I would use Apache Ant, which has an API to call tasks from Java code rather than from an XML build file.
Project p = new Project();
p.init();
Zip zip = new Zip();
zip.setProject(p);
zip.setDestFile(zipFile); // a java.io.File for the zip you want to create
zip.setBasedir(new File("D:\\reports"));
zip.setIncludes("january/**");
zip.perform();
Here I'm telling it to start from the base directory D:\reports
and zip up the january
folder and everything inside it. The paths in the resulting zip file will be the same as the original paths relative to D:\reports
, so they will include the january
prefix.