com.github.arnabk.BlockingChecker.java Source code

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Here is the source code for com.github.arnabk.BlockingChecker.java

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/*
 * Copyright 2014 arnab.
 *
 * Licensed 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.github.arnabk;

import java.util.Date;
import java.util.logging.Level;
import java.util.logging.Logger;
import org.apache.commons.lang3.StringUtils;
import org.apache.http.client.fluent.Request;

/**
 * This is a blocking call and the caller will be waiting forever after this call. This class will continuously check the hostsToCheck status after
 * frequencyInMins interval has elapsed
 * 
 * This class will also prepend http if it has not been already added to the website URL
 * 
 * @author arnab
 */
public class BlockingChecker {

    public void execute(int frequencyInMins, String... hostsToCheck) {

        while (true) {

            for (int index = 1; index < hostsToCheck.length; index++) {
                StringBuilder sb = new StringBuilder();
                sb.append("Timestamp : ").append(new Date()).append(", ").append("Server : ")
                        .append(hostsToCheck[index]).append(", ").append("Status code : ");
                try {
                    sb.append(Request.Head(prepareURL(StringUtils.trimToEmpty(hostsToCheck[index]))).execute()
                            .returnResponse().getStatusLine().getStatusCode());
                } catch (Exception e) {
                    sb.append(" Request failed!");
                }
                System.out.println(sb);
            }

            try {
                synchronized (this) {
                    wait(frequencyInMins * 60 * 1000);
                }
            } catch (InterruptedException ex) {
                Logger.getLogger(App.class.getName()).log(Level.SEVERE, null, ex);
            }

        }

    }

    private String prepareURL(String url) {
        if (url.startsWith("http")) {
            return url;
        } else {
            return "http://" + url;
        }
    }

}