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|| '''Time'''
|| '''Narration'''

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|00:01
|  Welcome to the Spoken Tutorial on '''Type Conversion in Java'''.

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|  00:06
|  In this tutorial, we learn:

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|  00:08
| How to convert data from one data type to another.
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|  00:13
|The two types of conversion, namely '''implicit''' and '''explicit conversion''' and
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|  00:18
|How to convert '''strings''' to numbers.

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|  00:23
|  For this tutorial we are using: 
'''Ubuntu v 11.10''',
'''JDK 1.6'''  and
'''Eclipse 3.7'''

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| 00:33
|  To follow this tutorial, you must have  knowledge of '''data types''' in Java.

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|  00:38
|If not, for relevant tutorials, please visit our website as shown.

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|  00:47
|   '''Type conversion''' means converting data from one data type to another.

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|  00:53
|Let us see how it it done. 

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|  00:55
|Switch to '''Eclipse'''.

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|  01:02
|  Here we have the 'Eclipse IDE' and the skeleton required for the rest of the code.

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|  01:07
|I have created a '''class''' '''TypeConversion''' and added the '''main method''' to it.

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|  01:13
|Now let us create a few variables.

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|  01:19
| '''int a ''' equal to '''5;'''
'''float b;'''
 
'''b''' equal to '''a;'''

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|  01:33
|I have created two variables. '''a''' which is an integer and '''b''' which is a '''float'''.

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|  01:39
|I’m storing the integer value in a '''float variable'''.

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|  01:43
|Let us see what the float variable now contains.

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|'''System''' dot '''out''' dot  '''println(b);'''   

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|'''Save''' the file and '''run''' it.

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|  02:07
|  We can see that the '''integer 5''' has been converted to '''float 5.0'''

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|  02:13
|This type of conversion is called '''implicit conversion'''.

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|  02:17
|As the name goes,  the value is automatically converted to suit the data type.

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|  02:24
|Now let us convert '''float''' to an '''int''', using the same method.

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|   02:30
| Remove the '''5''',  '''float b''' equal to '''2.5f'''  and let us store 'b' in 'a' and print the value of 'a'. 
 
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|Save the file.

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| we see that there is an error.

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|  03:00
|The error message  reads- '''Type mismatch: cannot convert from float to int'''.

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|  03:06
|It means '''Implicit conversion''' is possible only from an '''int''' to a '''float''' but not the the other way.

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|  03:13
|To convert a '''float''' to an  '''int''' we have to use explicit conversion.

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|  03:17
|Let us see how to do so.

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| We do that by using an '''int''' in parentheses, before the variable.
 
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| This statement says the data in the variable 'b' has to be converted to '''int''' data type and stored in 'a'.

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| save and '''run''' the file. 

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|  03:51
| As we can see, the '''float''' value has been converted to '''int'''.

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|  03:56
| But to suit the data type, the data has been changed accordingly.

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|  04:01
| Explicit conversion can also be used to convert data from '''int''' to '''float'''.

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|  04:07
| Let us try the previous example.

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|   '''int a =5; float b; b = (float) a;''' 
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| '''System.out.println(b);'''
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| We are using '''Explicit conversion''' to convert integer to a ''' float'''.
 
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| '''Save'''  the file and '''Run''' it.

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|  we see that the '''int''' value has been converted to a '''float''' value. 

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|  04:58
| Let us  see what happens when we convert a '''character''' to an '''integer'''.

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| '''int a'''; '''char c ''' equal to in single quotes '''m''';
 
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|  05:24
| '''a''' equal to  '''(int) c;''' 

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| '''System''' dot '''out''' dot '''println(a);'''

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|  05:36
| We are converting the character 'm' to an '''integer''' and printing the value.
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|  05:43
| Let us '''save''' and '''run''' it. 

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|   As we can see, the output is 109 which is the ascii value of 'm'. 

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| It means when a '''char''' is converted to '''int''', its ascii value is stored.

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| Let us try this with a digit.

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|   '''char c =''' digit '''5''';  

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|  '''Save''' it and '''run''' it. 

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|  06:18
|  As we can see, the output is 53 which is the ascii value of the character ‘5’.

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|  06:24
| It is not the number 5.

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|  06:26
| To get the number, we have to use a '''string''' and convert it to an integer.

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|  06:31
| Now let us see how to do so.

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|  06:33
|  Clean up the '''main''' function. 

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|  06:38
| Type:

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|  06:40
|'''String sHeight''' meaning string form of Height equal to in double quotes 6  

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|'''int h''' equal to explicit conversion  '''int''' of '''sHeight'''  and 
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|'''System''' dot '''out''' dot  '''println(h)'''  '''Save''' the file. 

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|  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 there is an error
 
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| 07:37
|   and the error message reads: '''Cannot cast from String to int.''' 

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|  07:42
|This means, for converting strings, we cannot use implicit or explicit conversion.

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|  07:48
|It must be done by other methods. let us use them.

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| 07:58
|  Remove  '''int sHeight ''' and type  '''Integer''' dot ''parseInt'' sHeight''';
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|  08:21
|'''Save''' the file and '''run''' it. 

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|  08:29
|  we see that the value has been successfully converted to an integer.

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|  08:35
|To do this, we use the '''parseInt  method''' of the '''integer module'''. 

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|Now let us see what happens if there are more than one digits like "6543"
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| '''Save''' the file and '''run''' it.

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|   We see that again the '''string''' containing  the number has been successfully converted to an integer.
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|  09:03
|Now, let us see what happens if the '''string''' is a floating point number.
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|  09:10 
|Change "6543" to "65.43". So, we have a floating point number in a '''string''' and we are converting it to an integer.
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|  09:22
|'''Save''' the file, '''run''' it.
 
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|  09:31
|  We see that there is an error. This happens because we cannot convert a   '''string'''  which contains '''floating point number''' into an '''integer'''.

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|  09:41
| We have to convert it to  a '''float'''. Let us see how to do so.
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|First, data type should be '''float''',
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|second we will use '''Float. parseFloat'''.

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|We are using the '''parseFloat method''' of the '''float class''' to convert the string containing a floating point number into an actual floating point number.
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|  10:18
|'''Save''' the file, '''run''' it. We can  see that the string containing a '''floating point number'''  has been successfully converted  to a floating point number.
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|  10:33
|And this is how we do '''implicit''' and '''explicit conversion''' and how we convert '''strings''' to '''numbers'''.
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| This brings us to  the end of the tutorial. 

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|In this tutorial we have learnt: How to convert data from one type to another. 
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| 10:54
| What is meant by '''implicit''' and  '''explicit''' conversion. 
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| 10:57
| and How to '''convert strings to numbers'''.

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| 11:01
|  |As an assignment for this tutorial, read about the '''Integer.toString''' and '''Float.toString''' '''methods'''

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|  11:07
|and find out what do they do?

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|   11:14
| To know more about the 'Spoken Tutorial' project, watch the video available at the following link. 
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| 11:20
| It  summarizes the Spoken Tutorial project.

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|  11:23
|If you do not have good bandwidth, you can download and watch it.

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|     11:27
| The Spoken Tutorial Project Team. Conducts workshops using 'spoken tutorials'. 
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| 11:31
| Gives certificates to those who pass an online test. 
|-
|  11:34
|For more details, please write to '''contact AT spoken HYPHEN tutorial DOT org.'''

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|  11:40
|The 'Spoken Tutorial' Project is a part of the 'Talk to a Teacher' project.  
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|  11:44
|It is supported by the National Mission on Education through ICT, MHRD, Government of India. 
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|  11:50
|More information on this mission is available at the following link '''spoken HYPHEN tutorial DOT org SLASH NMEICT HYPHEN Intro'''.

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| 11:55
|  This tutorial has been contributed by '''TalentSprint'''. Thanks for joining.

|}