Altering the Crawler Java classpath
The Ultra Search Crawler is a pure Java application
and runs in a Java virtual machine. A Java virtual
machine uses the Java classpath to find classes during
runtime. When Ultra Search is installed, the default
Crawler classpath is stored in the database. Whenever
a new Ultra Search instance is created, this default
classpath is copied and used as the Crawler classpath for
that specific instance.
Reasons for altering the Crawler Java classpath
Ordinarily, you will not need to alter the Crawler
Java classpath. However, there may be specific reasons
for you to do so. One such reason may be to
replace the JavaMail™ reference implementation with
a third party JavaMail™ implementation.
Understanding the difference between the Crawler
classpath and the Remote Crawler classpath
The Crawler classpath refers to the classpath of a
crawler that runs on the same host
where Ultra Search Server Component is installed.
However, Ultra Search allows Remote Crawlers to be run on other
hosts for scalability (see Using the Remote Crawler).
Remote Crawler activation uses Java Remote Method
Invocation technology. As a result, the classpath
setting of a Remote Crawler is inherited from the
classpath settings of the RMI Registry and RMI Daemon.
Altering the Crawler Java classpath on the Ultra
Search Server host
- Login in to the host where the Ultra Search
Server Component is installed. Locate
the file $ORACLE_HOME/ultrasearch/admin/wk0cpath.sql.
- Using SQL*Plus, run the wk0cpath.sql script as
the WKSYS super-user or as a database user that has
been granted the WKADMIN role.
- When prompted, specify whether you want to alter
the default classpath or an instance specific
classpath. Altering the default classpath will cause
all subsequent created instances to use that
classpath. Existing instances will not be modified.
- When prompted, enter the Ultra Search instance
name if you are attempting to modify an instance
specific classpath. If you are modifying the default
classpath, you do not need enter anything here.
- When prompted, specify whether you want to update
the entire classpath or append to it. Appending to a
classpath adds entries to the beginning of
it. Normally, entries earlier on in the classpath
override later entries in the case of duplicate classes.
- When prompted, enter the new classpath if updating
the entire classpath. Alternatively, if you are
appending one or more directories or library files to
the classpath, enter these separated by the classpath
separator for the platform on which the Ultra Search
Server Component is installed (the colon on unix platforms or the semicolon on windows platforms)
Altering the Crawler Java classpath on a Remote Crawler host
- Login in to the host where the Ultra Search
Middle-Tier Components are installed on a remote
crawler host. If the host is a unix machine, locate
the file
$WEB_ORACLE_HOME/ultrasearch/tools/remotecrawler/scripts/unix/define_env.
If the host is a windows NT machine, locate
the file $WEB_ORACLE_HOME/ultrasearch/tools/remotecrawler/scripts/winnt/define_env.bat.
- The define_env file specifies all environment
settings used by the RMI subsystem. To alter the
classpath, simply use a text editor to modify the
APPLICATION_CLASSPATH variable.
- You must restart the RMI subsystem before these
changes can take effect. Click here for more details on starting
up the RMI subsystem.
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