<Resource name="jdbc/testdb" auth="Container" type="javax.sql.DataSource"
          username="test" password="test1234"
          url="*********"
          driverClass="oracle.jdbc.driver.OracleDriver"
          initialSize="5" maxWait="5000"
          maxActive="120" maxIdle="5"
          validationQuery="select 1"
          poolPreparedStatements="true"/>

<Resource name="jdbc/testdb" auth="Container" type="javax.sql.DataSource"
          username="test" password="test1234"
          url="*********"
          driverClass="oracle.jdbc.driver.OracleDriver"
          initialSize="5" maxWait="5000"
          maxActive="120" maxIdle="5"
          validationQuery="select 1"
          poolPreparedStatements="true"/>

<ResourceLink name="jdbc/testdb" global="jdbc/testdb"
type="javax.sql.DataSource" />

<jee:jndi-lookup id="dataSource" jndi-name="jdbc/testdb"  resource-ref="true" />

<resource-ref>
       <description>Resource reference to database</description>
       <res-ref-name>jdbc/testdb</res-ref-name>
       <res-type>javax.sql.DataSource</res-type>
       <res-auth>Container</res-auth>
       <res-sharing-scope>Shareable</res-sharing-scope>
</resource-ref>

Error querying database.  Cause: org.springframework.jdbc.CannotGetJdbcConnectionException: Could not get JDBC Connection; nested exception is org.apache.tomcat.dbcp.dbcp.SQLNestedException: Cannot create JDBC driver of class '' for connect URL 'null'

driverClassName="oracle.jdbc.driver.OracleDriver"

<!-- dependency>
       <groupId>org.postgresql</groupId>
       <artifactId>postgresql</artifactId>
       <scope>runtime</scope>
    </dependency-->

<GlobalNamingResources>
 ...
   <Resource name="jdbc/postgres_jndi"
              auth="Container"
              type="javax.sql.DataSource"
              driverClassName="org.postgresql.Driver"
              url="jdbc:postgresql://xxx.xxx.xx.xxx:5432/db"
              factory="org.apache.tomcat.jdbc.pool.DataSourceFactory"
              removeAbandonedOnBorrow="true"
              removeAbandonedOnMaintenance="true"
              timeBetweenEvictionRunsMillis="10000"
              removeAbandonedTimeout="60"
              logAbandoned="true"
              username="xxx"
              password="xxxxxx"
              maxTotal="20"
              maxIdle="10"
              maxWaitMillis="-1"/>
 ...
</GlobalNamingResources>

spring:
  datasource:
    platform: postgres
    jndi-name: java:comp/env/jdbc/postgres_jndi
    type: javax.sql.DataSource
    driver-class-name: org.postgresql.Driver
  jpa:
    hibernate:
      ddl-auto: validate
    database-platform: org.hibernate.dialect.PostgreSQL9Dialect
    database: POSTGRESQL
    show-sql: true
    #Method org.postgresql.jdbc.PgConnection.createClob() is not yet implemented.
    properties:
      hibernate:
        temp:
          use_jdbc_metadata_defaults: false

spring.datasource.platform= postgres
    spring.datasource.jndi-name= java:comp/env/jdbc/postgres_jndi
    spring.datasource.type= javax.sql.DataSource
    spring.datasource.driver-class-name= org.postgresql.Driver
    spring.jpa.hibernate.ddl-auto= validate
    spring.jpa.hibernatedatabase-platform= org.hibernate.dialect.PostgreSQL9Dialect
    spring.jpa.database= POSTGRESQL
    spring.jpa.show-sql= true
    spring.jpa.properties.hibernate.temp.use_jdbc_metadata_defaults=false

<?xml version="1.0" encoding="UTF-8"?>
<Context path="/myapp">
    <ResourceLink global="jdbc/postgres_jndi" name="jdbc/postgres_jni" type="javax.sql.DataSource"/>
</Context>