In order to run Stored Procedure Builder on AIX or Solaris, you need to ensure that you have a Java Development Kit (JDK) installed on your system. DB2 installs a Java Run-Time Environment (JRE) on your system which can be used for the Control Center, however, it will not allow you to use Stored Procedure Builder.
Once you have installed your JDK, you need to ensure that DB2 is aware of location of the JDK by setting its path in the instance's database manager configuration file. To set the JDK's path, perform the following steps:
db2 update dbm cfg using jdk11_path /usr/java
where /usr/java represents the JDK installation path.
db2stop db2start