BaseConnection.java

package com.epam.cisen.core.connector;

import java.io.IOException;
import java.io.InputStream;
import java.net.URL;
import java.net.URLConnection;
import java.util.Scanner;

import org.apache.commons.codec.binary.Base64;
import org.apache.commons.lang.StringUtils;

public class BaseConnection {

    private String baseAddress;
    private String token;

    public BaseConnection(String baseAddress) {
        this(baseAddress, null, null);
    }

    public BaseConnection(String baseAddress, String login, String pass) {
        if (baseAddress == null) {
            throw new IllegalArgumentException("Address cannot be null.");
        }
        this.baseAddress = baseAddress.endsWith("/") ? baseAddress.substring(0, baseAddress.length() - 1) : baseAddress;
        this.token = toToken(login, pass);
    }

    private String toToken(String login, String pass) {
        if (StringUtils.isBlank(login) || StringUtils.isBlank(pass)) {
            return null;
        }
        String authStr = login + ":" + pass;
        byte[] authArray = Base64.encodeBase64(authStr.getBytes());
        return new String(authArray);
    }

    public String read(String subAddress, Object... params) throws IOException {
        String urlStr = baseAddress + String.format(subAddress, params);
        URL url = new URL(urlStr);
        URLConnection connection = url.openConnection();
        if (token != null) {
            connection.setRequestProperty("Authorization", "Basic " + token);
        }
        return read(connection.getInputStream());
    }

    private String read(InputStream is) throws IOException {
        StringBuilder result = new StringBuilder();

        try (Scanner scanner = new Scanner(is)) {
            while (scanner.hasNextLine()) {
                result.append(scanner.nextLine());
            }
        }
        return result.toString();
    }

}