我无法连接到我的Oracle database server
. 这是代码:
import java.util.*;
import java.sql.*;
import java.io.IOException;
public class Knigi {
public static void main(String[] args) {
String baza_DRIVER="oracle.jdbc.driver.OracleDriver";
String baza_STRING="jdbc:oracle:thin:@localhost:1521:";
String baza_USERNAME="knigi";
String baza_PASSWORD="knigi";
Locale.setDefault(Locale.ENGLISH); // Vazhno e bidejkji Oracle treba da znae kakvi poraki da pojavuva
try {
Driver Driver = (Driver)Class.forName(baza_DRIVER).newInstance();
Connection Conn = DriverManager.getConnection(baza_STRING,baza_USERNAME,baza_PASSWORD);
PreparedStatement Statement = Conn.prepareStatement("SELECT * FROM zhanrovi");
ResultSet zhanrovi = Statement.executeQuery();
boolean isEmpty = !zhanrovi.next();
boolean hasData = !isEmpty;
while (hasData) {
System.out.println("Zhanr: "+zhanrovi.getString("ZH_IME"));
PreparedStatement Statement2 =
Conn.prepareStatement("select * from knigi where ZH_BR = ?");
Statement2.setInt(1,zhanrovi.getInt("ZH_BR"));
ResultSet knigi = Statement2.executeQuery();
boolean isEmpty2 = !knigi.next();
boolean hasData2 = !isEmpty2;
if (isEmpty2) {
System.out.println(" - nema knigi");
} else {
System.out.println(" - Knigi:");
};
while (hasData2) {
System.out.println(
" " +
knigi.getString("ISBN") +
" - " +
knigi.getString("NASLOV")+" ");
hasData2=knigi.next();
}
knigi.close();
hasData=zhanrovi.next();
}
zhanrovi.close();
Conn.close();
} catch (Exception e) {
System.out.println(e);
}
}
}
我收到了这条消息:
java.sql.SQLException: Io exception: Connection refused(DESCRIPTION=(TMP=)(VSNNUM=186646784)(ERR=12504)(ERROR_STACK=(ERROR=(CODE=12504)(EMFI=4))(ERROR=(CODE=12504)(EMFI=4))))
在学校,这个例子很有效。问题出在哪里??