gistfile1.java

VirtualMachine vm = VirtualMachine.attach("7851");
String javaHome = vm.getSystemProperties().getProperty("java.home");
String agentJar = javaHome + File.separator +  "lib" + File.separator + "management-agent.jar";
vm.loadAgent(agentJar, "com.sun.management.jmxremote");
String localConnectorAddress = vm.getAgentProperties().getProperty("com.sun.management.jmxremote.localConnectorAddress");
if (localConnectorAddress == null) {
    // Check system properties
    localConnectorAddress = vm.getSystemProperties().getProperty("com.sun.management.jmxremote.localConnectorAddress");
}
vm.detach();

JMXServiceURL jmxURL = new JMXServiceURL(localConnectorAddress);
JMXConnector connector = JMXConnectorFactory.connect(jmxURL);
MBeanServerConnection mbsc = connector.getMBeanServerConnection();

ObjectName hostObjectName = new ObjectName("Catalina:type=Host,host=localhost");
mbsc.invoke(hostObjectName, "stop", null, null);
mbsc.invoke(hostObjectName, "start", null, null);

connector.close();