Why not compile java code phrase through

BufferedReader in = new BufferedReader(new FileReader(fileName));
  		
  		while ((String str = in.readLine())!=null) {
  			
  		}

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while ((String str = in.readLine ())! = null) in
executed first in.readLine () to get the results
then assign the result to str
The scope is str (String str = in.readLine ()) brackets, this bracketed value str
out of the brackets str be recycled . .

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  String str;
  		while (( str = in.readLine())!=null) {
  			
  		} 
  

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scope of local variables issues now

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code stickers multi-point , as well , the compiler does not pass error is which ? These two lines of code all given?
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+1
java is not defined more than once with the same name variable
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can only say that a long exposure , the statement or on the outside of the loop is good !
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grammatical problems while in the Shashi Hou can define things
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like if ((int a = 0) == 0) {} this syntax is wrong , not a scope issue !
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above also variable scoping it, = number you can use it on the left is not an expression . Joe Smith is equal to John Doe . Can you say what Joe Smith John Doe at dinner equal
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learn
String str = in.readLine () is a statement that defines the variable
used to make a judgment is not enough
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ah , this is the meaning
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+1   
java can not define multiple variables with the same name  

+1
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while ((String str = in.readLine ())! = null) in   
executed first in.readLine () to get the results   
then assign the result to str   
The scope is str (String str = in.readLine ()) brackets, this bracketed value str   
out of the brackets str be recycled . .   
 

+1. preferably define variables on the outside . ,
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discussed above, so many people , I say individual bar !
landlord did not try / catch, maybe because of this