java BufferedReader和InputStreamReader的区别

BufferedReader:  
  Read   text   from   a   character-input   stream,   buffering   characters   so   as   to   provide   for   the   efficient   reading   of   characters,   arrays,   and   lines.    
  
  InputStreamReader:  
  An   InputStreamReader   is   a   bridge   from   byte   streams   to   character   streams:   It   reads   bytes   and   decodes   them   into   characters   using   a   specified   charset.