server/src/main/java/com/cloud/servlet/CloudStartupServlet.java

// Licensed to the Apache Software Foundation (ASF) under one
// or more contributor license agreements.  See the NOTICE file
// distributed with this work for additional information
// regarding copyright ownership.  The ASF licenses this file
// to you under the Apache License, Version 2.0 (the
// "License"); you may not use this file except in compliance
// with the License.  You may obtain a copy of the License at
//
//   http://www.apache.org/licenses/LICENSE-2.0
//
// Unless required by applicable law or agreed to in writing,
// software distributed under the License is distributed on an
// "AS IS" BASIS, WITHOUT WARRANTIES OR CONDITIONS OF ANY
// KIND, either express or implied.  See the License for the
// specific language governing permissions and limitations
// under the License.
package com.cloud.servlet;

import java.util.Timer;
import java.util.TimerTask;

import javax.servlet.ServletConfig;
import javax.servlet.ServletException;
import javax.servlet.http.HttpServlet;

import org.springframework.web.context.support.SpringBeanAutowiringSupport;

import com.cloud.utils.LogUtils;
import com.cloud.utils.SerialVersionUID;
import com.cloud.utils.component.ComponentContext;
import com.cloud.utils.db.TransactionLegacy;

public class CloudStartupServlet extends HttpServlet {
    static final long serialVersionUID = SerialVersionUID.CloudStartupServlet;

    Timer _timer = new Timer();

    @Override
    public void init(ServletConfig config) throws ServletException {
        LogUtils.initLog4j("log4j-cloud.xml");
        SpringBeanAutowiringSupport.processInjectionBasedOnServletContext(this, config.getServletContext());

        // wait when condition is ready for initialization
        _timer.scheduleAtFixedRate(new TimerTask() {
            @Override
            public void run() {
                if (ComponentContext.getApplicationContext() != null) {
                    _timer.cancel();

                    TransactionLegacy txn = TransactionLegacy.open(TransactionLegacy.CLOUD_DB);
                    try {
                        ComponentContext.initComponentsLifeCycle();
                    } finally {
                        txn.close();
                    }
                }
            }
        }, 0, 1000);
    }
}