Java/C2/Primitive-type-conversions/English-timed
From Script | Spoken-Tutorial
| Time' | Narration |
| 00:01 | Welcome to the spoken tutorial on Type Conversion in Java. |
| 00:06 | In this tutorial, we learn: |
| 00:08 | * How to convert data from one data type to another. |
| 00:13 | * the two types of conversion, namely implicit and explicit conversion. And |
| 00:18 | * How to convert strings to numbers
|
| 00:23 | For this tutorial we are using
|
| 00:33 | To follow this tutorial, you must have knowledge of data types in Java.
|
| 00:38 | If not, for relevant tutorial please visit our website as shown |
| 00:47 | Type conversion means converting data from one data type to another.
|
| 00:53 | Let us see how it it done.
|
| 00:55 | Switch to Eclipse |
| 01:02 | Here we have the Eclipse IDE and the skeleton required for the rest of the code.
|
| 01:07 | I have created a class TypeConversion and added the main method to it.
|
| 01:13 | Now let us create a few variables. |
| 01:19 | int a equal to 5
float b b equal to a
|
| 01:33 | I have created two variables. a which is and integer and b which is a float.
|
| 01:39 | I’m storing the integer value in a float variable.
|
| 01:43 | Let us see what the float variable now contains.
|
| 01:48 | System dot out dot println b '
|
| 01:58 | Save the file and run it. |
| 02:07 | We can see that the integer 5 has been converted to float 5.0
|
| 02:13 | This type of conversion is called implicit conversion.
|
| 02:17 | As the name goes, the value is automatically converted to suit the data type.
|
| 02:24 | Now let us convert float to an int, using the same method. |
| 02:30 | Remove the 5 float b equal to 2.5f and let us store b in a and print the value of a . |
| 02:50 | Save the file.
|
| 02:56 | we see that there is an error.
|
| 03:00 | The error message reads, Type mismatch: cannot convert from float to int
|
| 03:06 | It means Implicit conversion is possible only from an int to a float but not the the other way.
|
| 03:13 | To convert a float to an int we have to use explicit conversion.
|
| 03:17 | Let us see how to do so. |
| 03:23 | We do that by using an int in parentheses, before the variable
|
| 03:34 | This statement says the data in the variable b has to be converted to int data type and stored in a. |
| 03:43 | save and run the file |
| 03:51 | As we can see, the float value has been converted to int.
|
| 03:56 | But to suit the data type, the data has been changed accordingly.
|
| 04:01 | Explicit conversion can also be used to convert data from int to float.
|
| 04:07 | Let us try the previous example. |
| 04:10 | int a =5, float b, b = float a |
| 04:32 | System.out.println(b); |
| 04:36 | We are using Explicit conversion to convert integer to a float |
| 04:42 | Save the file and Run it.
|
| 04:51 | we see that the int value has been converted to a float value
|
| 04:58 | Let us see what happens when we convert a character to an integer. |
| 05:06 | int a, char c equal to in single quotes 'm';
' |
| 05:24 | a equal to '(int) c |
| 05:32 | System dot out dot println ' a. |
| 05:36 | We are converting the character m to an integer and printing the value |
| 05:43 | Let us save and run it |
| 05:53 | As we can see, the output is 109 which the ascii value of m.
|
| 05:58 | It means when a char is converted to int, its ascii value is stored.
|
| 06:03 | Let us try this with a digit. |
| 06:06 | char c = digit 5 |
| 06:11 | Save it and run it |
| 06:18 | As we can see, the output is 53 which is the ascii value of the character ‘5’ |
| 06:24 | It is not the number 5.
|
| 06:26 | To get the number, we have to use a string and convert it to an integer.
|
| 06:31 | Now let us see how to do so. |
| 06:33 | Clean up the main function |
| 06:38 | type
|
| 06:40 | String sHeight string form of Height equal to in double quotes 6
|
| 06:58 | int h equal to explicit conversion to int of sHeight and |
| 07:11 | System dot out dot println h Save the file. |
| 07:27 | I’ve created a string variable with value 6 and i am trying to convert it to an integer but we see that their is an error
|
| 07:37 | And the error message reads Cannot cast from String to int.
|
| 07:42 | This means for converting strings, we cannot use implicit or explicit conversion.
|
| 07:48 | It must be done by other methods. let us use them |
| 07:58 | Remove int sHeight and type Integer dot parseInt sHeight '. |
| 08:21 | Save the file and run it
|
| 08:29 | we see that the value has been successfully converted to an integer. |
| 08:35 | To do this we use the parseInt method of the integer module. |
| 08:41 | Now let us see what happens if their are more than one digits like 6543 |
| 08:49 | Save the file and run it
|
| 08:55 | We see that again the string containing the number has been successfully converted to an integer |
| 09:03 | Now let us see what happens if the strings is a floating point number |
| 09:10 | Change 6543 to65.43.So we have a floating point number in the strings and we are converting it to an integer |
| 09:22 | Save the file run it.
|
| 09:31 | We see that their is an error This happens beacuse we cannot convert a string which contains floating point number to an integer
|
| 09:41 | We have to convert it to a float.Let us see how to do so; |
| 09:45 | First data type should be float, |
| 09:51 | Second we will use float . parsefloat |
| 10:07 | We are using the Parsefloat methods of the float class to convert the string containing a floating point number into an actual floating point number. |
| 10:18 | Save the file run it. We can see that the string containing a floating point number has been successfully converted to floating point number. |
| 10:33 | And this is how we do implicit and explicit conversion and How do we converts strings to numbers. |
| 10:45 | This brings us to the end of the tutorial. |
| 10:48 | In this tutorial we have learnt how to convert data from one type to another. |
| 10:54 | What is meant by implicit and explicit conversin |
| 10:57 | and How to convert strings to numbers. |
| 11:01 | As an assignment for this tutorial Read about the Integer.toString and Float.toString.
|
| 11:07 | And Find out What do they do? |
| 11:14 | To know more about the Spoken Tutorial project, watch the video available at the following link, |
| 11:20 | It summarises the spoken- tutorial project. |
| 11:23 | if you do not have good bandwidth, you can download and watch it |
| 11:27 | The Spoken Tutorial Project Team. Conducts workshops using spoken tutorials |
| 11:31 | Gives certificates for those who pass an online test. |
| 11:34 | For more details, please write to contact AT spoken HYPHEN tutorial DOT org. |
| 11:40 | The Spoken Tutorial Project is a part of the Talk to a Teacher project |
| 11:44 | It is supported by theNational Mission on Education through ICT, MHRD, Government of India. |
| 11:50 | More information on this Mission is available at the following link spoken HYPHEN tutorial DOT org SLASH NMEICT HYPHEN Intro |
| 11:55 | This tutorial has been contributed by TalentSprint. Thanks for joining.
|
Contributors and Content Editors
Gaurav, Kavita salve, PoojaMoolya, Priyacst, Sandhya.np14, Sneha