Name: saC57035 Date: 12/01/96


The java.io.PushbackInputStream.unread(ch) method works wrong
with ch out of range 0..255.
It assigns ch to instance variable `pushBack' skipping "& 0xFF" operation.

Here is the example demonstrating the bug:

-----------------Test.java------------------------
import java.io.*;

public class Test {

public static void main( String argv[] ) {
 byte[] data = {30};
 int b1,b2;
 PushbackInputStream in = new PushbackInputStream(new ByteArrayInputStream(data));
 try {
   in.unread(-1);
   b = in.read();
   System.out.println("The following bytes should be equal: "+(-1 & 0xFF)+" and "+b);
 } catch (Throwable e) {
   System.out.println("Unexpected "+e+" is thrown");
 }
}
---------Output from the test---------------------
The following bytes should be equal: 255 and 30
--------------------------------------------------

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