poi doc转docx

可以使用Apache POI库来将doc文件转换成docx文件。下面是一个简单的Java代码示例：

import java.io.FileInputStream;
import java.io.FileOutputStream;
import org.apache.poi.xwpf.usermodel.XWPFDocument;
import org.apache.poi.hwpf.converter.WordToFoConverter;
import org.apache.poi.hwpf.HWPFDocument;

public class DocToDocxConverter {
   public static void main(String[] args) {
      String docFilePath = "path/to/document.doc";
      String docxFilePath = "path/to/document.docx";
      try {
         FileInputStream inputStream = new FileInputStream(docFilePath);
         HWPFDocument document = new HWPFDocument(inputStream);
         XWPFDocument documentOut = new XWPFDocument();
         WordToFoConverter wordToFoConverter = new WordToFoConverter(documentOut);
         wordToFoConverter.processDocument(document);
         FileOutputStream outputStream = new FileOutputStream(docxFilePath);
         documentOut.write(outputStream);
         outputStream.close();
         System.out.println("File converted successfully");
      } catch (Exception ex) {
         ex.printStackTrace();
      }
   }
}

请确保在代码中替换文档路径。这个示例假定你已经正确地安装了Apache POI库。