¿Cómo instalo Groovy?

Cuando intento ejecutar esto:

sudo apt-get install groovy 

Me sale este gran error:

Setting up oracle-java7-installer (7u3-0~eugenesan~precise4) ...
Downloading...
--2012-04-28 18:43:39--  http://download.oracle.com/otn-pub/java/jdk/7u3-b04/jdk-7u3-linux-i586.tar.gz
Resolving download.oracle.com (download.oracle.com)... 96.17.181.40, 96.17.181.49
Connecting to download.oracle.com (download.oracle.com)|96.17.181.40|:80... connected.
HTTP request sent, awaiting response... 302 Moved Temporarily
Location: https://edelivery.oracle.com/otn-pub/java/jdk/7u3-b04/jdk-7u3-linux-i586.tar.gz [following]
--2012-04-28 18:43:39--  https://edelivery.oracle.com/otn-pub/java/jdk/7u3-b04/jdk-7u3-linux-i586.tar.gz
Resolving edelivery.oracle.com (edelivery.oracle.com)... 184.50.22.174
Connecting to edelivery.oracle.com (edelivery.oracle.com)|184.50.22.174|:443... connected.
HTTP request sent, awaiting response... 302 Moved Temporarily
Location: http://download.oracle.com/errors/download-fail-1505220.html [following]
--2012-04-28 18:43:40--  http://download.oracle.com/errors/download-fail-1505220.html
Connecting to download.oracle.com (download.oracle.com)|96.17.181.40|:80... connected.
HTTP request sent, awaiting response... 200 OK
Length: 5307 (5.2K) [text/html]
Saving to: `./jdk-7u3-linux-i586.tar.gz'

     0K .....                                                 100% 47.2K=0.1s

2012-04-28 18:43:40 (47.2 KB/s) - `./jdk-7u3-linux-i586.tar.gz' saved [5307/5307]

Download done.
sha256sum mismatch jdk-7u3-linux-i586.tar.gz
Oracle JDK 7 is NOT installed.
dpkg: error processing oracle-java7-installer (--configure):
 subprocess installed post-installation script returned error exit status 1
dpkg: dependency problems prevent configuration of groovy:
 groovy depends on default-jre-headless | sun-java6-jre; however:
  Package default-jre-headless is not installed.
  Package oracle-java7-installer which provides default-jre-headless is not configured yet.
  Package sun-java6-jre is not installed.
dpkg: error processing groovy (--configure):
 dependency problems - leaving unconfigured
No apport report written because the error message indicates its a followup error from a previous failure.
                          Errors were encountered while processing:
 oracle-java7-installer
 groovy
E: Sub-process /usr/bin/dpkg returned an error code (1)

Ya tengo Java instalado en mi PC. Cuando corro:

java -version

Yo obtengo :

java version "1.7.0_04"
Java(TM) SE Runtime Environment (build 1.7.0_04-b20)
Java HotSpot(TM) Server VM (build 23.0-b21, mixed mode)

donde estoy cometiendo un error?

Gracias por adelantado.

Me recuperé de este error haciendo:

sudo apt-get purge openjdk*

Esto le pedirá que elimine los openjdkque se han instalado en su sistema. Proceder con eso. Después de openjdkhaber sido eliminado de su PC, puede hacer:

sudo apt-add-repository ppa:groovy-dev/groovy
sudo apt-get update
sudo apt-get install groovy

Esto instala la versión estable. Después de eso haz esto, en tu terminal:

groovy -version

Esto debería darte el resultado:

Groovy Version: 1.8.6 JVM: 1.6.0_24 Vendor: Sun Microsystems Inc. OS: Linux

En cambio, simplemente instalé el GVM (Groovy enVironment Manager) y lo usé para instalar groovy.