java - JDBC API specification and implementation -

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i going through jdbc api's (mainly java.sql package) after writing simple jdbc programs.

for example, in java.sql, below declaration:

public interface connection extends wrapper, autocloseable

so, per understanding, these specifications have implemented database vendors, in form of jdbc drivers.

in sample program used h2 db, downloaded jdbc driver.

now, jar should have implementation of java.sql.connection, , saw in .jar (jdbc driver) (under package --> org.h2.jdbc):

public class org.h2.jdbc.jdbcconnection extends org.h2.message.traceobject implements java.sql.connection {

the jdbc driver jar implement java.sql.connection, expected; java.sql.connection from? (it implements java.sql.connection), definition of java.sql.connection coming from?

any pointers clear doubt helpful.

it's in jdk, since able @ its documentation in jdk javadoc.


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