How to connect to my Heroku PostgreSQL database from Java

Question

I have a Heroku PostgreSQL database to which I can't connect from Java. I have tried different methods but without success.

Below is my Java code:

import java.sql.Connection;
import java.sql.DriverManager;
import java.sql.SQLException;



public class MainConfig {

    public static void main(String[] args) {

     try{
         dataSource();
         System.out.println("conected");
     }
    catch(Exception ex){
        ex.printStackTrace();
    }
    }

    public static Connection dataSource() throws URISyntaxException, SQLException {

        String ConnectionString ="jdbc:postgresql://l********n:cPd7VRjIhNVWOrZ4uWEeZWKYqV@ec2-184-73-251-115.compute-1.amazonaws.com:5432/dac36a93ohuvsd";
        String username = "****";
        String password = "***";

        return DriverManager.getConnection(ConnectionString, username, password);
    }

}

The error I get in console is:

> org.postgresql.util.PSQLException: The connection attempt failed.
    at org.postgresql.core.v3.ConnectionFactoryImpl.openConnectionImpl(ConnectionFactoryImpl.java:233)
    at org.postgresql.core.ConnectionFactory.openConnection(ConnectionFactory.java:64)
    at org.postgresql.jdbc2.AbstractJdbc2Connection.<init>(AbstractJdbc2Connection.java:144)
    at org.postgresql.jdbc3.AbstractJdbc3Connection.<init>(AbstractJdbc3Connection.java:29)
    at org.postgresql.jdbc3g.AbstractJdbc3gConnection.<init>(AbstractJdbc3gConnection.java:21)
    at org.postgresql.jdbc4.AbstractJdbc4Connection.<init>(AbstractJdbc4Connection.java:31)
    at org.postgresql.jdbc4.Jdbc4Connection.<init>(Jdbc4Connection.java:24)
    at org.postgresql.Driver.makeConnection(Driver.java:410)
    at org.postgresql.Driver.connect(Driver.java:280)
    at java.sql.DriverManager.getConnection(Unknown Source)
    at java.sql.DriverManager.getConnection(Unknown Source)
    at MainConfig.dataSource(MainConfig.java:34)
    at MainConfig.main(MainConfig.java:14)
Caused by: java.net.UnknownHostException: lxlrnhejlzmyun:cPd7VRjIhNVWOrZ4uWEeZWKYqV@ec2-184-73-251-115.compute-1.amazonaws.com
    at java.net.AbstractPlainSocketImpl.connect(Unknown Source)
    at java.net.PlainSocketImpl.connect(Unknown Source)
    at java.net.SocksSocketImpl.connect(Unknown Source)
    at java.net.Socket.connect(Unknown Source)
    at org.postgresql.core.PGStream.<init>(PGStream.java:61)
    at org.postgresql.core.v3.ConnectionFactoryImpl.openConnectionImpl(ConnectionFactoryImpl.java:109)
    ... 12 more

I have added to my Build Path the Java driver postgresql-9.3-1102.jdbc41.jar

Another method I have tried for connecting is described bellow with the error message:

    import java.net.URI;
import java.net.URISyntaxException;
import java.sql.Connection;
import java.sql.DriverManager;
import java.sql.SQLException;



public class MainConfig {

    public static void main(String[] args) {

     try{
         dataSource();
         System.out.println("conected");
     }
    catch(Exception ex){
        ex.printStackTrace();
    }
    }

    public static Connection dataSource() throws URISyntaxException, SQLException {
        URI dbUri = new URI(System.getenv("postgres://l**********n:cPd7VRjIhNVWOrZ4uWEeZWKYqV@ec2-184-73-251-115.compute-1.amazonaws.com:5432/dac36a93ohuvsd"));

        String username = dbUri.getUserInfo().split(":")[0];
        String password = dbUri.getUserInfo().split(":")[1];
        String ConnectionString = "jdbc:postgresql://" + dbUri.getHost() + ':' + dbUri.getPort() + dbUri.getPath();



        return DriverManager.getConnection(ConnectionString, username, password);
    }

}

Error

> java.lang.NullPointerException
    at java.net.URI$Parser.parse(Unknown Source)
    at java.net.URI.<init>(Unknown Source)
    at MainConfig.dataSource(MainConfig.java:23)
    at MainConfig.main(MainConfig.java:14)

What I am doing wrong?

Caused by: java.net.UnknownHostException: lxlrnhejlzmyun:cPd7VRjIhNVWOrZ4uWEeZWKYqV@ec2-184-73-251-115.compute-1.amazonaws.com. Have you verified the host details ? — gvmani, Aug 02 '14 at 13:41
Possible duplicate of [Connecting to Heroku Postgres from Spring Boot](https://stackoverflow.com/questions/33633243/connecting-to-heroku-postgres-from-spring-boot) — Vic Seedoubleyew, May 13 '19 at 15:14

Arctelix · Answer 1 · 2015-12-27T06:23:12.523

Inorder to connect to heroku's PostgreSQL (with the required ssl) you must append the following to the url:

?ssl=true&sslfactory=org.postgresql.ssl.NonValidatingFactory

So the correct url as provided in the answer above is:

jdbc:postgresql://host:port/database?ssl=true&sslfactory=org.postgresql.ssl.NonValidatingFactory

Without these perimeters you will get the error described:

error: no pg_hba.conf entry for host

score 4 · Accepted Answer · edited Apr 19 '19 at 19:57

4

The format should be: jdbc:postgresql://host:port/database, whereas in your code its is, note couple of ':' jdbc:postgresql://l********n:cPd7VRjIhNVWOrZ4uWEeZWKYqV@ec2-184-73-251-115.compute-1.amazonaws.com:5432/dac36a93ohuvsd"

edited Apr 19 '19 at 19:57

Lebron11

656
7
18

answered Aug 02 '14 at 13:44

gvmani

1,580
1
12
20

Thank u, I modified the connection string I now i get the error: no pg_hba.conf entry for host "92.82.172.24", user "***", database "***". I mention that I have inserted the line into pg**.conf and restarted the system # TYPE DATABASE USER ADDRESS METHOD # IPv4 local connections: host all all *********/32 md5 host ************** ********** 92.82.172.24/32 md5 – SocketM Aug 02 '14 at 14:41
@SocketM check this --> http://stackoverflow.com/questions/17377118/heroku-database-connection-properties – gvmani Aug 02 '14 at 15:01
Thank u, I give up with Heroku. I dont't understand how to set up SSL to true. I will use my local database and I will import to another station with SQL query. – SocketM Aug 03 '14 at 09:14

score 0 · Answer 3 · answered Jul 28 '18 at 12:12

0

your url should look like - jdbc:postgresql://hostname:port/dbname?sslmode=require

copy hostname(Host) port and dbname(Database) as mentioned in heroku site

Dont forget to append ?sslmode=require in your url otherwise u won't get connected

answered Jul 28 '18 at 12:12

Sourav Purohit

101
1
3

How to connect to my Heroku PostgreSQL database from Java

3 Answers3

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