Simple helper for print an url or an html

PrintHelper.java

/*
 * The MIT License (MIT)
 *
 * Copyright (c) 2016 Raphaël Bussa
 *
 * Permission is hereby granted, free of charge, to any person obtaining a copy
 * of this software and associated documentation files (the "Software"), to deal
 * in the Software without restriction, including without limitation the rights
 * to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
 * copies of the Software, and to permit persons to whom the Software is
 * furnished to do so, subject to the following conditions:
 *
 * The above copyright notice and this permission notice shall be included in all
 * copies or substantial portions of the Software.
 *
 * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
 * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
 * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
 * AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
 * LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
 * OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE
 * SOFTWARE.
 */

package rebus.utils.helper;

import android.annotation.TargetApi;
import android.content.Context;
import android.os.Build;
import android.print.PrintAttributes;
import android.print.PrintDocumentAdapter;
import android.print.PrintJob;
import android.print.PrintManager;
import android.text.Html;
import android.webkit.WebView;
import android.webkit.WebViewClient;

/**
 * Created by raphaelbussa on 02/05/16.
 */
public class PrintHelper {

    private Context context;
    private WebView webView;

    private String url;
    private String html;
    private String name;
    private CallBack callBack;

    /**
     * @param context current context
     */
    private PrintHelper(Context context) {
        this.context = context;
        this.webView = new WebView(context);
    }

    /**
     * @param context current context
     * @return new instance of PrintHelper
     */
    public static PrintHelper with(Context context) {
        return new PrintHelper(context);
    }

    /**
     * @param name document name
     * @return current instance
     */
    public PrintHelper name(String name) {
        this.name = Html.fromHtml(name).toString();
        return this;
    }

    /**
     * @param url url to print
     * @return current instance
     */
    public PrintHelper url(String url) {
        this.url = url;
        this.html = null;
        return this;
    }

    /**
     * @param html html to print
     * @return current instance
     */
    public PrintHelper html(String html) {
        this.html = html;
        this.url = null;
        return this;
    }

    /**
     * @param callBack interface with result of print
     */
    public void print(CallBack callBack) {
        this.callBack = callBack;
        if (url == null && html == null || name == null) {
            this.callBack.onFinish(RESULT.NULL_VALUES);
        } else {
            webView.setWebViewClient(new Client());
            if (url != null) {
                webView.loadUrl(url);
            }
            if (html != null) {
                webView.loadDataWithBaseURL(null, html, "text/HTML", "UTF-8", null);
            }
        }
    }

    /**
     * print method, checks that the Android version is superior to kitkat
     * create a PrintJob and add it to PrintManager
     * @throws Exception generic Exception, you never know
     */
    @TargetApi(Build.VERSION_CODES.KITKAT)
    private void printDocument() throws Exception {
        if (Build.VERSION.SDK_INT >= Build.VERSION_CODES.KITKAT) {
            PrintManager printManager = (PrintManager) context.getSystemService(Context.PRINT_SERVICE);
            PrintDocumentAdapter printAdapter;
            if (Build.VERSION.SDK_INT >= Build.VERSION_CODES.LOLLIPOP) {
                printAdapter = webView.createPrintDocumentAdapter(name);
            } else {
                printAdapter = webView.createPrintDocumentAdapter();
            }
            PrintJob printJob = printManager.print(name, printAdapter, new PrintAttributes.Builder().build());
            printManager.getPrintJobs().add(printJob);
            this.callBack.onFinish(RESULT.SUCCESS);
        } else {
            this.callBack.onFinish(RESULT.MIN_SDK);
        }
    }

    /**
     * Custom WebViewClient, in onPageFinished it call method printDocument()
     */
    private class Client extends WebViewClient {

        @Override
        public void onPageFinished(WebView view, String url) {
            super.onPageFinished(view, url);
            try {
                printDocument();
            } catch (Exception e) {
                callBack.onFinish(RESULT.ERROR);
            }
        }

    }


    /**
     * public enum of result type of print process
     */
    public enum RESULT {
        SUCCESS, MIN_SDK, ERROR, NULL_VALUES
    }

    /**
     * public interface with print process result
     */
    public interface CallBack {
        void onFinish(RESULT result);
    }

}