Why does Service.providers(java.sql.Driver.class) can always get mysql's driver? p -


i'm testing proxool connection pool (the db mysql), , find curious case, mysql's driver can registered drivermanager though don't explicitly invoke 

class.forname("com.mysql.jdbc.driver")

while proxool's driver cann't. , jdk code , find clue, that

service.providers(java.sql.driver.class)

can mysql's driver while cann't proxools. maybe reason. , question why method can automatically find mysql's driver?

the following testing code:

public static void main(string[] args) throws exception{    iterator drivers = service.providers(java.sql.driver.class);    while(it.hasnext()){       system.out.println(it.next());    } }

and result is:

sun.jdbc.odbc.jdbcodbcdriver@31d520c4 com.mysql.jdbc.driver@1f5a3d6b


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