本文实例讲述了JAVA实现监测tomcat是否宕机及控制重启的方法。分享给大家供大家参考。具体如下：

Detector.java:

import java.net.URL; import java.net.URLConnection; import java.util.Date; /** * * @author james * */ public class Detector { private static void keepTomcatAlive() throws NullPointerException { String s; String t = new String("tomcat6"); boolean isTomcatAlive = false; java.io.BufferedReader in; System.setProperty("sun.net.client.defaultConnectTimeout", "8000"); System.setProperty("sun.net.client.defaultReadTimeout", "10000"); try { URL url = new URL("http://localhost:8080/test.jsp"); URLConnection con = url.openConnection(); in = new java.io.BufferedReader(new java.io.InputStreamReader(con.getInputStream())); con.setConnectTimeout(1000); con.setReadTimeout(4000); while ((s = in.readLine()) != null) { if (s.length() > 0) { //accessed page successful. return; } } in.close(); } catch (Exception ex) { //ex.printStackTrace(); } try { java.lang.Process p = java.lang.Runtime.getRuntime().exec("ps -aux"); in = new java.io.BufferedReader(new java.io.InputStreamReader(p.getInputStream())); while ((s = in.readLine()) != null) { if (s.startsWith(t)) { isTomcatAlive = true; break; } } in.close(); }catch (Exception e) { e.printStackTrace(); } if (isTomcatAlive) { System.out.println("<" + new Date() + "> Tomcat is alive but not response!"); stopTomcat(); } startTomcat(); } public static void stopTomcat() { try { java.lang.Process p = java.lang.Runtime.getRuntime().exec("/etc/init.d/tomcat6 stop"); java.io.BufferedReader in = new java.io.BufferedReader(new java.io.InputStreamReader(p.getInputStream())); String s; String t = "Stopping"; boolean restart = false; while ((s = in.readLine()) != null) { if (s.indexOf(t) != -1) { restart = true; break; } } System.out.println("<" + new Date() + "> Tomcat is stop " + (restart ")); } catch (Exception e) { e.printStackTrace(); } } public static void startTomcat() { try { java.lang.Process p = java.lang.Runtime.getRuntime().exec("/etc/init.d/tomcat6 start"); java.io.BufferedReader in = new java.io.BufferedReader(new java.io.InputStreamReader(p.getInputStream())); String s; String t = "Starting"; boolean restart = false; while ((s = in.readLine()) != null) { if (s.indexOf(t) != -1) { restart = true; break; } } System.out.println("<" + new Date() + "> Tomcat is start " + (restart ")); } catch (Exception e) { e.printStackTrace(); } } private static void debug(String msg){ System.out.println("Debug::: "+msg); } public static void main(String[] args) { while (true) { try { debug("Detect agin <"+new Date()+">"); Detector.keepTomcatAlive(); debug("Sleep..."); Thread.sleep(30000); } catch (Exception ex) { ex.printStackTrace(); } } } }

希望本文所述对大家的java程序设计有所帮助。