title: How to extract the text of a .ppt file with tika?
body: <p>I have extracted the text of a .pdf file with tika using <code>AutoDetectParser</code> class. but when I use the same code for extracting the text of a .ppt file, it throws an exception.  How to do it? 
  thanks</p>
  
  <p>EDIT:<br>
  The code that I used is:  </p>
  
  <pre><code>File file = new File("1.ppt");
  InputStream input = new FileInputStream(file);
  Parser autoDetectParser = new AutoDetectParser();
  Metadata metadata = new Metadata();
  StringWriter writer = new StringWriter();
  ContentHandler handler = new WriteOutContentHandler(writer);
  autoDetectParser.parse(input, handler, metadata, new ParseContext());
  </code></pre>
  
  <p>and the exception was:</p>
  
  <pre><code>java.lang.NoSuchFieldError: SMALLER_BIG_BLOCK_SIZE_DETAILS
  at org.apache.poi.poifs.filesystem.NPOIFSFileSystem.&lt;init&gt;(NPOIFSFileSystem.java:93)
  at org.apache.poi.poifs.filesystem.NPOIFSFileSystem.&lt;init&gt;(NPOIFSFileSystem.java:190)
  at org.apache.poi.poifs.filesystem.NPOIFSFileSystem.&lt;init&gt;(NPOIFSFileSystem.java:184)
  at org.apache.tika.parser.microsoft.POIFSContainerDetector.getTopLevelNames(POIFSContainerDetector.java:371)
  at org.apache.tika.parser.microsoft.POIFSContainerDetector.detect(POIFSContainerDetector.java:165)
  at org.apache.tika.detect.CompositeDetector.detect(CompositeDetector.java:61)
  at org.apache.tika.parser.AutoDetectParser.parse(AutoDetectParser.java:113)
  at ppt.PPTParserTest.test3(PPTParserTest.java:52)
  </code></pre>
  
  <p>I found out that the problem caused by some extra <code>jars</code> that have been in my <code>classpath</code>.</p>