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    <div class="moz-cite-prefix">Hi John,<br>
      <br>
      yes, this is a bit waste of space :)<br>
      <br>
      But the empty space is to avoid thinking about header size in the
      consuming class but mainly to avoid breaking the file format when
      we insert new data there.<br>
      <br>
      Regards,<br>
      Peter<br>
      <br>
      On 01.07.2015 02:04, John Zhao wrote:<br>
    </div>
    <blockquote
cite="mid:CA+EBg9S3cEGRXmNBX27dYDtyLuQO5REzZ-d-wf99TQ-Dbgcr0A@mail.gmail.com"
      type="cite">
      <div dir="ltr">Hi,
        <div><br>
        </div>
        <div>
          <div><span
style="color:rgb(128,128,128);font-family:Menlo;font-size:12pt;font-style:italic">/**<br>
            </span><span
style="color:rgb(128,128,128);font-family:Menlo;font-size:12pt;font-style:italic"> * Writes some internal data into the beginning of the specified file.<br>
            </span><span
style="color:rgb(128,128,128);font-family:Menlo;font-size:12pt;font-style:italic"> */<br>
            </span><span
style="color:rgb(0,0,128);font-family:Menlo;font-size:12pt;font-weight:bold">protected void </span><font
              face="Menlo"><span style="font-size:12pt">writeHeader( RandomAccessFile file, </span></font><span
style="color:rgb(0,0,128);font-family:Menlo;font-size:12pt;font-weight:bold">long </span><font
              face="Menlo"><span style="font-size:12pt">length, </span></font><span
style="color:rgb(0,0,128);font-family:Menlo;font-size:12pt;font-weight:bold">int </span><font
              face="Menlo"><span style="font-size:12pt">segmentSize ) </span></font><span
style="color:rgb(0,0,128);font-family:Menlo;font-size:12pt;font-weight:bold">throws </span><font
              face="Menlo"><span style="font-size:12pt">IOException</span></font><br>
            <font face="Menlo"><span style="font-size:12pt">{</span></font></div>
          <div><font face="Menlo"><span style="font-size:12pt">   
                file.seek(</span></font><span
              style="color:rgb(0,0,255);font-family:Menlo;font-size:12pt">0</span><font
              face="Menlo"><span style="font-size:12pt">);</span></font></div>
          <div><font face="Menlo"><span style="font-size:12pt">   
                file.writeUTF(</span></font><span
style="color:rgb(0,128,0);font-family:Menlo;font-size:12pt;font-weight:bold">"GH</span><font
              color="#008000" face="Menlo"><span style="font-size:16px"><b>”</b></span></font><font
              face="Menlo"><span style="font-size:12pt">); // 4 bytes</span></font></div>
          <div><font face="Menlo"><span style="font-size:12pt">   
                file.writeLong(length); // 8 bytes</span></font><br>
            <font face="Menlo"><span style="font-size:12pt">   
                file.writeInt(segmentSize); // 4 bytes</span></font><br>
            <font face="Menlo"><span style="font-size:12pt">   </span></font>
            <span
style="color:rgb(0,0,128);font-family:Menlo;font-size:12pt;font-weight:bold">for </span><font
              face="Menlo"><span style="font-size:12pt">(</span></font><span
style="color:rgb(0,0,128);font-family:Menlo;font-size:12pt;font-weight:bold">int </span><font
              face="Menlo"><span style="font-size:12pt">i = </span></font><span
style="color:rgb(0,0,255);font-family:Menlo;font-size:12pt">0</span><font
              face="Menlo"><span style="font-size:12pt">; i < </span></font><span
style="color:rgb(102,14,122);font-family:Menlo;font-size:12pt;font-weight:bold">header</span><font
              face="Menlo"><span style="font-size:12pt">.</span></font><span
style="color:rgb(102,14,122);font-family:Menlo;font-size:12pt;font-weight:bold">length</span><font
              face="Menlo"><span style="font-size:12pt">; i++)</span></font><br>
            <font face="Menlo"><span style="font-size:12pt">    {</span></font><br>
            <font face="Menlo"><span style="font-size:12pt">       
                file.writeInt(</span></font><span
style="color:rgb(102,14,122);font-family:Menlo;font-size:12pt;font-weight:bold">header</span><font
              face="Menlo"><span style="font-size:12pt">[i]);</span></font><br>
            <font face="Menlo"><span style="font-size:12pt">    }</span></font>
          </div>
          <div><font face="Menlo"><span style="font-size:12pt">}</span></font></div>
          <div><font face="Menlo"><span style="font-size:12pt"><br>
              </span></font></div>
          <div><font face="Menlo"><span style="font-size:12pt">it's
                totally 100 bytes.</span></font></div>
          <div><font face="Menlo"><span style="font-size:12pt">We only
                use 96 bytes of them.</span></font></div>
          <div><font face="Menlo"><span style="font-size:12pt"><br>
              </span></font></div>
          <div><font face="Menlo"><span style="font-size:12pt">It's not
                a problem.</span></font></div>
          <div><font face="Menlo"><span style="font-size:12pt">Just
                curious.</span></font></div>
          <div><font face="Menlo"><span style="font-size:12pt"><br>
              </span></font></div>
          <div><font face="Menlo"><span style="font-size:12pt">It's
                better to use them all, to reduce any further question.
                :)</span></font></div>
          <div><font face="Menlo"><span style="font-size:12pt"><br>
              </span></font></div>
          <div>
            <div class="gmail_signature"><b>Best Regards,</b>
              <div><b>ZhiQiang ZHAO</b></div>
            </div>
          </div>
        </div>
      </div>
      <br>
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      <br>
      <pre wrap="">_______________________________________________
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</pre>
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