prepareAndCheck();
    public void execute() throws BuildException {        if (_setid == null) {            throw new BuildException("setid is required in ivy cachefileset");        }        try {            FileSet fileset = new FileSet();            fileset.setProject(getProject());            getProject().addReference(_setid, fileset);            fileset.setDir(getCache());                        List paths = getPaths();            if (paths.isEmpty()) {                NameEntry ne = fileset.createExclude();                ne.setName("**/*");            } else {                for (Iterator iter = paths.iterator(); iter.hasNext();) {                    String p = (String)iter.next();                    NameEntry ne = fileset.createInclude();                    ne.setName(p);                }            }        } catch (Exception ex) {            throw new BuildException("impossible to build ivy cache fileset: "+ex.getMessage(), ex);        }            }