Issue with Jackcess ExportFilter

Issue with Jackcess ExportFilter

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I found a great library called Jackcess, allows you to convert, parse create, etc with Microsoft Access.

The aim is to convert, which this code does successfully.

There is a Filter functionality upon export, this can be seen on the link to the documentation below. The aim is to use the first 3 columns, exclude the rest of the data.

ExportUtil Documentation

Applying the filter object doesn't work, does anyone know if there's something else that needs to be ahcieved first... * scratching my head here *

Export Filter Documentation

public void db_dump(String mdbFile, String outputDir) {
    File file = new File("/Users/testUser/Downloads/example.mdb");
    if(file != null) {
    File outDir = new File("/Users/testUser/Desktop/output123");
    boolean success = outDir.mkdir();
        if (success) {
            Database db = null;
            try {
                db = DatabaseBuilder.open(file);
                Table t = db.getTable("MappedCHTCP");
                List<Column> cols  = new List<Column>() 
                    @Override methods for list ommited .... size(), contains(), etc
                System.out.println(t.getColumns());

//                  cols.add(0,t.getColumn("word"));

                 for (Column c : t.getColumns()) {
                      if((c != null) && (c.getColumnIndex() < 3)) {
                          System.out.println(c.getName());
                          cols.add(c);
                      }
                 }

                SimpleExportFilter ef = new SimpleExportFilter(); //THIS IS THE PROBLEM
                ef.filterColumns(cols);

                File csvFile = new File(outDir+File.separator+"MappedCHTCP.csv");
                ExportUtil.exportFile(db, "MappedCHTCP", csvFile, false, null, '"',ef); //NOT ABLE TO APPLY FILTER

            } catch (IOException e) {
                e.printStackTrace();
            }

        }
    }
}

java ms-access csv jackcess

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edited Apr 15 '14 at 13:41

Gord Thompson

73.6k1180191

asked Apr 15 '14 at 8:58

RST

352621

• Thanks for looking... it's really strange! It doesn't matter weather you construct the object inside the exportFile function. – RST Apr 15 '14 at 17:54

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1 Answer

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up vote3down voteaccepted

Based on what I found in the unit test code here, the following sample code seems to work. It exports only the first three (3) columns of the table named [Members]:

package jackcessTest;

import java.io.File;
import java.util.*;
import com.healthmarketscience.jackcess.*;
import com.healthmarketscience.jackcess.util.ExportFilter;
import com.healthmarketscience.jackcess.util.ExportUtil;
import com.healthmarketscience.jackcess.util.SimpleExportFilter;

public class JackcessTest {

    public static void main(String[] args) {
        try (Database db = DatabaseBuilder.open(
                new File("C:/Users/Public/mdbTest.mdb"))) {

            ExportFilter eFilter = new SimpleExportFilter() {
                private List<Column> _cols = new ArrayList<Column>();
                private int _colIdx = 0;
                @Override
                public List<Column> filterColumns(List<Column> columns) {
                    for (Column c : columns) {
                        if (_colIdx++ < 3) _cols.add(c);
                    }
                    return _cols;
                }
            };

            ExportUtil.exportFile(
                    db, 
                    "Members", 
                    new File("C:/Users/Public/zzzJdump.csv"), 
                    true, 
                    ",", 
                    '"', 
                    eFilter);
        } catch (Exception e) {
            e.printStackTrace(System.out);
        }
    }
}

shareimprove this answer

edited Apr 16 '14 at 20:55

answered Apr 16 '14 at 16:16

Gord Thompson

73.6k1180191

• That's brilliant, thank you ever so much! Not very clear is it :). Hopefully this will help someone in the future.– RST Apr 17 '14 at 8:41