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Can't connect to postgres db with jdbc

Note: I'm calling the security service the problem service here, but I doubt I can connect to the DB with any service- security is just the first one that has to do it.
I'm trying to modify a java application to use postgres instead of oracle, I'm getting connection issues, and my logs are not helpful.
The database is on a remote server, but it is being accessed successfully by other applications. I can connect with the postgres client without issue.
Any ideas where I should look?
The errors:
from the service I'm calling:
2020-08-11 14:47:37 INFO AuthenticationService:32 - Rest Services - starting authentication...
2020-08-11 14:47:38 ERROR AuthenticationService:119 - GetUserInfo: trying to connect to the Rest Serrvice, attempt 1, HTTP Error Code: 500
2020-08-11 14:47:38 ERROR AuthenticationService:120 - Response message: Internal Server Error
2020-08-11 14:47:38 ERROR AuthenticationService:146 - Problem getting User Info: Problem getting User Info 500, message: Internal Server Error
2020-08-11 14:47:38 ERROR AuthenticationService:62 - Problem getting User Info: Problem getting User Info 500, message: Internal Server Error
From the underlying problem service:
2020-08-11 14:47:38 INFO SecurityService:67 - Rest Services - getUserInfo
2020-08-11 14:47:38 INFO SecurityService:87 - Getting User Info from DB...
2020-08-11 14:47:38 ERROR SecurityService:110 - Couldn't establish connection to Database
My context.xml for problem service (resource section is identical in both services):
<?xml version="1.0" encoding="UTF-8"?>
<Context path="/PhoenixSecurity" docBase="PhoenixSecurity"
crossContext="true" reloadable="true" debug="1">
<Resource name="jdbc/CtsRest" auth="Container"
type="javax.sql.DataSource" driverClassName="org.postgresql.Driver"
url="jdbc:postgresql://CORRECT-IP:5432/phoenix"
username="validUser" password="validPassword" maxActive="100" maxIdle="100" maxWait="-1"/>
</Context>

In troubleshooting these sorts of problems check the following in order:
Can you connect to PostgreSQL from another machine on the LAN? If not, it may not be listening on the address?
Can you connect locally? Is it even running?
Now in the case where the second succeeds and the first fails, here are things to check in order:
listen_address in postgresql.conf
firewall rules
Anything in between that might interfere with the network connections.
*Sometimes when you pass localhost in the jdbc url this will be mapped to ipv6 address. Try specifying the the ip4 address explicitly.

Turns out my issue was assuming that the jdbc driver for postgres could create a connection the same way as the one for oracle. It can't. Lesson learned.

CAn't connect to Oracle with Spring Boot and Hibernate

I have a working Spring Boot app (1.2) that uses Postgres. Today I am trying to switch it to Oracle, but when I try to connect I get an exception that says:
java.sql.SQLRecoverableException: IO Error: The Network Adapter could not establish the connection
And below that,
Caused by: java.net.ConnectException: Connection refused
So of course that looks like bad credentials, but I know they are good, and they are working in Oracle SQL Developer just fine. I'm baffled. Here are my properties file entries:
# Properties for Hibernate and Oracle
spring.datasource.driverClassName=oracle.jdbc.driver.OracleDriver
spring.datasource.url=jdbc:oracle:thin:#//earth-db-11:5121/stardev
spring.datasource.username=ops$abcdefg
spring.datasource.password=mypassword
spring.jpa.database-platform=org.hibernate.dialect.Oracle10gDialect
The only idea I have is that there is a $ in the user name, and I have tried escaping it and putting double quotes around it.
Any ideas?
Thanks...
UPDATE:
Many thanks to BonanzaOne, I did have the port number wrong. Correcting that results in a new error:
java.sql.SQLRecoverableException: Listener refused the connection with the following error:
ORA-12514, TNS:listener does not currently know of service requested in connect descriptor
I looked it up of course, but I don't follow what its telling me:
ORA-12514: TNS:listener does not currently know of service requested in connect descriptor
Cause: The listener received a request to establish a connection to a database
or other service. The connect descriptor received by the listener specified a
service name for a service (usually a database service) that either has not yet
dynamically registered with the listener or has not been statically configured
for the listener. This may be a temporary condition such as after the listener
has started, but before the database instance has registered with the listener.
Still, SQL Explorer connects fine.

That exception means that the Oracle listener is not up, or you are trying to connect to a listener that don't exist/not accessible.
My guess is that you trying the wrong port "5121". Oracle default port is 1521.
Can you try with that and see what happens?
From the FAQ there are basically two ways of composing your JDBC string URL:
Old syntax
jdbc:oracle:thin:#[HOST][:PORT]:SID
New syntax
jdbc:oracle:thin:#//[HOST][:PORT]/SERVICE
My guess is that you are using the wrong syntax-SID/Service name combination, in other words, you are using the new syntax that requires the SERVICE name, but you are using the SID name to do it.
Try this: jdbc:oracle:thin:#earth-db-11:1521:stardev
Or maybe find out the Service name and apply it to the new syntax that you are using, instead of the SID name.

Error connecting to Oracle database using JDBC [duplicate]

I am new to Oracle, and am trying to run a simple example code with Java, but am getting this error when executing the code.. I am able to start up the listener via CMD and am also able to run SQL Plus. Can anyone give me a hand and tell me what I might be doing wrong?
Update:
I am using JDBC.
Database is local, and I actually had it working but it stopped working just today. I'm not really sure why though. Would you mind giving me some procedures to follow by since I don't know much.

Either:
The database isn't running
You got the URL wrong
There is a firewall in the way.
(This strange error message is produced by Oracle's JDBC driver when it can't connect to the database server. 'Network adapter' appears to refer to some component of their code, which isn't very useful. Real network adapters (NICs) don't establish connections at all: TCP protocol stacks do that. It would have been a lot more useful if they had just let the original ConnectException be thrown, or at least used its error message and let it appear in the stack trace.)

I had the same problem, and this is how I fixed it.
I was using the wrong port for my connection.
private final String DB_URL = "jdbc:oracle:thin:#localhost:1521:orcll"; // 1521 my wrong port
go to your localhost
(my localhost address) : https://localhost:1158/em
login
user name
password
connect as --> normal
Below 'General' click on LISTENER_localhost
look at you port number
Net Address (ADDRESS=(PROTOCOL=TCP)(HOST=localhost)(PORT=1522))
Connect to port 1522
Edit you connection
change port 1521 to 1522.
done

Another thing you might want to check that the listener.ora file matches the way you are trying to connect to the DB. If you were connecting via a localhost reference and your listener.ora file got changed from:
HOST = localhost
to
HOST = 192.168.XX.XX
then this can cause the error that you had unless you update your hosts file to accommodate for this. Someone might have made this change to allow for remote connections to the DB from other machines.

I figured out that in my case, my database was in different subnet than the subnet from where i was trying to access the db.

I had this error when i renamed the pc in the windows-properties. The pc-name must be updated in the listener.ora-file

Most probably you have listener configured wrongly, the hostname you specify in connection string must be the same as in the listener.
First check the Firewall and network related issues.
Check if Oracle Listener service is available and running. If not you may use Oracle Net Configuration Assistant tool to add and register new listener.
If the above steps are ok then you need to configure Oracle Listener appropriately. You may use Oracle Net Manager tool or edit “%ORACLE_HOME%\network\admin\listener.ora” file manually.
There are 2 options that need to be considered carefully:
Listening Locations associated with the Listener – Hostname(IP) and Port in Listening Location must exactly match the ones used in the connection string.
For example, if you use 192.168.74.139 as target hostname, then there must be Listening Location registered with the same IP address.
Also make sure the you use the same SID as indicated in Database Service associated with the Listener.
https://adhoctuts.com/fix-oracle-io-error-the-network-adapter-could-not-establish-the-connection-error/

IO Error: The Network Adapter could not establish the connection (CONNECTION_ID=iKQM6lBbSLiArrYuDqud8A==)
if you are facing this issue
1- make sure you have downloaded oracle databases like oracle 11g,19c, 21c, or any latest databases.
2- search for services in your computer or type win+r then services.mis then search for oracleservice you will find orcl or xe or any other sid like oracleserviceorcl;
after that you can test your connection using sql developer, sql plus or cmd

To resolve the Network Adapter Error I had to remove the - in the name of the computer name.

In my case, I needed to specify a viahost and viauser. Worth trying if you're in a complex system. :)

For me the basic oracle only was not installed. Please ensure you have oracle installed and then try checking host and port.

I was having issues with this as well. I was using the jdbc connection string to connect to the database. The hostname was incorrectly configured in the string. I am using Mac, and the same string was being used on Windows machines without an issue. On my connection string, I had to make sure that I had the full url with the appending "organizationname.com" to the end of the hostname.
Hope this helps.

Just try to re-create connection. In my situation one of jdbc connection stopped working for no reason. From console sqlplus was working ok.
It took me 2 hours to realize that If i create the same connection - it works.

Connecting to derby via I.P. Address fails

When I print the I.P. address of the system using InetAddress.getLocalHost(), I get user-VAIO/192.168.1.3 . Now, when I connect to derby using jdbc:derby://localhost:1527/mydatabase;create=true, it connects without any errors but when I connect the same using jdbc:derby://192.168.1.3:1527/mydatabase;create=true, it fails giving me the following exception:-
java.net.ConnectException : Error connecting to server 192.168.1.3 on port 1527 with message Connection refused: connect.
Any help will be appreciated.

When you start your Derby Network Server, you provide a value for the '-h' argument. You might not realize you are doing this, if you are using the packaged StartNetworkServer.bat file, but look inside the batch file, and you will see the -h argument there.
The batch file comes provided with the syntax '-h default' when you download Derby from the Apache website.
But you can change that, to say, for example, '-h 192.168.1.3', and then your Derby Network Server will accept connections that specify 'jdbc:derby://192.168.1.3/my/database'.
Note that if you want to accept such connections from other computers on the network, you will also have to adjust your Windows Firewall rules, as by default it will prevent such connections.

java.sql.SQLException encountered when connecting to Oracle database

I get the following error when I try to run my project:
java.sql.SQLException: Io exception: Connection refused(DESCRIPTION=(TMP=)(VSNNUM=169870080)(ERR=12505)(ERROR_STACK=(ERROR=(CODE=12505)(EMFI=4))))
Any ideas?

You're getting an ORA-12505 error ("TNS: listener could not resolve SID given in connection description."). This happens when the SID (System ID) of the database you wish to connect to isn't registered with Oracle's listener. If you can find the JDBC connection information, you may find something that matches this pattern:
jdbc:oracle:thin:[user]/[password]#[host]:[port]:[sid]
In this case, Oracle is telling you that [sid] does not exist on the server [host]. You may be connecting to the wrong server.

Connection refused means that the server is not allowing your client to connect. Double check the server settings and make sure your host is allowed to connect, at the very least.