Recently I finished migrating my application from Java 8 to OpenJDK 11. Here are few steps where we got stuck and the solutions that helped us.
Problem No 1 – JVM argument UseFastAccessorMethods argument is not supported anymore in OpenJDK 11
Solution – Removed this JVM argument from batch scripts/shell scripts.
Further Reading – https://bugs.java.com/bugdatabase/view_bug.do?bug_id=6385687
Problem No 2 – com.myApp.configuration.Module class conflicts with java.lang.Module class introduced in OpenJDK 11. Basically I had a class called Module which was now conflicting with java.lang.Module class introduced in OpenJDK 11.
Solution – Explicitly import com.myApp.configuration.Module class in required classes.
Further Reading – https://docs.oracle.com/javase/9/docs/api/java/lang/class-use/Module.html
Problem No 3 – Compile/Runtime issues with commons-lang:commons-lang:2.1@jar
Solution – Upgraded to commons-lang:commons-lang:2.6@jar
Problem No 4
Jersey Rest APIs were not working (Runtime issue) with following libraries
‘org.glassfish.jersey.core:jersey-client:2.16@jar’
‘org.glassfish.jersey.core:jersey-common:2.16@jar’
‘org.glassfish.jersey.containers:jersey-container-servlet:2.16@jar’
‘org.glassfish.jersey.containers:jersey-container-servlet-core:2.16@jar’
‘org.glassfish.jersey.bundles.repackaged:jersey-guava:2.16@jar’
‘org.glassfish.jersey.media:jersey-media-jaxb:2.16@jar’
‘org.glassfish.jersey.core:jersey-server:2.16@jar’
Solution
Migrated these libraries to below libraries. Post this upgrade Jersey APIs were working fine ‘org.glassfish.jersey:jersey-bom:2.27’
‘org.glassfish.jersey.containers:jersey-container-servlet:2.27’
‘org.glassfish.jersey.inject:jersey-hk2:2.27’
‘org.glassfish.jersey.core:jersey-client:2.27’
‘org.glassfish.jersey:jersey-bom:2.27’
‘org.glassfish.jersey.containers:jersey-container-servlet:2.27’
‘org.glassfish.jersey.inject:jersey-hk2:2.27’
‘org.glassfish.jersey.core:jersey-client:2.27’
Problem No 5 – Library com.sun.xml.messaging.saaj missing in OpenJDK 11 which was part of Oracle Java 8. This is used in SOAP
Solution – Explicity import library ‘com.sun.xml.messaging.saaj:saaj-impl:1.3.20’
Further Reading – https://javaee.github.io/metro-saaj/
Problem No 6 – Library com.sun.org.apache.xml.internal:resolver missing in OpenJDK 11 which was part of Oracle Java 8.
Solution – Explicitly import library compile group: ‘com.sun.org.apache.xml.internal’, name: ‘resolver’, version: ‘20050927’
Further Reading – https://stackoverflow.com/questions/3889308/xml-catalog-resolving-resolver-jar-vs-com-sun-org-apache-xml-internal-resolver
Problem No 7 – Gradle compilation fails since JAVA_HOME was pointing to older Oracle Java 8 JDK
Solution – Changed JAVA_HOME environment variable to point to new OpenJDK 11
Problem No 8 – Tomcat was not starting since JRE_HOME was pointing to older Oracle Java 8 JDK
Solution – There is no JRE in OpenJDK 11. So we have to remove JRE_HOME variable
I encountered few more problems, will list the solutions soon on this page for those as well. I have tested my application on Windows 10 and CentOS 6 and 7.
