SQLException " Unsupported major.minor version 52.0" when connecting to a JDBC database

SYMPTOM

When connecting to a JDBC database, an error message similar to the following ones is displayed.

Example 1:

java.lang.UnsupportedClassVersionError: org/postgresql/Driver : Unsupported major.minor version 52.0
 at java.lang.ClassLoader.defineClass1(Native Method)
 at java.lang.ClassLoader.defineClass(ClassLoader.java:791)
 at java.security.SecureClassLoader.defineClass(SecureClassLoader.java:142)
 at java.net.URLClassLoader.defineClass(URLClassLoader.java:449)
 at java.net.URLClassLoader.access$100(URLClassLoader.java:71)
 at java.net.URLClassLoader$1.run(URLClassLoader.java:361)
 at java.net.URLClassLoader$1.run(URLClassLoader.java:355)
 at java.security.AccessController.doPrivileged(Native Method)
 at java.net.URLClassLoader.findClass(URLClassLoader.java:354)
 at java.lang.ClassLoader.loadClass(ClassLoader.java:423)
 at java.lang.ClassLoader.loadClass(ClassLoader.java:356)
 at java.lang.Class.forName0(Native Method)
 at java.lang.Class.forName(Class.java:188)

Example 2:

Caused by: java.lang.UnsupportedClassVersionError: com/mysql/cj/jdbc/Driver : Unsupported major.minor version 52.0
at java.lang.ClassLoader.defineClass1(Native Method)
at java.lang.ClassLoader.defineClass(Unknown Source)
at java.security.SecureClassLoader.defineClass(Unknown Source)
at java.net.URLClassLoader.defineClass(Unknown Source)
at java.net.URLClassLoader.access$100(Unknown Source)
at java.net.URLClassLoader$1.run(Unknown Source)
at java.net.URLClassLoader$1.run(Unknown Source)
at java.security.AccessController.doPrivileged(Native Method)
at java.net.URLClassLoader.findClass(Unknown Source)
at java.lang.ClassLoader.loadClass(Unknown Source)
at java.lang.ClassLoader.loadClass(Unknown Source)
at java.lang.Class.forName0(Native Method)
at java.lang.Class.forName(Unknown Source)
at org.apache.commons.dbcp.BasicDataSource.createConnectionFactory(BasicDataSource.java:1415)

Solution

Check if your Java version and JDBC driver version are compatible by using the database documentation.

For example:
Postgresql: https://jdbc.postgresql.org/download.html
MySQL: https://dev.mysql.com/doc/connector-j/5.1/en/connector-j-versions.html

Error when working with File: FileDriverStatement::executeQuery, error opening the file

Symptom

When working with a File metadata (executing a read or write mapping, replicate File to rdbms...) the following error occurs :

Error: FileDriverStatement::executeQuery, error opening the file \\servername\d$\Data\IN\CUSTOMER-20180808-134523.txt

The file is located on a shared drive.

Solution

This is generally due to permission issues.

• Verify that the user which runs the Runtime has permission on the shared drive
• Alternatively, share the folder instead of the drive : \\servername\IN\...

SSH Action does not load environment variables

Symptom

When executing a SSH command with the "Execute SSH" Action, some environment variables are not loaded / initialized.

It seems that the SSH session does not load the Linux user's environment or profile.

Solution

The Execute SSH action opens a non-interactive shell session on the remote server. With this kind of session, the shell does not load the user's environement and profile scripts (see documentation for bash for example), this is why some environment variables are not available.

Simple test to confirm this case: compare the result of the "set" command in your prefered Terminal application and in the output of Stambia's Execute SSH.

A simple way to load environment variables is to source a config file at the beginning of your Execute SSH action Code:

source /home/user/some_config.sh
echo "$myvar is set"
start_something.sh -o "${~/param}$"

Error "Failed to parse with generic parser" when executing a mapping

Symptom

When executing a mapping (or a process containing a mapping), the following error occurs on a SQL Operation action: "Failed to parse with generic parser".

Solution

• If one of the column names starts with a number then enclose this column name with delimiters in the mapping expression, such as this Sql Server example (adapt it to your database):

• If no column starts with a number then contact support