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valueOf() and parseXxx() for Character and Boolean wrapper classes - sounds like erratum in K&B

 
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According to K&B (Page No. 243 table) :

1) valueOf() method takes the 'first argument' as only String representation and doesn't work for Character wrapper class.

2) parseXxx() method doesn't work for Boolean wrapper class

But, according to my tests :

1) valueOf() method is working for Character wrapper class with an argument taken in character representation i.e for instance, Character.valueOf('a')

2) parseXxx() method is working for Boolean wrapper class i.e for instance, Boolean.parseBoolean("True")

Please comment on this ......... what is your Opinion on these ?
 
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Don't you check it with API?
 
Prashanth Patha
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While executing practice programs , i came to know that . Did you ever experience the same? Just for confirmation , i posted this topic and i did not check API till now.
 
Abimaran Kugathasan
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You should do that. Because, there may be some errors/versions in the K & B's book,
 
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Hi Prashanth,

just re-reading page 241, I don't see that it says that 'valueOf' only takes a String argument. Looking at the API it takes several depending on the wrapper. For instance, Integer has 3 versions of valueOf:

static Integer valueOf(int i)
static Integer valueOf(String s)
static Integer valueOf(String s, int radix)

Looking at the Character API, there is:

static Character valueOf(char c)

Perhaps the exam (and therefore the book) is only interested in the valueOf method that takes a String.
 
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Please note that the table on p. 243 is presented as "Common Wrapper Conversion Methods" only, not as an exhaustive list of all conversion methods. The authors are trying to focus our attention on what is important for the exam.
 
Prashanth Patha
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Thank you all who replied to my topic.
 
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