2d barcode vb.net indexBase is the property suffix that describes the root directory containing the in Java

Maker DataMatrix in Java indexBase is the property suffix that describes the root directory containing the

index directories. The default value is the current directory (which is usually where your virtual machine has been launched). indexName is the property suffix that describes the index directory name; the full path is defined by indexBase plus indexName. The default value for indexName is the index name (which itself defaults to the fully qualified class name of the indexed entity); indexName is rarely used in Hibernate Search deployments.

While Hibernate Search lets you define your filesystem index directory in a lot of funky ways, the authors recommend that you define a single root directory (using hibernate.search.default.indexBase) where all index directories are stored and let the default strategy play its role from here. You ll have a better understanding of what s going on, and maintenance will be much easier. Listing 5.3 is an example of a directory structure where indexes follow Hibernate Search s conventions.

The only property to set is indexBase, the root directory # File directory structure /Users Each index directory will be /Production under indexBase and named /indexes from its index /com.manning.hsia.dvdstore.model.Item /com.manning.hsia.dvdstore.model.Actor

If possible, use a local filesystem or a storage area network (SAN) filesystem. Regular network filesystems (NFS) tend to be problematic for Lucene. Lucene needs to acquire a global pessimistic lock when it updates an index. The default locking strategy represents the lock as a file. Due to some caching strategies in place in most network filesystems, the lock file cannot always be read appropriately. If you absolutely must use a network filesystem, the authors recommend that you check the Lucene resources available on the subject. The Lucene team is making a lot of progress in this area. While a filesystem is the mainstream way of storing indexes, another interesting strategy is to store the index in memory.

It s possible to define a Lucene index as stored in memory. Of course, as soon as the application shuts down (more precisely as soon as the Hibernate SessionFactory or EntityManagerFactory is closed), the index data goes away. It is nevertheless quite useful in several situations. The primary situation is unit testing. Unit testing has spread across the development community. The general idea is to test individual functionalities or subsystems independently from each other. Speed is a primary concern. If a test suite is too long, people have the tendency to not launch it and commit the code hoping for the best (ah, humans!). Unit test purists test individual classes independently from each other and are horrified when two subsystems are tested together. Let s discuss what we, the authors, think is a slightly more pragmatic approach. Thanks to in-memory databases such as HSQLDB, H2, or Derby, and thanks to the abstraction provided by Hibernate, it s possible to test a system all the way down to the database from a fresh data set in a matter of seconds or milliseconds (as opposed to minutes when a remote database is used). Hibernate Search lets you embrace this fast

approach to test Lucene indexes. Unit tests using both in-memory databases and inmemory indexes can initiate quickly the data set before each test. The test then verifies the application behavior in a well-defined environment that s cleaned between each test. While it s possible to do the same with a regular database and a filesystem based index, the in-memory version makes the unit test suite run much faster, because it avoids unnecessary network or filesystem input/output. You can find more information on unit testing and in-memory approaches in section 9.5.2. If you followed the recommendation we gave you in the previous section (define a default directory_provider), you can easily switch from an in-memory provider in your unit tests to a filesystem based directory provider in production (or in your dedicated test environment). Listing 5.4 shows two different configurations, depending on the targeted environment (test or production).