Java validate image header -

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I have a requirement where I do not need to identify the type of image by file extension, but by validating the header . I am trying to validate the JPEG file by magic number verification. 

  file imgFile = new file ("C: \\ user \\ public \\ picture \\ sample image \\ Chrysanthemum.jpg"); Byte [BA] = Files To beatierre (imgfile); // Its a Google Java library int i = 0; If (BA [i] == 0xFF & amp; ba [i + 1] == 0xD8 and b [i + 2] == 0xFF & b [i + 3] == 0xE0) {println ("IsJPEG"); }   
 But the condition is not satisfied at all.  BA [i]  returns  -1 .  
 What am I doing?   
 
 byte  has been signed in Java and has a limit of 128 to 127, which means your  BA [0]   -1  comes out as, while  0xFF  is interpreted as an int as  255  has been done. If you do the bitword and use the  0xFF  with the  and  operator, it converts the signed byte to the correct value and your code will work as follows:  
  file imgFile = new file ("C: \\ user \\ public \\ picture \\ sample picture \\ Chrysanthemum.jpg"); Byte [BA] = Files To Batterier (IMGFile); // Its a Google Java library int i = 0; If ((BA [I] and 0x FF) == 0x FF & amp (BA [I + 1] and 0x FF) == 0xD8 & amp; (BA [I + 2] and 0x FF) == 0x FF & Amp; amp; (b [i + 3] & amp; 0xFF) == 0xE0) {System.out.println ("isJPEG"); }   
 I'm sure what you are using about exact logic, though Wikipedia says that magic numbers for JPEG are as follows:  
 
 JPEG image files start with FF D8 and end with FF D9   
  FF e , you can make Jeffef specific, so You can check why you are checking for it  
  
  file imgFile = new file ("C: \\ user \\" The Public \\ will have the following code to make use of Czech by pictures: \ sample images \\ Chrysanthemum.jpg "); Byte [BA] = Files To Batterier (IMGFile); // Its a Google Java library int i = 0; If ((BA [i] & 0xFF) == 0xFF & amp; (BA [I + 1] and 0xFF) == 0xD8 & amp; (BA [BA.Length = 2] and 0xFF) == 0xFF Amp; (ba [ba.length - 1] and 0xFF) == 0xD 9) {System.out.println ("isJPEG"); }

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