0:06 So now the first topic in S.E.J.P. So keep subheading, language fundamentals. Language fundamentals. Language fundamentals. Okay, in the, there are few topics what we have to discuss. So the first one, first topic, we will discuss about, okay, we will discuss about what are various identifiers? Sir, how we can define identifier? what rules are there? like we are going to discuss first identifiers and then we will go for what are various reserve rules in Java after that we can go for
0:55 data types data types, after that data types and then we can talk about literals, literals and then erase concept data types, laterals, erase and after completing erase after completing erase concept then we can go for types of variables types of variables types of variables and after types of variables the next subtopic what we have to discuss is where arg methods where arg methods and then main method, where are the methods? Main method
1:42 and after that Java here main method and after completing command line arguments command line arguments command line arguments and then Java coding standards Java coding standards Okay, that's all. Sir, these are various loopholes, I mean various, this is the agenda for the first ten sessions almost. So, related to language fundamentals, the syllabus, right? Better to take all. This is the agenda for language fundamentals. Identifiers, reserved words, data types, literals, arrays,
2:33 extra types of variables, hierarch method, hierarch method, main method, command line arguments and then Java coding standards, Java coding standards, like so this is the agenda for language fundamentals what we have So almost ten sessions we are going to talk but a bit basic concepts but compulsory you people should have clear clarity about these things. A bit basics anyway right? Now keep subheading.
3:24 So basic concept but still you people are going to get several several new things. This is the agenda for language fundamentals right. Now keep submitting the first one identifiers. The first one identifiers. Identifiers. Sir can you tell what is identifier? Identifier which can be used for identification purpose. Assume that in our class hundred students are there. How I can identify each person by using Name, hello Ravi, Pawan, Shiva, like by using name we can identify each person. So a name, name in Java program is by default considered as identifier which can be
4:14 used for identification purpose. Are you getting? A name in Java program is by default considered as identifier which can be used for identification purpose. So it can be a class name or it can be a mother name. or variable name or label name. Labels also. Sometimes, do you know, we have some code like this. L1, label L1 is nothing but like. Or label L2 like this. So, a name in Java program is by default considered as identifier. It can be a class name, method name, variable name or label name. Are you able to understand that? Okay? This is. So, add. A name, a name in Java program, a name In Java program a name in Java program in Java program is
5:04 called identifier a name in Java program is called identifier a name in Java program is called identifier is called identifier identifier which can be used for which can be used for which can be used for identification purpose Which can be used for identification purpose Which can be used for identification purpose purpose purpose It can be it can be it can be it can be methadonym It can be methadonym methadonym methadonym or variable name it can be methadonym variable name It can be methadonym
5:54 variable name class name Class name, class name or label name or label, label name, name or label, label name So a name in Java program by default considered as what? Identifier, right? Are you able to understand? Okay? Best example here see this one. Let me take a simple example for you people Sir I am taking class test. Analegion well because first example so class test Public static wired main method and string array
6:39 action Here I am taking system.out.println Hello like I am taking right system data would printl and of hello or otherwise one minute one minute here int x is equal to 10 that's all I don't want to take s for p int x is equal to 10 Can you tell almost smallest java program? In this how many identifiers are there? Why? Don't tell wrong answer because it's the first one How many how many identifiers are there? So I hope you people got clear what is identifier?
7:25 A name in Java program is by default considered as identifier. It can be a class name, method name, variable name or label name. So a name in Java program is identifier. Can you tell how many identifiers are there in this? Three or four? Three or four? Four or five? How many identifiers are there? Make sure the first identifier is a test or name of class, class name, name of the class Second identifier is main, name of method, main, name of method, method
8:10 Third identifier is string, string So test is the first one, main is the second String is the third because string is predefined the Java class name. Are you getting it's a name name of a class only that's why string fourth one a rgs name of the array. Okay next up fifth one x name of variable are you getting a name in Java program? is by default considered as what? identifier. Any explanation is required or not? The name itself in Java program by default considered as identifier. Take this example. Example and highlight how many identifiers are there in this program. Class
8:57 test public static void main class test public static void main string array asks. Next index is equal to 10. x is equal to 10. x is equal to 10. Test main string arc select. Completed right?
9:48 clear for all of you right? this one now next one okay sir while defining identifiers compulsor we should follow certain rules and regulations best example assume that you have one kid do you have the kids? no soon okay Assume you have one kid. You have to name your kid. You have to name your kid. Compulsory we should follow certain rules and regulations. Okay compulsory we should follow certain rules and regulations. Like your kid
10:33 name may be your ancestor name or maybe God name or God's name. It's nothing but like God name we can keep. So this type of sentiments usually we are going to follow. Are you going to keep your kid name as a dog? Then the kid is going to get left and right once he grows. So are you going to keep your kid name as a cat or something like? No. Compulsory while defining names we should follow certain rules and regulations. It's a mandatory. So while defining Java names also, while defining Java identifiers also There are some rules we have to follow such type of identifiers are by default considered as what? Valid identifiers, right? Are you getting? So what
11:19 rules we have to follow while defining identifiers? Compulsor you people should have clarity. Okay, keep supporting. Rules for, rules for defining, rules for defining, define Java identifiers. Rules for defining Java identifiers. Java identifiers Rules for defining Java identifiers Identifiers Now the first rule, take a bit special care What is the first rule here is observe Sir here in Java identifiers we cover several Which characters we can use Sir can I use alphabet symbol, is it
12:07 possible or not? Yes, so small lowercase letter, uppercase letter 0 to 9 we can use, next dollar symbol we can use Underscore symbol we can use The only allowed characters in Java identifiers are only these are things By mistake if you are using any other immediately compile time error by default you are going to get Are you getting rule number one The only allowed characters in Java identifiers are alphabet symbols or digit dollar underscore by mistake if you are using any other immediately compile the method you are going to get sir just observe total underscore number is it valid identifier or not total underscore number valid because I am using these symbols only no
12:56 problem at all sir total as a symbol is it valid or invalid Invalid because as a symbol we can't use it is not in allowed list characters right that's why So this one is nothing but invalid. Are you getting? Sir which characters are allowed in Java identifiers? Compulsor you people should have clarity right okay at first role The only allowed characters The only allowed characters The only allowed characters characters In Java identifiers are The only allowed characters in Java identifiers
13:42 are Take these things A to Z 0 to 9 If we are using any other character we will get compile time error. If we are using any other character we will get compile time error. we will get compile time, error,
14:32 error, example total underscore number total underscore number total underscore number total underscore number next to total ashe symbol total underscore number total ashe symbol like first one is the valid end but second one is invalid right Next, second rule. Okay, in most of the languages this rule is there. Sir, total 1, 2, 3. Is it valid or not? Total 1, 2, 3. Valid, valid. No problem at all. 1, 2, 3 total. Is it valid or invalid? This one is
15:20 invalid, compiled by metadata. Right? Because identifier should not start with the digit. Are you getting this rule is applicable even in C language or C++ everywhere right okay this rule is there that's why so identifiers should not start with digit okay this is so the first one is the valid second one is invalid at this point second identifiers identifiers Kant starts with digit. Take that example. Total 1,2,3.
16:07 Total 1,2,3. Valid. But 1,2,3 total. Total 1,2,3. Valid. But 1,2,3 total. Itself is valid or invalid? Invalid. 1,2,3 total. Invalid. Right. Next. Sir can you tell is it valid or invalid? Just observe this one Sir I am taking class test Here, int number is equal to 10 int number is equal to 20
16:52 int number is equal to 30 Inter number is equal to 30 like. Is it valid or not? Sir, here lower case, but here first letter is upper case, but here all are upper case. Java identifiers are case sensitive. Okay, so lower case uppercase there is a difference either of course Java language itself is considered as case-sensitive programming language. Are you getting that Java identifiers are case-sensitive Java language itself treated as case-sensitive language right now observe here we can use the word we can differentiate we can differentiate with respect to case we can
17:37 differentiate with respect to case is it clear right okay at this point Java identifiers are case sensitive. Of course Java language itself is treated as. case sensitive programming language of course java language itself is treated as case sensitive programming language java language
18:23 itself is treated as case sensitive programming language case sensitive programming language case sensitive programming language language that's all are getting so add this example class test Inter number is equal to 10 Inter capital number is equal to 10 Take that clearly Inter number is equal to 10 Inter capital number All are we can differentiate with respect to case We can we can differentiate with respect to case anyway, right?
19:14 completed I hope. Okay. Now, so this is the third, third rule. Right. Fourth one. Okay. Sir, can you tell in Java identifier, max, how many characters are allowed? Maximum, maximum. How many characters are allowed? Thirty two or 64? Max Max, how many characters are relevant? 32 or 64? Or 64 or 128? 64
20:04 or 128? 128 or 256? 256 or 512? Make sure there is no length limit for Java identifiers There is no limit on length of identifier. If you want you can take one crore length identifier also. But is it good programming practice or not we will decide. But there is no length limit for Java identifiers. Best example. Just observe this one. Here my requirement is just I am taking int xxxxxx like. Is nothing but a big identifier I am taking. xxxxxxx next yyyyy Like I am taking And then we can go for Z Z Z Z Like I am taking Right Okay this is Sir is equal to Then I am taking
20:53 Okay this is Now let me keep word wrapping anyway Sir wonderful beautiful identifier is nothing but like Sir is it valid or invalid Perfectly valid No problem at all Perfectly valid Sir let me let me compile GearJSubser JavaC JavaC Test.Java Value no problem at all Suppose assume assume I want to print the value of this variable then the cinema is going to start have you observed system dot out dot println off okay luckily we have copy paste option is there okay so here from here to here I'm taking luckily we have here just observed brah next this is
21:40 semicolon now observe What is the output by default you are going to get here is? Yes, pass. The code compiles fine. Then the answer is 10 by default. Are you getting? Now I called one expert programmer. I wrote one beautiful program. Can you please have a look on my program like? If I can show this program to any person, I'm sure that person is going to give left and right. Because, so how much lengthy code? Sir, in this lengthy program, what thing I'm doing? Yes, I declared one variable. Just I am trying to print, beyond that nothing. That's why. So highly recommended, highly recommended this type of coding is nothing but worst kind of programming practice. Are you getting right? So even though there is no length limit but not recommended to take two lengthy identifiers because the readability of the code is going to
22:26 be down. Is it clear right? Add. There is no length limit. There is no length limit. There is no length limit for Java identifiers. There is no length limit for Java identifiers But it is not recommended to take two lengthy identifiers Not recommended to take two lengthy identifiers. Not recommended to take two
23:11 lengthy identifiers. Two lengthy identifiers. That's all. Are you able to understand right? So this is another point what you people should aware. Now next one here see. Sir index is equal to 10. Is it valid or not? Int x is equal to 10. Valid or not? Value Int if is equal to 20. Valid or not? Invalued. Because what is the reason? If is a reserved word in Java. Are you getting it? If is a reserved word in Java or keyword you can use. Reserved word in Java. If is nothing but there is some meaning is there. How you can use if for your identification? Reserved words we
24:01 can't use as identifier by mistake if you are using compile time error by default you are going to get is it clear for all of your head? We can't use We can't use Reserved words as identifiers We can't use Reserved words as identifiers We can't use reserved words as identifiers Reserved words as identifiers, identifiers. Example add, int x is equal to 10 int x is equal to 10 int if is equal to 20 int x is equal to 10 int if is equal to 20 So the first one
24:52 is it valid or not? Valid. But second one invalid Because we are trying to use a reserved word as identifier. That's why the problem is coming We can't use reserved words as identifiers, right? Kena, are you able to understand right? Now the next terminology, now make sure you people should have clear clarity, right? Now the next terminology Here I'm taking class test class test Public static void main method String array asks Class test Public static void main String array asks Now Int Int String is equal
25:41 to 888 Int String is equal to 888 System.out.printl of String S-O-P of String Sir, value of string is nothing but, triple eight. S.O.P of string. Similarly, int runnable is equal to triple nine. S.O.P of runnable. S.O.P of runnable. Sir, can you tell what is the output by default you are going to get? S.O.P of runnable. What is the output? Sir, Inter string is equal to triple eight SOP of string Inter runnable is equal to triple nine SOP of runnable Can I use the term? In
26:29 the first case we will get triple eight In the second case we will get triple nine Correct or not? You have to decide Is it valid or invalid? Hundred percent PAKKA invalid Are you getting? Because What about string or not? String is? Pre-defined class name Intrafic is nothing more? Pre-defined Pre-defined interface name. Are you getting runable is nothing but pre-defined interface name? Now make sure What is the last point we covered? Can you please read? We can't use We can't use reserved words as identifiers. Right. Now my question is Who told to you these are reserved words? It is the pre-defined java class name? It is the pre-defined interface name? 100% pakka Perfectly valid. The answer we
27:16 are going to get is 388 followed by 39918. Don't keep any doubt in that. Okay? Here see Let me run this code. Here, just observe. I am taking int string. int string is equal to 888. Are you getting int string is equal to 888? System.out.println string I am taking. S-O-P of string. Have you observed right? int string is equal to 888 S-O-P of string. Now make sure. Why string is coming in the red color? Because it's a classroom. Now let me run this code. Sir the code compiles fine. What the answer by default you are going to get? Thripple 8 is the answer. Valid or not? Yes. Similarly int
28:02 runnable Runnable is equal to Thripple 9. Next S.O.P. of runnable like this I am taking S.O.P. of runnable. Now the code compile what the answer by default you are going to get is nothing but Thripple 9. Any explanation is required or not? All predefined Java class names and the interface names happily we can use as identifiers no problem at all Now my question is is it recommended or not recommended? Not recommended Worst kind of programming practice because unnecessary readability of the code is going to be down and we are creating confusion Okay this is add Yeah all predefined last one 61 I hope all predefined all predefined Java class names
28:51 and interface names all predefined Java class names and interface names all predefined Java class names and interface names and interface names names we can use as identifiers all predefined Java class names and interface names we can use as identifiers, identifiers. So, here's an example. Example. Class test. Public static void means
29:38 inter-string is equal to 8884P of string. So, the first one is the value. Inter-runable is equal to 9884P of runable. in the Renable is equal to 999 S4P of Renable. Sir, is it a valid or invalid? So, the first one is a valid, even second one also. Valid, no problem at all. Are you getting the point right? Okay? Now add the theory. Even though Even though it is valid Even though it is
30:26 valid Even though it is valid Even though it is valid But it is not a good programming practice Even though it is valid but it is not a good programming practice But it is not a good programming practice Not a good programming practice because Because, because it reduces, because it reduces readability, because it reduces readability, readability and creates confusion. Because it reduces readability and creates confusion. Reduces readability and creates confusion. Okay, that's all. Sir,
31:13 total, how many rules we covered? Six rules. So, can you please spell out what the first rule? The only allowed characters in Java identifiers are alphabet symbols digits $ underscore. Next identifier should not start with digit. Next third one, identifiers are case sensitive. Next there is no length limit for Java identifiers. We can't use reserved words as identifiers. All predefined Java class names and interface names happily we can use as identifiers. Sir from this discussion what is the possibility to ask the bit? Just I will give list in the which are valid Java identifiers and which are not you have to decide. Okay add question number. Add a bit style. Which of the following? Which of the following? Which of the following
32:03 are? Which of the following are? Valid Java identifiers. Which of the following are? Valid Java identifiers. which of the following are valid java identifiers identifiers identifiers okay now listen sir i am taking total underscore number total underscore number next total as a symbol next one two three total or total one two three total one two three next cash cash next underscore dollar underscore dollar underscore dollar
32:50 underscore all get rate hands next java to share java to share next sir here next integer next int next int Integer int int like that's all. Sir can you tell which are valid identifiers and which are not? First one valid. Second one invalid because as symbol we can't use. Third one invalid because identifier should not start with digit. Fourth one valid no problem. Fifth one valid. Sixth one valid. Have you observed I am not
33:40 doing any mistake. Next, Invalid because at the red symbol we can't use Next, this one Valid, no problem at all, alphanumeric characters you can use Next, Integer All predefined Java class names and interface name happily we can use as identifier, no problem Next, is it valid or no? Small Int is a reserved word but Captain Int is not reserved word, that's why this one is valid but last one, Invalid Are you getting right? Maybe a chance to ask. Which of the following are valid identifiers you have to fill? Okay, take all these things. Take, take.
34:59 total underscore number total ash 1,2,3 total total 1,2,3 all at the right hands java 2 share integer int int integer int int like I hope is clear for all of you right any explanation is required okay make sure next one next
35:50 so that's all this is about identifier's concept what we have now keep submitting reserved words Reserved. Reserved words Reserved words Next sub topic. Reserved words Sir here do you know In Java So in any language, need not be Java Maybe normal speaking language or programming language In any language Some words are reserved To represent some meaning or functionality Best example Let me consider our English language only English English language Have you observed? There are some words which are reserved To represent some meaning or functionality Best
36:38 example Here is Here cat Reserved to represent one type of animal Animal Dog Reserved to represent one type of animal Next apple This word reserved To represent one type of fruit, fruit Sir, eat This word reserved to represent one type of action, action Okay, same our favorite action sleep, you're getting So dot dot dot like Sir, in any language, whether it is normal, normal programming language or general speaking language Programming language or normal language, normal speaking language Some words are reserved to represent some meaning or functionality
37:25 Such type of words are nothing but what? Reserved words Sir, so in English crores of reserved words are there So if you consider dictionary Oxford is nothing but this much size dictionary also you can see But Java language is a small Chota programming language Are you getting? Here how many reserved words are there in English? Crores, crores But in Java How many reserved words are there? Just 53 Are you getting? Just 53 reserved words are there not crores A small short programming language is not Java right? So all these 53 reserved words you should aware Are you able to understand? Okay In
38:10 Java In Java In Java Some words are reserved In Java some words are reserved Some words are reserved To represent some meaning or functionality Such type of words are called Reserved words Such type of words are called reserved words.
39:00 So, do you know in Java how many reserved words are there? All these reserved words, compulsory you people should have clarity. Now just observe. How many reserved words are there in Java? total 53 reserved words are there. Don't write legend. Total how many are there? 53. In the...so here 50 keywords are there. How many are there? 50 keywords are there. And reserved letter also. Reserved letter also. Okay. 3 are there. Then immediately you may ask Sir what is the
39:47 difference between keyword and reserved word? If the reserved word associated with functionality that is called keyword If the reserved word only to represent some value not functionality then reserved letteral For so many reserved letterals are there? Three right? Which is three? If you want you can consider true Do you know true is a reserved word to represent one boolean value There is no functionality associated with true. True. False. True, false. Null. Null. These three are reserved laterals. Next, how many keywords are there? 50. In that 50, 48
40:35 are used keywords. And now, used keywords, how many are there? 48. Unused keywords, how many are there? Unuser keywords, how many are there? Is an Athema tattoo. Okay? Which two are unused keywords in Java? Go to under C-O-N-S-T Go to under C-O-N-S-T or unused. We can't use but these are keywords only. But user keywords how many are there? If, else, if, else, switch dot dot dot dot like. Are you getting? So compulsory for the exam safe All 53 reserved words you people should aware. It's easy. Nothing there. We list out all these 53. First take this diagram.
41:26 Reserved words 53 and keywords 50. User keywords 48. User keywords 48. Unused keywords 2. User keyword 48, Unuser keyword 2. Take, take,
42:13 clearly. So, reserved words, keywords, reserved letterals, user keywords, unused keywords. Next, how many reserved letterals are there? True, false, null. True false null null. True, false, null. Like this. The exam says all 53 reserved words compulsory you people should aware. All 53 reserved words.
43:03 I hope. Completed right? These are the reserved words present in Java. Now let me spell out all these things. Now keep subheading. Keep supporting. Okay. Keywords for data types. Keywords. Keywords for data types. Keywords for data types. Keywords for data types. Data types. Sir, for data types, how many keywords are there? Okay. Do you know? Just, I will spell out here. Just observe. Bite. Shark. Car, bite short int int long
43:51 bite short int long float double float double boolean car how many are there? 8 are there bite short int long float double boolean car add all these things Keywords for data types. Byte, short, int, long, float, double, boolean, care. Boolean, boolean, care. Care. Boolean, care. Completed, right?
44:40 Next one. Next point. Add keywords for Keywords for flow control. Keywords for flow, flow control. Sir how many keywords are there for flow control? If, if, else, if, else, switch, if else switch, within the switch case default, within the switch case default. Next, while, do, Do and while. Do while. For, for, break, continue, return. Break, continue, return.
45:28 Sir, can you, have you observed? How many are there? Huh? Huh? 11. 11 are there. Okay. Add. If else switch, default while do for break continue return for break continue return break continue return like this can are you able to understand right Okay, next one.
46:18 Okay, this is the first. Anyway, next up. Keywords for, keywords for modifiers. Keywords for modifiers. Modifiers. So, how many modifiers are there in Java? Twelve modifiers. But default we are not going to write. That's why your how many should come. Okay, public. Can you spell out? Private. Public, private, protected. If you are not writing anything, it is the default. We can't write. Default. Next. Static. Final. Static final. Abstract. Synchronized. Synchronized or nized? Synchronized.
47:05 Native. Synchronized, native. Next. Strict FAP. Do you know? This new keyword came In the 1.2 version. Strictly FOP. Next and after that, Transient. Transient Volatile. Transient Volatile is nothing but like. Sir, how many are there? Can you please cross check? 11. Because with default 12. 11 are there. Keywords for modifiers. Modifiers are related keywords.
47:54 Completed I hope. Next one. Keywords for modifiers. Next up. Keywords for... Keywords for... Exception handling. Keywords for exception handling. Keywords for exception handling. Handling. Can you spell out? How many keywords are there for exception handling? Sir.
48:40 Can you spell out? Try... Catch... Finally... Throw... Throws... and better to use assert because it is also related to exceptional learning only debugging purpose 1.4 version it is a new thing which came in the 1.4 version right do you know how many came? 6 6 next one Alright catch finally throw throws yes sir.
49:31 Okay now keep subbing. Class related keywords. Class related keywords. Class related keywords. Sir which keywords are class related keywords. Okay so your legend class itself is a keyword. Intraface itself is a keyword. Class interface. Next, extends is a keyword. Implements is a keyword. Implements, extends, implements. Next, package itself is a keyword. Import, import or imports? Import itself is a keyword. That's why total. How many keywords are there? Six.
50:18 Six keywords are there. Make sure. Okay, like add. Enum is a separate keyword, I will discuss. Class, Intraphase Extends Implements Package Imports. Import. These are the class related keywords. Next up, Object related keywords. Object, object related keywords. Sir what are various object related keywords or? Neo itself is a keyword. Object related keyword. Next. Instance of. Sir O is the small or capital? Instance
51:09 of. Make sure. O is the small. Small o. Instance of. So for under this. So for under this. This. Do you know how many modifiers are there? Is nothing about soper? New instance of soper this. That's all. Only four. New instance of soper this. So, do you know delete keyword is not there in Java because destruction of useless objects is the responsibility of garbage collector. Delete. Delete keyword is not there. Next one. Keep subheading. Keep subheading. Why it return type keyword? Why it return type keyword?
51:59 Why it return type keyword? Why it return type keyword? Sir, can you tell? Why it return type keyword? Okay, here legend. Legend is at this point. Well, why it return type keyword? If a method won't return anything, that method we should declare with the why it return type. Do you know? If I can take like this, public M1, is it valid or invalid? Invalid. Compacty M1 are saying return type is missing. But in C long way, return type is optional and the default return type is, inter return type. Int, int written type. If you want to return int, you are not required to specify anything but in Java, written type is mandatory. If a method won't
52:49 return anything, that method we have to declare with what? Void. At this point. At the point where. In Java, in Java, written type is mandatory. In Java, written type is mandatory. Return type is mandatory. If a method won't return anything, then we have to declare that method with the. Why
53:36 it return type? We have to declare that method with the void written type We have to declare that method with the void written type written type, okay, that's all next paragraph, but in C language But in C language written type is But in C language written type is optional, but in C C language written type is optional, written type is optional Under default, return type is But in C language, return type is optional. Under default, return type is Under default, default return type is Now, what's the default return type? Default return type is int But in C language, return
54:23 type is optional. Under default return type is int, int, int, int. That's all. Are you getting? Next. So, keep supporting unused keywords. Unuser keywords Unuser keywords, keywords Unuser keywords Sir can you tell how many unuser keywords are there in Java? Okay? How many? How many are there? Just don't write legend Go to C O N G E S T 1 minute, 1 minute Here just there are two unuser keywords are there, don't write legend There are two Now first one go to Okay? Here do you know in the C language go to keyword is there. But usage
55:10 of go to created several problems in whole languages. Usage of go to created several problems in whole languages. That's why some people banned this keyword in Java. Because you are not allowed to use this keyword. Like some people banned this keyword in Java. Right. Okay. This is it. Next second one. C-O-N-S-T. Can you tell what the purpose of C-O-N-S-T? Ah. For the purpose of to define constant already final keyword is there. So use final instead of even state. That's why these two keywords are not allowed. By mistake if you are trying to use these two immediately compile the method you are going to get. First one keep somebody go to. First one go to go to. First one go to.
55:59 Usage of go to. Usage of go to. Go to. created several problems in old languages and hence some people S-U-N son. Some people banned B-A-N, banned. Some people banned this keyword in Java. Some people banned this keyword in Java.
56:47 Some people banned this keyword in Java. In Java. Some people banned this keyword in Java. That's all. This is about go-to. Now second one. C-O-N-S-T C-O-N-S-T Use a final use a final use a final final instead of use a final instead of c o n s t use a final instead of c o n s t use a final final instead of c o n s t that's all. Are you getting? So but go to under c o n s t these are unused keywords by mistake if
57:32 you are trying to use immediately compile time error we will get it. Take a note note Go to and C-O-N-S-T Go to and C-O-N-S-T or unused keywords and if we are trying to use And if we are trying to use and if we are trying to use trying to use We will get compile time error. We will get compile time error We will get compile time error error Okay, that's all this is about go to and
58:22 c-o-n-s-t. Are you getting right? Next keep supporting Reserved literals Reserved literals Reserved literals, literals Reserved literals, do you know? Here don't write legend How many reserved literals are there? True, False, Null, don't write legend, legend this one Three, three reserved literals are there Sir, here observe True, False, do you know? These are values for, values for Boolean data type, values for boolean data type. Okay? This is same. Next, NULL. NULL is
59:09 default value. Default value for object reference. Default value for object reference. Okay? Take this one. TRUE, FALSE. Value is for boolean data type. NULL. NULL. Default value for object reference. NULL. Default value for object reference. For object reference. For object reference. That's all. Default value for object reference. That's it. Completed, right? Okay.
59:58 Next up. Default value for object, object reference, right? Okay? Now true, false, null itself is the clear for all of your right. So next one, make sure Enum keyword. Keep subiting Enum Enum keyword Enum keyword So do you know within bracket, in which version this one came? Enum, Enum 1.5 version Enum keyword within bracket 1.5 version Sir can you tell when we should go for Enum? If we want to define a group of named constant then we can go for Enum add We can use Enum We can use Enum to define
1:00:48 We can use Enum to define a group of named constants We can use Enum to define a group of named constants We can use Enum to define a group of Nimud constants. Nimud, Nimud constants. We can use Enum to define a group of Nimud constants. Nimud, Nimud constants. Constants. Okay? Example, do you know, in the Enum concept I will explain. Just Enum month. Sir, can you tell, what are the allowed values for month? Jaan, Peb, dot dot dot, December like. on pep dot dot dot d e c like this we have next time enum enum
1:01:37 bear sir can you tell what are the allowed values for the bear ayo k f k o r c f o dot dot dot right okay add examples enum mant enum mant Next, Enum Beer. John Peb dot dot dot EC. Enum Beer. K-F-K-O-R-C-F-O.
1:02:25 Okay, that's all. Sir can you please crouch all the 53 came count wise can you please crouch 8 plus 11 plus 11 22 plus 8 30 42 46 47 49 50 53 that's all all the 53 are there so on the board now by seeing all these 53 there are some common conclusions we can conclude keep somebody conclusions Conclusions Conclusions Sir can you tell Among all 53 Are you seeing any some common property? Hmm All 53 reserved words contain Only alphabet
1:03:15 symbols Correct or not? Are you seeing any very special characters? No Next all 53 reserved words contain Only lower case alphabet symbol Are you getting? You can't see anywhere uppercase character Best example, instance of Do you know? O is the small or capital? Small Strict F of P F is the small or capital? Small only Everywhere So it should contain only lowercase alphabet Null, Null Do you know? Most of the people are going to write Null means N-U-L-L or N-U-L-L No such type of terminology N should be in the lowercase right, okay? Add First conclusion All 53 reserved words in Java All 53
1:04:03 reserved words in Java All 53 reserved words in Java contains All 53 reserved words in Java contains only contains only lowercase alphabet symbols contains only lowercase alphabet symbols Sometimes only lower case alphabet symbols. Symbols. Okay? One thing. Next or second. Do you know in Java new keyword is there? But delete keyword is there in Java? No. Because destruction of useless objects is the responsibility of garbage collector. Second one. In Java, in Java we have only new keyword.
1:04:52 In Java we have only a new, new keyword. In Java we have only a new, new keyword. And there is no delete keyword in Java. And there is no delete keyword. And there is no delete keyword because, and there is no delete keyword because, because, because destruction of useless objects, because destruction of useless objects, destruction of useless objects is the responsibility destruction of useless objects is the responsibility of destruction of useless objects is the responsibility of responsibility of of garbage collector destruction of useless objects is the responsibility of garbage collector of garbage garbage
1:05:43 collector right are you getting the point okay this is next to third one third conclusion three Third one, legend. Legend very very carefully about this point, right? Third one. Here, which keywords are new in Java? There are some new keywords are there in Java which are new. One is strict FOP. This keyword came in which version? 1.2 version. A new keyword 1.2. Next, this keyword came in which version? 1.4 version. Next, enum. This keyword came in which version? 1.5 version. These are three
1:06:29 are new keywords in Java. The following are new keywords in Java. new keywords in Java. This is one one thing what you people should aware. Strict FOP came in the 1.2 version. Yassarta came in 1.4 version. Yinam came in 1.5 version. 1.5 version. Okay. Now next point make make sure you people should aware clearly.
1:07:18 Sir yeah. strict FOP but not strict FOP but not strict FOP. First one. Next. In instance of Either small or Captain? Small but not but not instance of but not instance of Next, Synchronized or Nized? Synchronized
1:08:07 but not synchronized Are you getting Synchronized but not Synchronized Next, Extend or Extends? Extends but not extend. Next, implement or implement? Implements but not implement. Import or imports? Import but not imports. Import but not imports. Next, here do you know, c-o-n-s-t,
1:08:54 c-o-n-s-t but not constant. Here while spelling, while pronouncing we can use constant but c-o-n-s-t but not c-o-n-s-t-a-n-t. Are you getting? So make sure, take all these things, small, small variations you have to identify.
1:09:54 completed right but not strict FOP instance of but not instance of synchronized but not synchronized extends but not extend extends but not extend but not extend next implements but not implement Import but not imports. Employment but not imports.
1:10:40 Take all. Have you completed right? Next. You know from this total discussion. So what possibility to ask the question for the exam. So let me convert into British style. Take a bit. Which of the following list contains only Java Reserved Words? Java Reserved Words
1:11:29 Can I spell out Which list contains only Java Reserved Words? Take this one New Delete First one New Delete First List Second Go to CON Go to Constant Break Click continue, return exit. Next up final, finally, finalize.
1:12:17 Finally finally finalize. Notify all. Next, Implements, Extends, Imports. Implements, Extends, Imports.
1:13:10 update your book
1:14:01 but not C1, S, A, N, T Third one Exit is a method, not reserved word Fourth one Finalize is a method Fifth one Throne, such type of terminology, not there Next, notify, notify all, these are methods but not keywords, but not reserved words Next one Implements, extends, imports, import but not imports Next, size of, not there in Java Instance of is there but size of is not there Instance of O is the capital, F is the capital Next of bite, short, int, I capital That's why no list contains, so none of the above is the correct answer Okay, none
1:14:46 of the above If you want just to observe, search which are various violations right Now you can able to see These are those are not reserved. What's delete is not there? C-O-N-S-T-A-N-T Exit to finalize throne Notify notify all imports size of instance of like these things so which list contain Java reserved about sir is nothing but no list. Okay, this is so which one is the correct answer. None of the right. Okay, like next second one
1:15:32 Java Reserved Votes Which of the following are Java Reserved Votes Java Reserved Votes Public Static Void Public Static Void Main String Arks Public Static Void String Arks Can you tell among these Public is a valid, static is a valid, void is a valid But the main is just name of the method not reserved word String is a name of predefined class, ox is a name of variable That's why, first three Public, static,
1:16:20 void If you want you can see which things came in blue color Public, static, void, that's all String came in red color because it's a predefined class, that's it So these are data types, I mean these are reserved words, whatever there, I hope. But for the exam, say, all the 53 reserved words you people should memorize. Okay, this is nothing easy, easy way. So because we listed directly on the board, okay, that's all.
