Background: During the Spring Festival, the server always disconnects the database connection suddenly, and always has to restart tomcat manually. This is really a chore. I can't solve the problem on the database, so I just write something for regular detection. restart works.
Server environment: Windows2003 service
tomcat version: tomcat6
Java version: jdk6
At first, I wanted to use Java to do this work. The idea is to link the url regularly. If the returned value is not 200, then close tocmat and restart it.
code show as below:
import java.io.File;
import java.io.IOException;
import java.net.HttpURLConnection;
import java.net.MalformedURLException;
import java.net.URL;
import java.text.SimpleDateFormat;
import java.util.Date;
/**
* 用户 ：LX
* 创建时间： 2018/2/23. 14:57
* 地点：广州
* 目的: 定时检查系统是否挂掉
* 结果：
*/
public class TaskCheck {
/**
* 访问的URL地址
*/
private static final String URLVISIT = "要检查的url地址";
public static void main(String[] args) {
TaskCheck taskCheck = new TaskCheck();
while (1 == 1){
System.out.println(taskCheck.getDate() + "=====================开始检测系统状态====================================");
if (!taskCheck.checkGSSurvival()){
taskCheck.stopTomcat();
try {
System.out.println("关闭tomcat·············");
Thread.sleep(10000);
} catch (InterruptedException e) {
e.printStackTrace();
}
//重启tomcat
System.out.println("正在重启tomcat·············");
taskCheck.startTomcat();
} else {
}
System.out.println(taskCheck.getDate() + "==============================系统检测结束==============================");
try {
Thread.sleep(1000 * 60 * 5);
} catch (InterruptedException e) {
e.printStackTrace();
}
}
}
/**
* 启动tomcat
*/
public void startTomcat(){
Runtime run = Runtime.getRuntime();
String[] envp = { //环境变量设置
"JAVA_HOME=C:\\Java\\jdk1.6.0_45", //Ant
"CATALINA_HOME=E:\\apache-tomcat-7.0.47" //Tomcat
};
try {
// 启动另一个进程来执行命令
Process p = run.exec("E:\\apache-tomcat-7.0.47\\bin\\startup.bat", envp, new File("E:\\apache-tomcat-7.0.47"));
} catch (IOException e) {
e.printStackTrace();
}
}
/**
* 停止tomcat
*/
public void stopTomcat() {
Runtime run = Runtime.getRuntime();
String[] envp = { //环境变量设置
"JAVA_HOME=C:\\Java\\jdk1.6.0_45", //Ant
"CATALINA_HOME=E:\\apache-tomcat-7.0.47" //Tomcat
};
try {
// 启动另一个进程来执行命令
Process p = run.exec("E:\\apache-tomcat-7.0.47\\bin\\shutdown.bat", envp, new File("E:\\apache-tomcat-7.0.47"));
} catch (IOException e) {
e.printStackTrace();
}
}
/**
* 检查系统是否还存活
* @return true 还存活， false 已经关闭
*/
public boolean checkGSSurvival(){
boolean result = true;
for (int i = 0; i < 3; i ++){
try {
URL url = new URL(URLVISIT);
HttpURLConnection httpURLConnection = (HttpURLConnection) url.openConnection();
// 设定传送的内容类型是可序列化的java对象
// (如果不设此项,在传送序列化对象时,当WEB服务默认的不是这种类型时可能抛java.io.EOFException)
httpURLConnection.setRequestProperty("Content-type", "application/x-java-serialized-object");
//setConnectTimeout：设置连接主机超时（单位：毫秒）
httpURLConnection.setConnectTimeout(20000);
//setReadTimeout：设置从主机读取数据超时（单位：毫秒）
httpURLConnection.setReadTimeout(20000);
httpURLConnection.connect();
//可以获取状态码
System.out.println(httpURLConnection.getResponseCode());
if (200 == (httpURLConnection.getResponseCode())){
System.out.println("系统运行正常！");
return true;
} else {
System.out.println("异常！" + getDate());
result = false;
}
//休眠10秒
Thread.sleep(10000);
} catch (MalformedURLException e) {
e.printStackTrace();
System.err.println("打开系统失败================================================" + getDate());
result = false;
} catch (IOException e) {
e.printStackTrace();
System.err.println("访问系统打开失败================================================" + getDate());
result = false;
} catch (InterruptedException e) {
e.printStackTrace();
result = false;
}
}
return result;
}
/**
* 获取时间
* @return
*/
public String getDate(){
Date date = new Date();
SimpleDateFormat dateFormat= new SimpleDateFormat("yyyy-MM-dd :hh:mm:ss");
return dateFormat.format(date);
}
}
The ones found on the Internet are basically on Linux systems, and the writing methods are somewhat different. The Java above is based on Windows servers, and it is no problem to test locally. The main point is that, first: the environment variables should be passed in the code. Go in, otherwise it may lead to tomcat can not be started, second, to set the environment variables, tomcat and Java
There is no problem with the above code in the local test, but the official environment of running calls the command to close tomcat, but it cannot be closed. I don’t know what the reason is. I really don’t want to see the relevant code in Java. It’s too unfriendly. And look at Python, Python is simple and convenient, just use Python, the code is as follows:
import webbrowser
import requests
import datetime
import time
# tomcat的启动路径
tomcatStart = "E:\\apache-tomcat-7.0.47\\bin\\startup.bat"
# tomcat的关闭路径
tomcatStop = "E:\\apache-tomcat-7.0.47\\bin\\shutdown.bat"
# 要检查的url
url = "要检查的url"
# 启动tomcat
def startTomcat():
webbrowser.open("file:///" + tomcatStart)
# 关闭tomcat
def stopTomcat():
webbrowser.open("file:///" + tomcatStop)
# 终止tomcat进程，如果系统只有一个tomcat在运行，没其他的Java程序在跑的话，用这个可以快速关掉进程，该方式是在上面这种情况还关闭不了的情况下使用的
# os.system("taskkill /F /IM java.exe")
# 检查系统是否还存活 true 还存活， false 已经关闭
def checkWeb():
i = 0
for i in range(3):
try:
i = i + 1
result = True
headers = {
'User-Agent': 'Mozilla/5.0 (Windows NT 6.1; WOW64) AppleWebKit/537.36 (KHTML, like Gecko) Chrome/35.0.1916.153 Safari/537.36 SE 2.X MetaSr 1.0'}
response = requests.get(url, timeout = 10) #请求超时时间为10秒
# encode = response.encoding #从http header 中猜测的相应内容编码方式
code = response.status_code #http请求的返回状态，若为200则表示请求成功,返回的状态码是 int类型
print(str(getDate()) + " 检测到状态编码：" + str(code))
if code == 200:
result = True
else:
result = False
time.sleep(5) #休眠5秒
except:
result = False
return result
# 获取时间
def getDate():
today = datetime.date.today()
return today
def mainApp():
while True:
print(str(getDate()) + " =========开始检测系统状态=============")
if checkWeb() == False:
print(str(getDate()) + " 系统异常中·············")
print("=====开始停止tomcat，等待75秒··====")
stopTomcat()
time.sleep(75) # 休眠75秒来关闭应用,系统应用在服务器上关闭有点慢
print("=====正在重启tomcat====")
startTomcat()
else:
print(str(getDate()) + " ***系统正常***")
print(str(getDate()) + " =========结束检测系统状态=============")
time.sleep(60 * 3) # 休眠3分钟
mainApp()
The code is as simple as the above, you may not want to install the Python environment on the server, and simply make it into an exe package
After pip installs the module pyinstaller, run python pyinstaller.py -F package name.py directly,
exe file came out
Put it on the server and run it, the effect is as follows
Note: If there is still a situation where the tomcat process cannot be closed, you can use the method of directly killing the process. This method is only suitable for when only one tomcat is running and no other Java programs are running. When using it, release the code comment and comment above. The code that calls tocmat automatically closes there.
update：2018.2.27 =========================================
I just had time to look at Python in the past two days. I feel that the above code can be optimized again, and it can be automatically restarted and closed for multiple tomcats.
code show as below:
import os
"""
根据端口获取PID
返回获取的PID
"""
def getPID(port):
try:
# 根据命令获取到指定端口的信息 TCP 0.0.0.0:8080（端口） 0.0.0.0:0 LISTENING 6856（PID）
ret = os.popen("netstat -nao | findstr " + port)
str_list = ret.read()
print(str_list)
# 字符串按空格分成列表split()
ret_list = str_list.split()
# 截取出pid
pid = ret_list[4][:6]
print(type(pid))
return pid
except:
print("根据端口找不到该对应应用")
return "0"
"""
# 根据PID杀死进程
"""
def kill(pid):
try:
os.popen('taskkill.exe /pid:' + str(pid))
print("已经杀死PID为 " + pid + " 的进程")
except OSError:
print('没有如此进程!!!')
errorStr = OSError.errno
print("错误信息" + errorStr)
if __name__ == '__main__':
pid = getPID("8080")
print(pid)
if pid == "0":
print("没有需要删除的进程")
else:
kill(pid)
Only the key code is given here, and other things can basically be spelled out by yourself. The idea is as follows:
Always monitor whether the website is normal. If it is abnormal, then go to get the PID under the specified port, so that you can get the PID of the tomcat process, then close the application according to the PID, and then restart, this way of writing can basically satisfy various demand