CodeJava.net • Home • Java Core • The Java Language • Generics & Collections • Tools • Exception Handling • Concurrency • Java SE • Swing • Applet • File I/O • 2D/3D Graphics • Networking • FTP • JDBC • Java EE • Servlet • JavaMail • Web Services • JSTL • JavaServer Pages (JSP) • Java Persistence API • Frameworks • Spring • Spring Boot • Hibernate • Struts • IDEs • Eclipse • NetBeans • Servers • Tomcat • Coding • Books • Videos • Top Trending • Top Java Core and Java EE • Top Spring and Hibernate • Interview Questions • Certifications • Testing. Basically, an installation of Tomcat is running under the default JRE which can be found based on environment variables ( JAVA_HOME), or registry entries (on Windows) or the JRE is specified during installation (Tomcat is installed as a service). Sometimes we need to change the default JRE for Tomcat, either for testing purposes or to run Tomcat under a targeted version of JRE.

In this article, we summarize different ways to change JRE for a Tomcat installation.To know which JRE version is used for Tomcat, go to the following URL: localhost:8080/manager/statusAnd look at the JVM Version column: 1. Changing JRE by updating JAVA_HOME or JRE_HOMEThis way is very simple to implement but it works only for Tomcat installed from a zip distribution (in contrast to Tomcat installed as a service). • • If only the JAVA_HOME environment variable is set, Tomcat will run under the JRE as part of the JDK specified by the JAVA_HOME variable. Therefore, we change JRE for Tomcat by updating this variable. • If both the JAVA_HOME and JRE_HOME environment variables are set, the JRE_HOME is preferred. Here’s an example of a valid value for the JRE_HOME variable (path on Windows): JRE_HOME=C: Program Files Java jre7Notice that updating the JAVA_HOME or JRE_HOME environment variables will affect all the applications that depend on them, so if you want to look for a more independent approach, see the second way as described below.

Changing JRE by using “setenv” scriptWe can change the JRE for Tomcat by setting the JRE_HOME variable in a script file called setenv.bat (on Windows) or setenv.sh (on *nix). Piano and keyboard method torrent mac torrenting. This file does not exist by default, so create such file and place it under CATALINA_BASE bin directory ( CATALINA_BASE is the Tomcat installation directory). On Windows, create the setenv.bat file with the following content: set 'JRE_HOME=C: Program Files Java jdk1.7.0_03 jre' exit /b 0On *nix, create the setenv.sh file with the following content: JRE_HOME=/usr/java/jdk1.7.0_03/jre CATALINA_PID='$CATALINA_BASE/tomcat.pid'Note that this way only works with Tomcat installed from a zip distribution. It doesn’t apply for Tomcat installed as a service. Behind the scenes, the Tomcat’s start up script ( startup.bat/ startup.sh) will invoke the “setenv” script if it is present. One advantage of this way is that it doesn’t affect the system environment variables. Changing JRE in Tomcat service managerFor a Tomcat installation which is installed as a service (on Windows), we can change the version of JRE that runs Tomcat by configuring the Java Virtual Machine setting in the Tomcat service manager program (e.g.