Eclipse JDK8 to JDK11 Issue: Package is accessible from more than one module

[MK07]

• Error after changing Java from java 1.8 to Java 11.
• The package org.w3c.dom is accessible from more than one module: <unnamed>, java.xml.
• Module path is not used.
• below class files are imported, but errors occurring
  import javax.xml.XMLConstants;
  import org.w3c.dom.Document;
• The package javax.xml is accessible from more than one module: <unnamed>, java.xml

[VladimirN · Accepted solution]

Some old discussion - "Eclipse JDK8 to JDK11 Issue: Package is accessible from more than one module": https://community.ptc.com/t5/Windchill/Eclipse-JDK8-to-JDK11-Issue-Package-is-accessible-from-more-than/td-p/686246