Java/C2/Relational-Operations/Gujarati
From Script | Spoken-Tutorial
Time' | Narration |
00:01 | Welcome to the spoken tutorial on Relational Operators in Java. |
00:07 | In this tutorial, we will learn about the
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00:09 | the boolean data type |
00:10 | Relational operators and |
00:12 | how to compare data using Relational operators.
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00:17 | For this tutorial we are using
Ubuntu 11.10, JDK 1.6 and Eclipse 3.7 |
00:26 | To follow this tutorial, you must have knowledge of data types in Java
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00:31 | If not, for relevant tutorials, please visit our website as shown. |
00:39 | Relational operators are used to check for conditions.
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00:43 | Their output is a variable of boolean data type
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00:48 | A boolean data type is of size 1 bit
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00:51 | It stores only two values.
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00:54 | True or False.
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00:56 | True is the output when the condition is true.
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00:59 | False is the output if the condition is not true. |
01:06 | Here is a list of the Relational operators available.
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01:10 | * greater than |
01:12 | * less than |
01:13 | * equal to |
00:14 | * greater than or equal to |
01:15 | * less than or equal to |
01:17 | * not equal to |
01:19 | We shall look into each of them in detail. |
01:22 | Switch to Eclipse. |
01:27 | Here we have the Eclipse IDE and the skeleton required for the rest of the code.
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01:33 | I have created a class BooleanDemo and added the Main method.
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01:38 | Now let us add some expressions. |
01:41 | Type boolean b ;
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01:47 | The keyword boolean declares the data type of the variable b as boolean.
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01:53 | We shall store the result of our condition in b. |
01:5 | We shall define a variable weight and check for a condition using that variable.
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02:05 | int weight equal to 45;
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02:13 | We shall check if the value in weight is greater than 40.
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02:18 | b equal to weight greater than 40;
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02:28 | This statement says check if the value of variable is greater than 40 and store the result in b;
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02:37 | Now Let us print the value of b.
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02:41 | System dot out dot println(b);
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02:49 | Save and Run. |
02:59 | As we can see, the output is True. |
03:02 | Let us see what happens if the value is less than 40.
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03:07 | Change weight to 30.
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03:12 | Save and run |
03:20 | We can see that the output is False as expected. |
03:24 | This way, the greater than symbol is used to check if one value is greater than the other.
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03:30 | Similarly, less than symbol is used to check if one value is less than the other. |
03:37 | let us change thegreater than to less than symbol.
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03:43 | So We are checking if the value of weight is less than 40.
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03:48 | Save Run |
03:56 | As we can see, the output is True as expected.
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04:01 | Let us change the value of weight to 45 and see the output.
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04:09 | Save and Run. |
04:16 | We see that we get a False because the condition,
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04:21 | weight less than 40 is not true.
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04:25 | Now let us see how to check if a value is equal to another. |
04:31 | To do that, we use two equal to symbols.
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04:35 | change less than symbol to double equal to.
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04:41 | Save and Run |
04:48 | As we can see, the output is False because the value of weight is not equal to 40. |
04:55 | Now let us change the weight to 40 and see the output. |
05:01 | Save and Run. |
05:08 | As we can see, the output is True
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05:12 | This way, Double equal to is used for checking equality.
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05:16 | Please be careful because, often people use a single equal to symbol for checking equality.
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05:22 | And this gives unnecessary errors. |
05:26 | Next we'll see how to check for less than or equal to.
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05:30 | To do that, we will use a less than symbol followed by an equal to symbol.
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05:35 | change the double equal to to less than equal to.
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05:42 | Save and Run. |
05:50 | the output is True as expected.
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05:53 | Now let us change the value of weight to see if the less than check is performed. |
05:59 | Change 40 to 30. |
06:04 | Save and Run.
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06:14 | We see, that although the weight is not equal to 40 we get the output as True because it is less than 40.
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06:22 | Let us see what happens if the value of weight is greater than 40. |
06:274 | Let say 50. Save and Run. |
06:39 | As we can see, the output is False because the value of weight is not equal to 40.
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06:44 | And it also not less than 40. |
06:48 | Similarly we use a greater than symbol followed by an equal to symbol for checking greater than or equal to.
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06:55 | Let us try it. |
06:57 | Change less than equal to to greater than equal to
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07:04 | Save and Run.
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07:10 | As we can see, the output is true because weight is greater than 40 |
07: 16 | Let us change weight to a value less than 40. Lets say 30.
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07:25 | Save and Run. |
07:32 | We get a false because the value of weight is not greater than 40 and also not equal to 40. |
07:39 | Next, we’ll see how to check for not equal to
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07:46 | It is done by using an exclamation mark followed by an equal to symbol.
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07:53 | Change greater than to exclamation
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07:59 | So this statement says check if the value of weight is not equal to 40 and store the result in b
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08:08 | Save and Run |
08:16 | As we can see, the output is true because the values of weight is not equal to 40. |
08:23 | Let us change the weight to 40 and see the output. |
08:28 | Change 30to 40. |
08:31 | Save. Run. |
08:38 | We get a false because the condition weight not equal to 40 is false. |
08:45 | The not equal to condition can be thought of as opposite of equal to condition. |
08:50 | This is how we use the various relational operators to compare data in Java. |
08:58 | This brings us to the end of this tutorial.
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09:01 | In this tutorial we have learnt, about the boolean data type |
09:06 | The relational operators and |
09:08 | how to use relational operators to compare two values |
09:13 | As an assignment for this tutorial, find out if the two expressions shown are equivalent? |
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10:05 | This tutorial has been contributed by TalentSprint. Thanks for joining.
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