title: Springboot+JPA(Hibernate)+Oracle AbstractMethodError not define or inherit an implementation of isValid(int)
body: <ul>
  <li>JavaJDK 1.13</li>
  <li>Springboot 2.2.6</li>
  <li>Spring Data JPA</li>
  <li>Oracle 10g</li>
  </ul>
  
  <p>I'm a beginner in using Spring boot, and when I tried running the demo program, it reported exceptions as such:<br>
  <code>Caused by: java.lang.AbstractMethodError: Receiver class oracle.jdbc.driver.T4CConnection does not define or inherit an implementation of the resolved method 'abstract boolean isValid(int)' of interface java.sql.Connection.</code></p>
  
  <p>I've tried many solutions on the web (like upgrade the driver to ojdbc7 or higher, while I've been 
   using ojdbc8 from the begining, and even tried ojdbc8 and ojdbc10 downloading from the website of Oracle 19c, but no one worked).</p>
  
  <p>Following @JensSchauder 's suggestions, I peeked into the class <code>oracle.jdbc.driver.T4CConnection</code> and found there was really no such method called <code>boolean isValid(int)</code> but <code>boolean isValidLight(int)</code> instead.</p>
  
  <p>Here is the screenshoot:<br><a href="https://i.stack.imgur.com/2XAan.png" rel="nofollow noreferrer">ScreenShoot Here, boolean isValidLight(int var1)</a></p>
  
  <p>Here list the ojdbcs I've tried:</p>
  
  <ul>
  <li>ojdbc8:12.2.0.1</li>
  <li>ojdbc7:12.1.0.2</li>
  <li>ojdbc8:19.3.0.0(in use)</li>
  <li>ojdbc10:19.3.0.0</li>
  </ul>
  
  <p>How should I suppose to fix this? Maybe give up Oracle?</p>
  
  <p>Thanks for all your tips.</p>