The code for getfreeconnection is as follows:
Public connection getfreeconnection (){
// Return the conn class of the database connection to intercept the close method.
Connection conn2 = NULL;
If (conn instanceof connection ){
Conn2 = (connection) proxy. newproxyinstance (conn. getclass (). getclassloader (), conn. getclass (). getinterfaces (), this );
}
Return conn2;
}
There is no problem with the database driver of mysqlv5. When using the database drivers of mysqlv6 and Oracle, the following error is reported: Java. Lang. classcastexception: $ proxy0 cannot be cast to Java. SQL. Connection
At dbpoolimpl. _ connection. getfreeconnection (_ connection. Java: 126)
At dbpoolimpl. connectionfactory. getfreeconnection (connectionfactory. Java: 113)
At dbpoolimpl. database_task.checkdatabase (database_task.java: 83)
At dbpoolimpl. database_task.processhandle (database_task.java: 227)
After searching online for a long time, I finally found a solution and changed the statement for creating the proxy class to "conn2 = (connection) proxy. newproxyinstance (Conn. getclass (). getclassloader (), new class [] {connection. class}, this );
The reason is that conn. getclass (). the getinterfaces () method generates an array of class classes. The first element of this array must be a connection to convert the created proxy class to a connection object, you can use the following statement class [] interfaces = Conn. getclass (). getinterfaces (); For (Class C: interfaces) {system. out. println (C. getcanonicalname ();} print the conn when different database drivers are used. getclass (). what are the elements in getinterfaces ()?
