POI对word的读取

public class WordUtil {

	public static String readDoc(String file) throws Exception{
		FileInputStream fis = new FileInputStream(file);
		WordExtractor word = new WordExtractor();
		String text = word.extractText(fis);
		return text;
	}
	
	
	public static void main(String[] args) {
		String file = "d:\\lucene.doc";
		String txt = "";
		try {
			txt = readDoc(file);
		} catch (Exception e) {
			e.printStackTrace();
		}
		System.out.println(txt);
	}
	
}

java.lang.StringIndexOutOfBoundsException: String index out of range: -1738
	at java.lang.AbstractStringBuilder.substring(AbstractStringBuilder.java:882)
	at java.lang.StringBuffer.substring(StringBuffer.java:417)
	at org.apache.poi.hwpf.model.TextPiece.substring(TextPiece.java:88)
	at org.textmining.text.extraction.WordExtractor.extractText(WordExtractor.java:179)
	at cn.safetybase.doc.WordUtil.readDoc(WordUtil.java:28)
	at cn.safetybase.doc.WordUtil.main(WordUtil.java:37)