"no JDK found – please set JAVA_HOME" while starting tomcat7

Solution 1 to make sure default-java exists underneath /usr/lib/jvm/ folder,if no, you can do something as follow:

ln -s /usr/lib/jvm/java-7-oracle /usr/lib/jvm/default-java

Solution 2 Add JAVA_HOME variable into /etc/default/tomcat7 file to specific JDK for tomcat7

sudo gedit /etc/default/tomcat7

Added JAVA_HOME variable

JAVA_HOME=/usr/lib/jvm/java-7-oracle

Reference:

• Specify JDK for tomcat7

• Error starting Tomcat7 “no JDK found – please set JAVA_HOME”