HOWTO: Automate Excel from Java

• Microsoft Win32 Virtual Machine for Java
• Visual J++ 1.0, 1.1,
• SDK for Java 2.0
• Microsoft Win32 Virtual Machine for Java
• Internet Explorer 3.x,4.0.

SUMMARY

This article illustrates how to call a COM object like Excel from Java. It provides code samples that show how you can make an Excel application visible and open an existing Excel file. There are two code samples. One illustrates how to invoke Excel 7.0 from Java and the other shows how to invoke Excel 8.0 from Java. You will find the classes and interfaces to be quite different in Excel 8.0.

MORE INFORMATION

Before using code samples 1 and 2, follow these steps below:

1. Use the Java Applet Wizard to create a default Applet or Application.

2. Run JAVATLB or JACTIVEX(utility similar to JAVATLB and supported by the SDK for Java 2.0)on the Microsoft Excel7.0 Object Library if you are using Excel 7.0 or the Microsoft Excel 8.0 Object Library if you are using Excel 8.0. This will create Java descriptions of the Excel Object.

   NOTE: If you are using JACTIVEX, then you will need to build this sample with the JVC.EXE that ships with the SDK2.0 for Java. You can download the SDK for Java 2.0 from http://www.microsoft.com/java/.

3. Use the import statement to import the classes of the Excel Object Library into your Java project.

4. Insert either one of the two code snippets in your Java Project to automate Excel from Java.

Code Sample 1

   import xl5en32.*;
   import com.ms.com.*;
   public void TestExcel()
   {
      _Global gbl = (_Global) new _ExcelApplication();
      Variant param = gbl.Application();
      Application app = (Application) param.getDispatch();
      param.putInt(xl5en32.Constants.xlVisible);
      app.putVisible(param);

      Variant vtemp = new Variant();
      vtemp.noParam();

      Variant vtWorkbooks = Dispatch.get(gbl,"Workbooks");
      Workbooks wbs = (Workbooks)vtWorkbooks.getDispatch();

      Variant vtName = new Variant();
      VtName.putStringRef("C:\\book1.xls");

      Variant vtEmpty = new Variant();
      vtEmpty.noParam();
      wbs.Open(vtName,vtEmpty,vtEmpty,vtEmpty,vtEmpty,vtEmpty,vtEmpty,
               vtEmpty,vtEmpty,vtEmpty,vtEmpty,vtEmpty,vtEmpty);
   }

Code Sample 2

   import excel8.*;
   import com.ms.com.*;

   _Global globXL=null;
   _Application appXL=null;
   Workbooks books=null;
   _Workbook book = null;

   try{
      globXL = (_Global)new Global();
      appXL = (_Application)globXL.getApplication();
      appXL.putVisible(0,true);
      books = (Workbooks)appXL.getWorkbooks();

      Variant vTemp = new Variant();
      vTemp.putString("c:\\book1.xls");

      Variant vOptional = new Variant();
      vOptional.noParam();
      book =

      }
      catch(ComFailException e)
      {
         System.out.println(e.getMessage());
      }

REFERENCES

For the latest Knowledge Base articles and other support information on Visual J++ and the SDK for Java, see the following page on the Microsoft Technical Support site:

   http://support.microsoft.com/support/visualj/
   http://support.microsoft.com/support/java/

Keywords          : kbcode kbinterop kbprg JCOM
Technology        : kbInetDev
Platform          : WINDOWS
Issue type        : kbhowto