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This noncompliant code example casts the value returned by the read() method directly to a value of type byte and then compares this value with -1 in an attempt to detect the end of the stream.

FileInputStream in;
// initialize stream 
byte data;
while ((data = (byte) in.read()) != -1) { 
  // ... 
}

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Use a variable of type int to capture the return value of the byte input method. When the value returned by read() is not -1, it can be safely cast to type byte. When read() returns 0x000000FF, the comparison will test against 0xFFFFFFFF, which evaluates to false.

FileInputStream in;
// initialize stream 
int inbuff;
byte data;
while ((inbuff = in.read()) != -1) { 
  data = (byte) inbuff;
  // ...  
}

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This noncompliant code example casts the value of type int returned by the read() method directly to a value of type char, which is then compared with -1 in an attempt to detect the end of stream. This conversion leaves the value of data as 0xFFFF (e.g., Character.MAX_VALUE) instead of -1. Consequently, the test for the end of file never evaluates to true.

FileReader in;
// initialize stream 
char data;
while ((data = (char) in.read()) != -1) { 
  // ... 
}

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Use a variable of type int to capture the return value of the character input method. When the value returned by read() is not -1, it can be safely cast to type char.

FileReader in;
// initialize stream 
int inbuff;
char data;
while ((inbuff = in.read()) != -1) { 
  data = (char) inbuff;
  // ...  
}

...

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