在c3p0连接池中设置SQLite连接属性

Question

To specify SQLite connection properties there is org.sqlite.SQLiteConfig and it goes something like this:

    org.sqlite.SQLiteConfig config = new org.sqlite.SQLiteConfig();
    config.setReadOnly(true);
    config.setPageSize(4096); //in bytes
    config.setCacheSize(2000); //number of pages
    config.setSynchronous(SQLiteConfig.SynchronousMode.OFF);
    config.setJournalMode(SQLiteConfig.JournalMode.OFF);
    SQLiteConnectionPoolDataSource dataSource = new SQLiteConnectionPoolDataSource();

Creating a connection pool with c3p0 goes something like this:

        ComboPooledDataSource cpds = new ComboPooledDataSource();
        cpds.setDriverClass("org.sqlite.JDBC");
        cpds.setJdbcUrl("jdbc:sqlite:/foo/bar");
        cpds.setMaxPoolSize(10);

Question: how do I create a DataSource that combines the two, letting me set things like the connection pool's max-pool-size and sqlite's synchronous mode?

Answer 1

Try

//put the imports where they really go, obviously...
import javax.sql.*;
import org.sqlite.*;
import com.mchange.v2.c3p0.*;

// configure SQLite
SQLiteConfig config = new org.sqlite.SQLiteConfig();
config.setReadOnly(true);
config.setPageSize(4096); //in bytes
config.setCacheSize(2000); //number of pages
config.setSynchronous(SQLiteConfig.SynchronousMode.OFF);
config.setJournalMode(SQLiteConfig.JournalMode.OFF);

// get an unpooled SQLite DataSource with the desired configuration
SQLiteDataSource unpooled = new SQLiteDataSource( config );

// get a pooled c3p0 DataSource that wraps the unpooled SQLite DataSource
DataSource pooled = DataSources.pooledDataSource( unpooled );

The DataSource pooled will now be a c3p0 PooledDataSource that wraps an SQLite unpooled DataSource which has been configured as you wish.

Please see c3p0's docs, "Using the DataSources factory class" , and the API docs for the DataSources factory class.

See also the javadocs for SQLite JDBC, which I downloaded from here to answer this question.