Java Database Connectivity
part 7/17 · 28.8 KB total
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There is an extension to the basic JDBC API in the javax.sql.
JDBC connections are often managed via a connection pool rather than obtained directly from the driver.cite-ref-footnotebai202283-3-5-1-jdbc-datasource-14-0[14]
Examples
When a Java application needs a database connection, one of the DriverManager.getConnection() methods is used to create a JDBC Connection. The URL used is dependent upon the particular database and JDBC driver. It will always begin with the "jdbc:" protocol, but the rest is up to the particular vendor.
Connection conn = DriverManager.getConnection(
"jdbc:somejdbcvendor:other data needed by some jdbc vendor",
"myLogin",
"myPassword");
try {
/* you use the connection here */
} finally {
//It's important to close the connection when you are done with it
try {
conn.close();
} catch (Throwable e) { /* Propagate the original exception
instead of this one that you want just logged */
logger.warn("Could not close JDBC Connection", e);
}
}
Starting from Java SE 7 you can use Java's try-with-resources statement to simplify the above code:
try (Connection conn = DriverManager.getConnection(
"jdbc:somejdbcvendor:other data needed by some jdbc vendor",
"myLogin",
"myPassword")) {
/* you use the connection here */
} // the VM will take care of closing the connection
Once a connection is established, a Statement can be created.
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