title: android copy StringBuffer
body: <p>I have declared two string buffers like,</p>
  
  <pre><code>private StringBuffer buf = new StringBuffer(1024);
  private StringBuffer bufRetro = new StringBuffer(1024);
  </code></pre>
  
  <p>on following code, before bufRetro = buf, buf has proper filled value. However, after copy it, both have no content. How to set one stringBuffer from another one? Thank you.</p>
  
  <pre><code>if(this.v_Id){
  
      buf.append(ch, start, length);
  
      if (bufType.equals(bufOld)){
  
          buf = bufRetro.append(buf);
  
      }
  
      myParsedXMLDataSet.setId(buf.toString());
  
      bufOld = bufType;
  
      bufRetro.delete(0, bufRetro.length());
      bufRetro = buf;
  
      Log.d("id", buf.toString());
  
      buf.delete(0, buf.length());
  </code></pre>