes.
  
 
|-
 
|-
 
| 06:39
 
| 06:39
−
|there are '''11 fixes''' out of these, fix that we are looking for is the eighth option
+
|There are '''11 fixes''', out of these the fix that we are looking for is the eighth option:
−
 
+
−
 
+
  
 
|-
 
|-
 
|  06:48
 
|  06:48
−
|'''Change to 'System' '''(java.lang)'''
+
|'''Change to 'System' (java.lang)'''
−
 
+
  
 
|-
 
|-
 
|  06:58
 
|  06:58
−
|You can see that once we change it to capital 'S' the error is missing.
+
|You can see that once we change it to capital 'S' the error is missing.
 
|-
 
|-
 
|  07:06
 
|  07:06
−
|  here is  how you identify errors in Java using eclipse and rectify them   
+
|  Here is  how you identify errors in Java using '''eclipse''' and rectify them.  
 
|-
 
|-
 
|  07:15  
 
|  07:15  
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|-
 
|-
 
|  07:18
 
|  07:18
−
|In this tutorial we have seen
+
|In this tutorial we have seen:
 
|-
 
|-
 
|  07:20
 
|  07:20
−
|'''what are the typical errors while writing a Java program''' and  
+
|what are the typical errors while writing a Java program and  
  
 
|-
 
|-
 
|  07:23
 
|  07:23
−
|how to '''identify them and rectify them using Eclipse'''.
+
|how to identify them and rectify them using '''Eclipse'''.
  
 
|-
 
|-
 
|  07:30
 
|  07:30
−
|As an assignment for this tutorial,  find out the error in the code given below and fix them
+
|As an assignment for this tutorial,  find out the errors in the code given below and fix them.
  
 
|-
 
|-
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|-
 
|-
 
|  07:42
 
|  07:42
−
| Watch the video available at the following link, It summarises the project.  
+
| watch the video available at the following link. It summarizes the project.  
  
 
|-
 
|-
 
|  07:48
 
|  07:48
−
|If you do not have good bandwidth, you can download and watch it
+
|If you do not have good bandwidth, you can download and watch it.
−
+
  
 
|-
 
|-
 
|  07:53
 
|  07:53
−
|  The Spoken Tutorial Team conducts workshops using '''spoken tutorials'''.
+
|  The Spoken Tutorial Team conducts workshops using '''spoken tutorials'''.
−
 
+
  
 
|-
 
|-
 
|  07:57
 
|  07:57
 
|Gives certificates for those who pass an online test. For more details, please write to
 
|Gives certificates for those who pass an online test. For more details, please write to
−
 
 
  '''contact AT spoken HYPHEN tutorial DOT org.'''
 
  '''contact AT spoken HYPHEN tutorial DOT org.'''
  
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| 08:07
 
| 08:07
 
|  '''Spoken Tutorial''' Project is a part of the '''Talk to a Teacher''' project.
 
|  '''Spoken Tutorial''' Project is a part of the '''Talk to a Teacher''' project.
−
 
  
 
|-
 
|-
−
| 08:11
+
| 08:11
 
|It is supported by the '''National Mission on Education through ICT, MHRD, Government of India'''.
 
|It is supported by the '''National Mission on Education through ICT, MHRD, Government of India'''.
−
 
  
 
|-
 
|-
−
| 08:17
+
| 08:17
 
|More information on this Mission is available at
 
|More information on this Mission is available at
−
 
 
  '''spoken HYPHEN tutorial DOT org SLASH NMEICT HYPHEN Intro'''
 
  '''spoken HYPHEN tutorial DOT org SLASH NMEICT HYPHEN Intro'''
  
 
|-
 
|-
−
|     08:23
+
| 08:23
 
| This tutorial has been contributed by '''TalentSprint'''.
 
| This tutorial has been contributed by '''TalentSprint'''.
  
 
Thanks for joining.
 
Thanks for joining.
 
|-
 
|-

Revision as of 17:59, 19 March 2015

Time Narration
00:01 Welcome to the tutorial on Errors and Debugging using Eclipse.
00:07 In this tutorial, we are going to learn:
00:10 what are the possible errors while writing a simple Java program,
00:14 how to identify those errors and rectify them using eclipse.
00:20 For this tutorial we are using

Ubuntu 11.10 and

Eclipse 3.7.

00:27 To follow this tutorial, you must know
00:30 how to create and run a Java Program in Eclipse.
00:33 If not, for relevant tutorial please visit our website as shown. [1]
00:41 In a simple Java program, the typical errors could be:
00:45 * Missing semicolon(;)
00:47 * Missing double quotes(" ") around the message
00:50 * Mis-match of filename and classname and
00:52 * Typing the print statement in lower-case.
00:55 We shall write a program and then make each of these errors and see what happens in Eclipse.
01:04 Here we have the Eclipse IDE and the project used for the HelloWorld tutorial.
01:11 We shall create a new class in the project and use it. New Class. Let us name the class ErrorFree and select methods stubs public static void main.
01:37 Let us minimize the package explorer. Remove the comments and add the print statement with a few errors.
02:23 In Eclipse, the line which has the error will be indicated with a red cross mark on the left margin.

Java/C2/Errors-and-Debugging-in-Eclipse/English-timed

02:35 In this case, the System.out.println line has an error and hence there is a red cross mark on the left.
02:44 The list of errors is displayed by hovering the mouse over the cross mark.
02:51 The first error displayed is: syntax error, insert semi-colon to complete block statements.
02:58 This is because we have to end every statement of a program with a semicolon.
03:03 So, let us insert semicolon at the end of the statement.
03:08 Save the file with Ctrl s.
03:16 Notice that once we add the semi-colon and save the file, the first error is gone.
03:21 There is only one error now which says: Helloworld cannot be resolved to a variable which means to display any message on the console the message has to be included in double quotes.
03:37 Without the quotes, Java thinks that HelloWorld is the name of a variable.
03:41 Let us add double quotes before and after the message.
03:55 Ctrl s to Save. We see that the red cross mark is gone and the program is error free. So, let us run the program and see what happens.
04:10 Run as' > Java applications
04:15 We see that the message has been printed on the console.
04:22 Let us look at the next error.
04:25 It happens due to a mismatch of file name and class name.
04:29 It does not happens usually on Eclipse.
04:31 This is because we use the New Class wizard to create a file and eclipse
04:39 creates a file automatically.
04:41 But if we create a Java file outside of Eclipse and add it to a project, there is a chance of the error.
04:47 So let us stimulate the error by changing the class name.
04:59 Since Java is case sensitive, now the class name and file name do not match .
05:09 Notice that there is a red cross mark on the left margin.
05:14 And error message reads The public type errorfree must be defined in its own file.
05:20 Also notice that the word errorfreeis underlined in red colour.
05:29 Eclipse offers intelligent fixes and we have 2 fixes available here.
05:35 The first one is Rename compilation unit to errorfree java
05:39 The second one is Rename the type to errorfree.
05:43 The fix that we are looking for is the second one. And we see that once you rename the file,the class back to 'ErrorFree', the error here is missing.
06:03 The next error happens due to typing mistakes in the print statement.
06:09 Let us replace the capital S with a small s.
06:15 We notice that there is the red-cross mark
06:18 and error message reads system cannot be resolved.
06:23 This means, Java is expecting a class or object or a variable by the name 'system'.
06:28 But there is nothing like 'system' object in the code.
06:33 So, let us look at the possible fixes.
06:39 There are 11 fixes, out of these the fix that we are looking for is the eighth option:
06:48 Change to 'System' (java.lang)
06:58 You can see that once we change it to capital 'S' the error is missing.
07:06 Here is how you identify errors in Java using eclipse and rectify them.
07:15 This brings us to the end of this tutorial.
07:18 In this tutorial we have seen:
07:20 what are the typical errors while writing a Java program and
07:23 how to identify them and rectify them using Eclipse.
07:30 As an assignment for this tutorial, find out the errors in the code given below and fix them.
07:39 To know more about the Spoken Tutorial project,
07:42 watch the video available at the following link. It summarizes the project.
07:48 If you do not have good bandwidth, you can download and watch it.
07:53 The Spoken Tutorial Team conducts workshops using spoken tutorials.
07:57 Gives certificates for those who pass an online test. For more details, please write to 
contact AT spoken HYPHEN tutorial DOT org.
08:07 Spoken Tutorial Project is a part of the Talk to a Teacher project.
08:11 It is supported by the National Mission on Education through ICT, MHRD, Government of India.
08:17 More information on this Mission is available at 
spoken HYPHEN tutorial DOT org SLASH NMEICT HYPHEN Intro
08:23 This tutorial has been contributed by TalentSprint.

Thanks for joining.

Contributors and Content Editors

Gaurav, Madhurig, PoojaMoolya, Pravin1389, Sandhya.np14, Sneha

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