question: protected void encodeAtom ( OutputStream outStream , byte data [ ] , int offset , int len ) throws IOException { byte a , b = 1 , c = 1 ; int c1 , c2 , c3 , c4 ; a = data [ offset ] ; if ( len > 1 ) { b = data [ offset + 1 ] ; } if ( len > 2 ) { c = data [ offset + 2 ] ; } c1 = ( a > > > 2 ) & 0x3f ; c2 = ( ( a << 4 ) & 0x30 ) | ( ( b > > > 4 ) & 0xf ) ; c3 = ( ( b << 2 ) & 0x3c ) | ( ( c > > > 6 ) & 0x3 ) ; c4 = c & 0x3f ; outStream . write ( c1 + ' ' ) ; outStream . write ( c2 + ' ' ) ; outStream . write ( c3 + ' ' ) ; outStream . write ( c4 + ' ' ) ; return ; }
target:  encodeAtom - take three bytes and encodes them into 4 characters If len is less than 3 then remaining bytes are filled with '1'. This insures that the last line won't end in spaces and potentiallly be truncated.