Java AWS EC2实例：启动多个实例
我想在新用户到达时创建ec2实例。为此，我创建了一个servlet类。当用户到达时，我检查数据库是否是用户新的，如果是新的，则创建实例并发回他/她的IP。当我为用户逐个向这个servlet发送http请求时，我正确地获得了IP。但当我并行发送HTTP调用时（对于tab1中的user1发送请求，对于tab2中的user2发送请求，在从user1 HTTP调用获得响应之前同时发送）。当我这样做的时候，我犯了一个错误。有时候用户1说 “实例ID‘i-0b79495934c3b5459’不存在（服务： AmazonEC2；状态代码：400；错误代码：InvalidInstanceID.NotFound； 请求ID:e18a9eaa-cb1b-4130-a3ee-bf1b19fa184c） 用户2发送IP作为响应。请帮助我什么是问题以及如何解决这个问题。 这是我创建的Servlet类Java AWS EC2实例：启动多个实例,java,amazon-web-services,servlets,amazon-ec2,aws-sdk,Java,Amazon Web Services,Servlets,Amazon Ec2,Aws Sdk,我想在新用户到达时创建ec2实例。为此，我创建了一个servlet类。当用户到达时，我检查数据库是否是用户新的，如果是新的，则创建实例并发回他/她的IP。当我为用户逐个向这个servlet发送http请求时，我正确地获得了IP。但当我并行发送HTTP调用时（对于tab1中的user1发送请求，对于tab2中的user2发送请求，在从user1 HTTP调用获得响应之前同时发送）。当我这样做的时候，我犯了一个错误。有时候用户1说 “实例ID‘i-0b79495934c3b5459’不存在（服务：
public class GateKeeperController extends HttpServlet {
private static final long serialVersionUID = 1L;
BasicAWSCredentials awsCreds = new BasicAWSCredentials(credentials);
AmazonEC2Client ec2Client = new AmazonEC2Client(awsCreds);
RunInstancesRequest runInstancesRequest;
RunInstancesResult runInstancesResult;
Reservation reservation;
Instance intstance;
DescribeInstancesRequest describeInstanceRequest;
DescribeInstancesResult describeInstanceResult;
GatekeeperModal gateKeepermodal;
String sourceAMI = null;
String destinationAMI = null;
protected void doGet(HttpServletRequest request, HttpServletResponse response)
throws ServletException, IOException {
HttpSession s = request.getSession();
String userID = (String) request.getParameter("userID");
Double lattitude = Double.parseDouble((String) request.getParameter("lat"));
Double lonitude = Double.parseDouble((String) request.getParameter("long"));
if (userID != null) {
Pair coordinates = new Pair(lattitude, lonitude);
RegionSelection targetRegion = new RegionSelection();
String regionResult = targetRegion.getRegion(coordinates);
String instanceIP = null;
gateKeepermodal = new GatekeeperModal();
try {
if (gateKeepermodal.checkUserIsNew(userID)) {
instanceIP = startInstance(userID, regionResult);
if (instanceIP != null) {
response.getWriter().write(instanceIP);
}
}
} catch (SQLException e) {
// TODO Auto-generated catch block
e.printStackTrace();
}
} else {
}
}
private String startInstance(String userID, String region) {
String ami_id = new AMI().getAMI_ID(region);
ec2Client.setEndpoint(region);
runInstancesRequest = new RunInstancesRequest();
runInstancesRequest.withImageId(ami_id).withInstanceType("t2.micro").withMinCount(1).withMaxCount(1)
.withKeyName("GateKeeper_User").withSecurityGroups("GateKeeper User");
runInstancesResult = ec2Client.runInstances(runInstancesRequest);
reservation = runInstancesResult.getReservation();
intstance = reservation.getInstances().get(0);
String s1 = intstance.getState().getName();
String s2 = InstanceStateName.Running.name();
while (!s1.toLowerCase().equals(s2.toLowerCase())) {
describeInstanceRequest = new DescribeInstancesRequest();
describeInstanceRequest.withInstanceIds(intstance.getInstanceId());
ec2Client.setEndpoint(region);
describeInstanceResult = ec2Client.describeInstances(describeInstanceRequest);
reservation = describeInstanceResult.getReservations().get(0);
intstance = reservation.getInstances().get(0);
s1 = intstance.getState().getName();
s2 = InstanceStateName.Running.name();
}
GateKeeperUser user = new GateKeeperUser(userID, intstance.getInstanceId(), intstance.getPublicIpAddress(),
region);
Boolean result;
try {
result = gateKeepermodal.createUser(user);
if (result) {
return intstance.getPublicIpAddress();
} else {
return null;
}
} catch (SQLException e) {
}
return null;
}
}