/**
* Build and return a temporary file in the same directory and with the same extension as the
* specified file.
*/
protected File buildTempFile(File file) throws IOException {
int i = file.getName().lastIndexOf('.');
String ext = ((i == -1) ? ".zip" : file.getName().substring(i));
File tempFile = File.createTempFile("temp", ext, file.getParentFile());
return tempFile;
}
