diff --git a/lib/testdata_importer.rb b/lib/testdata_importer.rb
new file mode 100644
--- /dev/null
+++ b/lib/testdata_importer.rb
@@ -0,0 +1,76 @@
+require 'tmpdir'
+
+class TestdataImporter
+
+  attr :log_msg
+
+  def import_from_file(problem_name, 
+                       tempfile, 
+                       time_limit, 
+                       memory_limit)
+
+    dirname = TestdataImporter.extract(problem_name, tempfile)
+    return false if not dirname
+    @log_msg = GraderScript.call_import_problem(problem_name,
+                                                dirname,
+                                                time_limit,
+                                                memory_limit)
+    return true
+  end
+
+  protected
+
+  def self.long_ext(filename)
+    i = filename.index('.')
+    len = filename.length
+    return filename.slice(i..len)
+  end
+
+  def self.extract(problem_name, tempfile)
+    testdata_filename = TestdataImporter.save_testdata_file(problem_name,
+                                                            tempfile)
+    ext = TestdataImporter.long_ext(tempfile.original_filename)
+
+    extract_dir = File.join(GraderScript.raw_dir, problem_name)
+    begin
+      Dir.mkdir extract_dir
+    rescue Errno::EEXIST
+    end
+
+    if ext=='.tar.gz' or ext=='.tgz'
+      cmd = "tar -zxvf #{testdata_filename} -C #{extract_dir}"
+    elsif ext=='.tar'
+      cmd = "tar -xvf #{testdata_filename} -C #{extract_dir}"
+    elsif ext=='.zip'
+      cmd = "unzip #{testdata_filename} -d #{extract_dir}"
+    else
+      return nil
+    end
+
+    system(cmd)
+
+    files = Dir["#{extract_dir}/**/1*.in"]
+    return nil if files.length==0
+
+    return File.dirname(files[0])
+  end
+
+  def self.save_testdata_file(problem_name, tempfile)
+    ext = TestdataImporter.long_ext(tempfile.original_filename)
+    testdata_filename = File.join(Dir.tmpdir,"#{problem_name}#{ext}")
+
+    return nil if tempfile==""
+    
+    if tempfile.instance_of?(Tempfile)
+      tempfile.close
+      FileUtils.move(tempfile.path,testdata_filename)
+    else
+      File.open(testdata_filename, "wb") do |f| 
+        f.write(tempfile.read) 
+      end
+    end
+
+    return testdata_filename
+  end
+
+end