Launch U-Compare

Launch U-Compare System

There are three ways to launch U-Compare, Java Web Start (recommended), UCLoader Launcher (alternative), and UCLoader (command line). All these launchers download, update (if any), startup U-Compare automatically.

Using Java Web Start is slightly easier, but sometimes very slow up to your network bandwidth between the U-Compare web server.

Name Required Java Launch From Custom Setting On-demand Download
Java Web Start (recommended) Sun Java 6 update 12 or later
(Java 6 for Mac OS X 10.5 Update 4 or later. See this to fix a bug in Mac Java)
Web browser,
Java Web Start panel,
desktop icon, etc.
Limited Yes
UCLoader Launcher (alternative) Java 6 Executable Jar No No
UCLoader (command line) Java 6 Command Line Any Java Options No

Java Web Start (JWS)

You need Java 6 (see below for how-to-install Java) as Java Web Start is part of Java runtime environment.

We provides several memory setting variations:

These files are Java Web Start launcher file with .jnlp extension. If .jnlp extension is not associated with Java Web Start, you need to select a relevant option like "Open with Java Web Start (TM)". You can also run it from your console:

$ javaws 


  • Install, launch, update are automatic. Each library file is downloaded on demand.
  • Once launched, you can re-launch U-Compare again off-line.
  • Before Java 6 update 10 (1.6.0_10), JWS update mechanism doesn't work properly.
  • Before Java 6 update 12, 64 bit system was not supported by JWS.
  • Java for Mac OS 10.5 Update X corresponds to 1.6.0_07.

If you have found a bug, please set the Java Console shown (run "javaws -viewer" ("Java Preferences" application in MacOSX) to show the setting panel where show-console option exists), and run

then copy the whole console dump and send us via e-mail or in our forum. Thank you for your cooperation.

Java Installation

Oracle Java 6 (formerlly Sun Java 6) is required to run U-Compare.

Windows Users

Most of Windows machines are Java preinstalled. Visit to install/update to latest Java. Windows 2000/XP/Vista/7 are supported.

Mac OSX Users

Mac OSX 10.5 or later has Java preinstalled. We recommend to install the latest version from Apple website: 6

Linux Users (Ubuntu Linux please see below)

You can check your Java version as below:

$ java -version  
java version "1.6.0_15"
Java(TM) SE Runtime Environment (build 1.6.0_15-b03)
Java HotSpot(TM) Client VM (build 14.1-b02, mixed mode, sharing)

If your Java version is 1.6.0_xx then you are ready (excluding some cases, see below), but we recommend to install the latest version. In 64bit Linux, Java Web Start is not included when the Java version is earlier than 1.6.0_13.

If java -version returns "gcj" like

$ java -version
java version "1.4.2"
gcj (GCC) 3.4.6 20060404 (Red Hat 3.4.6-11)
Copyright (C) 2006 Free Software Foundation, Inc.

or returns "OpenJava" "OpenJDK" (this is default in Ubuntu) like

% java -version  
java version "1.6.0"
OpenJDK Runtime Environment (build 1.6.0-b09)
OpenJDK Client VM (build 1.6.0-b09, mixed mode, sharing)
then you have to install Oracle (Sun) Java like:
$ sudo apt-get install sun-java6-jdk sun-java6-jre  
$ sudo apt-get remove openjdk-6-jdk openjdk-6-jre openjdk-6-jre-headless
$ sudo apt-get remove default-jdk default-jre

installation way may differ up to your packager system.

Memory Requirement

U-Compare will work faster as more memory as you allocate, and some components cause OutOfMemoryError when the allocated memory is not enough.

On the other hand, if it is physically impossible to allocate the specified size of memory in your machine, U-Compare (precisely speaking Java itself) will not start up.

UCLoader Launcher

UCLoader Launcher is a launcher file of an executable Jar. Left click this link: ucloader.jar, then

  • select "open with Java SE 6 (notation might be different)", or
  • save this file and right click, "open with Java SE 6 (notation might be different)". If .jar file is associated to Java, double clicking the file would also work.

UCLoader Launcher internally invokes UCLoader (see below), the same application will be started. You can pass VM arguments to UCLoader by "-vmargs" option followed with any VM arguments:

kano@somewhere> java -jar ucloader.jar -vmargs -Xms100m -Xmx200m ...


UCLoader works almost as same as JWS. Please check your Java version first (1.6.0_xx then fine):

kano@somewhere> java -version
java version "1.6.0_07"
Java(TM) SE Runtime Environment (build 1.6.0_07-b06)
Java HotSpot(TM) 64-Bit Server VM (build 10.0-b23, mixed mode)
Then download UCLoader.class, and in the saved directory:
kano@somewhere> java -Xms700m -Xmx1000m UCLoader


  • Install, launch, update are automatic. All of the library files are downloaded at startup.
  • Once launched, you can re-launch U-Compare again off-line.
  • There are many options provided:
kano@somewhere> java -cp . UCLoader --help
Usage: java UCLoader [--jnlp <JNLP_URL>] [--dir <directory>]
[--nocache] [--offline] arguments...
java UCLoader --list [--dir <directory>]
java UCLoader --help
java -Xms700m -Xmx1000m UCLoader

--offline does not attempt to check the web server for update.

--nocache removes all of the downloaded cache files and fetchs latest ones again from the web server.

--dir option can change the cache folder, which default location is [user.home]/.U-Compare/jars/.

--jnlp specifies URL of the JNLP launcher file.

Download Importable Archive Files

You can import .ucz packages below, by 1. download the package, 2. (from U-Compare menu) Workflow > Import Workflow/Components, 3. specify the downloaded package.

lingpipe.ucz package includes the U-Compare compatible version of LingPipe tools originally developed by Alias-i, wrapped by CCP, LingPipe Sentence Detector, POS tagger, Named Entity Recognizers. Please refer to our component list for details. This distribution is based on the Alias-i special research free license, see their license page for details.