【转载】监视Tomcat宕机并重启Tomcat

zxg588

下面的代码从网上找的，稍加了点注释。

/**
* 监视Tomcat是否宕机，如果宕机就会自动重启
*/
package cn.ipcat;
import java.net.URL;
import java.net.URLConnection;
import java.util.Date;
public class Detector {
public static void main(String[] args) {
while (true) {
try {
System.out.println(" <" + new Date() + "> 检查服务器是否宕机...");
Detector.keepTomcatAlive();
// 每10分钟执行一次
Thread.sleep(600000);
} catch (Exception ex) {
ex.printStackTrace();
}
}
}
private static void keepTomcatAlive() throws NullPointerException {
String s;
String t = new String("tomcat6.exe");
boolean isTomcatAlive = false;
java.io.BufferedReader in;
try {
URL url = new URL("http://www.ipcat.cn");
URLConnection con = url.openConnection();
in = new java.io.BufferedReader(new java.io.InputStreamReader(con
.getInputStream()));
con.setConnectTimeout(5000);
con.setReadTimeout(10000);
while ((s = in.readLine()) != null) {
if (s.length() > 0) {
// 如果能够读取到页面则证明可用
System.out.println(" <" + new Date() + "> 正常！");
return;
}
}
in.close();
} catch (Exception ex) {
ex.printStackTrace();
}
try {
// 判断任务列表中是否存在tomcat6.exe进程
// 如果存在且不响应，这就表明tomcat已经宕机了，需要重启tomcat
java.lang.Process p = java.lang.Runtime.getRuntime().exec(
"tasklist");
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(
"net stop tomcat2 /y");
java.io.BufferedReader in = new java.io.BufferedReader(
new java.io.InputStreamReader(p.getInputStream()));
String s;
String t = "成功停止";
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 ? "OK" : "ERROR"));
} catch (Exception e) {
e.printStackTrace();
}
}
public static void startTomcat() {
try {
java.lang.Process p = java.lang.Runtime.getRuntime().exec(
"net stop tomcat2 /y");
} catch (Exception e) {
e.printStackTrace();
}
try {
java.lang.Process p = java.lang.Runtime.getRuntime().exec(
"net start tomcat2");
java.io.BufferedReader in = new java.io.BufferedReader(
new java.io.InputStreamReader(p.getInputStream()));
String s;
String t = "启动成功";
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 ? "OK" : "ERROR"));
} catch (Exception e) {
e.printStackTrace();
}
}
}