Update comments and consolidate methods

src/main/java/com/conveyal/analysis/util/HttpUtils.java

@@ -30,14 +30,6 @@ public static Map<String, List<FileItem>> getRequestFiles (HttpServletRequest re
  // The Javadoc on this factory class doesn't say anything about thread safety. Looking at the source code it
  // all looks threadsafe. But also very lightweight to instantiate, so in this code run by multiple threads
  // we play it safe and always create a new factory.
- // Setting a size threshold of 0 causes all files to be written to disk, which allows processing them in a
- // uniform way in other threads, after the request handler has returned. This does however cause some very
- // small form fields to be written to disk files. Ideally we'd identify the smallest actual file we'll ever
- // handle and set the threshold a little higher. The downside is that if a tiny file is actually uploaded even
- // by accident, our code will not be able to get a file handle for it and fail. Some legitimate files like
- // Shapefile .prj sidecars can be really small.
- // If we always saved the FileItems via write() or read them with getInputStream() they would not all need to
- // be on disk.
  try {
  ServletFileUpload sfu = new ServletFileUpload();
  return sfu.parseParameterMap(req);
@@ -69,15 +61,12 @@ public static String getFormField(Map<String, List<FileItem>> formFields, String
  }
  }
 
- public static List<File> storeFileItemsAndUnzip(List<FileItem> fileItems) {
- return storeFileItemsAndUnzip(fileItems, FileUtils.createScratchDirectory());
- }
-
  /**
- * Convert `FileItem`s into `File`s and move them into the given directory. Automatically unzip files. Return the
- * list of new `File` handles.
+ * Convert `FileItem`s into `File`s and move them into a temp directory. Automatically unzip files. Return the list
+ * of new `File` handles.
  */
- public static List<File> storeFileItemsAndUnzip(List<FileItem> fileItems, File directory) {
+ public static List<File> storeFileItemsAndUnzip(List<FileItem> fileItems) {
+ File directory = FileUtils.createScratchDirectory();
  List<File> files = new ArrayList<>();
  for (FileItem fi : fileItems) {
  File file = storeFileItemInDirectory(fi, directory);
@@ -91,6 +80,9 @@ public static List<File> storeFileItemsAndUnzip(List<FileItem> fileItems, File d
  return files;
  }
 
+ /**
+ * Convert `FileItem`s into `File`s and move them into a temporary directory. Return the list of new `File` handles.
+ */
  public static List<File> storeFileItems(List<FileItem> fileItems) {
  File directory = FileUtils.createScratchDirectory();
  List<File> files = new ArrayList<>();