Accessing databases within a jar file with classpath
Derby Developer's Guide
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Databases in a jar or zip file are always opened read-only and there is currently no
support to allow updates of any type.
Accessing databases within a jar file using the classpath
Once an archive containing one or more Derby databases has been created it can be
placed in the classpath. This allows access to a database from within an application
without the application's knowing the path of the archive.
When jar or zip files are part of the classpath, you do not have to specify the jar
subsubprotocol to connect to them.
To access a database in a zip or jar file in the classpath:
1. Set the classpath to include the jar or zip file before starting up Derby:
CLASSPATH="C:\dbs.jar;%CLASSPATH%"
2. Connect to a database within the jar or zip file with one of the following connection
URLs:
Standard syntax:
jdbc:derby:/databasePathWithinArchive
Syntax with subsubprotocol:
jdbc:derby:classpath:/databasePathWithinArchive
For example:
jdbc:derby:/products/boiledfood
jdbc:derby:classpath:/products/boiledfood
Connecting to databases with ambiguous paths to databases in the file system
Use the basic connection URL syntax only if the database path specified does not also
point to a Derby database in the file system.
If this is the case, the connection attempt might fail or connect to the wrong database.
Use the form of the syntax with the subsubprotocol to distinguish between the databases.
For example:
jdbc:derby:classpath:/products/boiledfood
Connecting to databases when the path is ambiguous because of databases in the
classpath
To connect to a database in the file system when the connection URL that you would
use would be ambiguous with a database in the classpath, use the following form of the
connection URL.
jdbc:derby:directory:databasePathInFileSystem
For example,
jdbc:derby:directory:/products/boiledfood
Apart from the connection URL, databases in archives in the classpath behave just like
databases in archives accessed through the file system. However, databases in archives
are read-only.
Databases on read-only media and DatabaseMetaData
Databases on read-only media return true for DatabaseMetaData.isReadOnly.
