java.net.SocketTimeoutException: connect timed out when connecting to postgresql using jdbc - postgresql

Question

We are planning to switch DB from Oracle to PostgreSQL. After creating tables, I am about to load actual data into PostgreSQL tables. In order to do it, I connect to db using JDBC. It gives me error like below.
Connection Failed! Check output console
org.postgresql.util.PSQLException: The connection attempt failed.
at org.postgresql.core.v3.ConnectionFactoryImpl.openConnectionImpl(ConnectionFactoryImpl.java:275)
at org.postgresql.core.ConnectionFactory.openConnection(ConnectionFactory.java:49)
at org.postgresql.jdbc.PgConnection.<init>(PgConnection.java:194)
at org.postgresql.Driver.makeConnection(Driver.java:450)
at org.postgresql.Driver.connect(Driver.java:252)
at java.sql.DriverManager.getConnection(DriverManager.java:664)
at java.sql.DriverManager.getConnection(DriverManager.java:247)
at JDBCExample.main(JDBCExample.java:31)
Caused by: java.net.SocketTimeoutException: connect timed out
at java.net.PlainSocketImpl.socketConnect(Native Method)
at java.net.AbstractPlainSocketImpl.doConnect(AbstractPlainSocketImpl.java:350)
at java.net.AbstractPlainSocketImpl.connectToAddress(AbstractPlainSocketImpl.java:206)
at java.net.AbstractPlainSocketImpl.connect(AbstractPlainSocketImpl.java:188)
at java.net.SocksSocketImpl.connect(SocksSocketImpl.java:392)
at java.net.Socket.connect(Socket.java:589)
at org.postgresql.core.PGStream.<init>(PGStream.java:68)
at org.postgresql.core.v3.ConnectionFactoryImpl.openConnectionImpl(ConnectionFactoryImpl.java:144)
... 7 more
At first I thought that data loading may take time and could cause this kind of problem, but I tested with following JDBC connection java. It still returns same error like above.
public class JDBCExample {
public static void main(String[] argv) {
System.out.println("-------- PostgreSQL "
+ "JDBC Connection Testing ------------");
try {
Class.forName("org.postgresql.Driver");
} catch (ClassNotFoundException e) {
System.out.println("Where is your PostgreSQL JDBC Driver? "
+ "Include in your library path!");
e.printStackTrace();
return;
}
System.out.println("PostgreSQL JDBC Driver Registered!");
Connection connection = null;
try {
connection = DriverManager.getConnection(
"jdbc:postgresql://aaa.bbb.ccc.ddd:5432/test", "tom",
"secret");
} catch (SQLException e) {
System.out.println("Connection Failed! Check output console");
e.printStackTrace();
return;
}
catch (Exception e) {
e.printStackTrace();
}
if (connection != null) {
System.out.println("You made it, take control your database now!");
} else {
System.out.println("Failed to make connection!");
}
}
}
In this case, what should I check first? There is some log file recording these errors in Postgresql? Is this something related with firewall? I even do not know our coporate has firewall? Could you give some guidance for this issue?