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# Code for HTTP Example

    /****************************************************************************
    **
    ** Copyright (C) 1992-2008 Trolltech ASA. All rights reserved.
    **
    ** This file is part of Qt Jambi.
    **
    ** ** This file may be used under the terms of the GNU General Public
    ** License version 2.0 as published by the Free Software Foundation
    ** and appearing in the file LICENSE.GPL included in the packaging of
    ** this file.  Please review the following information to ensure GNU
    ** General Public Licensing requirements will be met:
    ** http://www.trolltech.com/products/qt/opensource.html
    **
    ** If you are unsure which license is appropriate for your use, please
    ** review the following information:
    ** http://www.trolltech.com/products/qt/licensing.html or contact the
    ** sales department at sales@trolltech.com.

    **
    ** This file is provided AS IS with NO WARRANTY OF ANY KIND, INCLUDING THE
    ** WARRANTY OF DESIGN, MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE.
    **
    ****************************************************************************/

    package com.trolltech.examples;

    import com.trolltech.qt.core.*;
    import com.trolltech.qt.gui.*;
    import com.trolltech.qt.network.*;

    @QtJambiExample(name = "Http Example")
    public class Http extends QDialog
    {
        private QLabel statusLabel;
        private QLabel urlLabel;
        private QLineEdit urlLineEdit;
        private QProgressDialog progressDialog;
        private QPushButton downloadButton;
        private QPushButton quitButton;
        private QDialogButtonBox buttonBox;

        private QHttp http;
        private QFile file;
        private int httpGetId;
        private boolean httpRequestAborted;

        public Http()
        {
            urlLineEdit = new QLineEdit("https://");

            urlLabel = new QLabel(tr("&URL:"));
            urlLabel.setBuddy(urlLineEdit);
            statusLabel = new QLabel(tr("Please enter the URL of a file you want "
                                        + " to download."));

            downloadButton = new QPushButton(tr("Download"));
            downloadButton.setDefault(true);
            quitButton = new QPushButton(tr("Quit"));
            quitButton.setAutoDefault(false);

            buttonBox = new QDialogButtonBox();
            buttonBox.addButton(downloadButton, QDialogButtonBox.ButtonRole.ActionRole);
            buttonBox.addButton(quitButton, QDialogButtonBox.ButtonRole.RejectRole);

            progressDialog = new QProgressDialog(this);

            http = new QHttp(this);

            urlLineEdit.textChanged.connect(this, "enableDownloadButton()");
            http.requestFinished.connect(this, "httpRequestFinished(int, boolean)");
            http.dataReadProgress.connect(this, "updateDataReadProgress(int,int)");
            http.responseHeaderReceived.connect(this,
                "readResponseHeader(QHttpResponseHeader)");
            http.authenticationRequired.connect(this,
                "slotAuthenticationRequired(String,int,QAuthenticator)");
            progressDialog.canceled.connect(this, "cancelDownload()");
            downloadButton.clicked.connect(this, "downloadFile()");
            quitButton.clicked.connect(this, "close()");

            QHBoxLayout topLayout = new QHBoxLayout();
            topLayout.addWidget(urlLabel);
            topLayout.addWidget(urlLineEdit);

            QVBoxLayout mainLayout = new QVBoxLayout();
            mainLayout.addLayout(topLayout);
            mainLayout.addWidget(statusLabel);
            mainLayout.addWidget(buttonBox);
            setLayout(mainLayout);

            setWindowTitle(tr("HTTP"));
            urlLineEdit.setFocus();
        }

        private void downloadFile()
        {
            String text = urlLineEdit.text();

            QUrl url = new QUrl(text);
            if (text.endsWith(url.host()))
                url = new QUrl(text + "/");

            QFileInfo fileInfo = new QFileInfo(url.path());
            String fileName = fileInfo.fileName();
            if (fileName.equals(""))
                fileName = "index.html";

            if (QFile.exists(fileName)) {
                QMessageBox.StandardButtons buttons = QMessageBox.StandardButton.createQFlags(
                    QMessageBox.StandardButton.Ok, QMessageBox.StandardButton.Cancel);

                if (QMessageBox.question(this, tr("HTTP"), tr("There already exists a file called ")
                    + fileName + tr(" the current directory. Overwrite?"), buttons,
                    QMessageBox.StandardButton.Cancel).equals(QMessageBox.StandardButton.Cancel))
                    return;

                QFile.remove(fileName);
            }

            file = new QFile(fileName);
            if (!file.open(QIODevice.OpenModeFlag.WriteOnly)) {
                QMessageBox.information(this, tr("HTTP"), tr("Unable to save the file ")
                                        + fileName + tr(":") + file.errorString());
                file = null;
                return;
            }

            QHttp.ConnectionMode mode = url.scheme().toLowerCase().equals("https")
                                        ? QHttp.ConnectionMode.ConnectionModeHttps
                                        : QHttp.ConnectionMode.ConnectionModeHttp;
            http.setHost(url.host(), mode, url.port() == -1 ? 0 : url.port());

            if (!url.userName().equals(""))
                http.setUser(url.userName(), url.password());

            httpRequestAborted = false;
            httpGetId = http.get(url.path(), file);

            progressDialog.show();
            progressDialog.setWindowTitle(tr("HTTP"));
            progressDialog.setLabelText(tr("Downloading: ") + fileName + tr("."));
            downloadButton.setEnabled(false);
        }

        private void cancelDownload()
        {
            statusLabel.setText(tr("Download canceled."));
            httpRequestAborted = true;
            http.abort();
            downloadButton.setEnabled(true);
        }

        private void httpRequestFinished(int requestId, boolean error)
        {
            if (requestId != httpGetId)
                return;
            if (httpRequestAborted) {
                if (file != null) {
                    file.close();
                    file.remove();
                    file = null;
                }

                progressDialog.hide();
                return;
            }

            if (requestId != httpGetId)
                return;

            progressDialog.hide();
            file.close();

            if (error) {
                file.remove();
                QMessageBox.information(this, tr("HTTP"),
                                         tr("Download failed ") +
                                         http.errorString() + tr("."));
            } else {
                String fileName = new QFileInfo(new QUrl(urlLineEdit.text()).path()).fileName();
                statusLabel.setText(tr("Downloaded: \"") + fileName + tr("\" to current directory."));
            }

            downloadButton.setEnabled(true);
            file = null;
        }

        private void readResponseHeader(QHttpResponseHeader responseHeader)
        {
            if (responseHeader.statusCode() != 200) {
                QMessageBox.information(this, tr("HTTP"),
                                         tr("Download failed: ")
                                         +responseHeader.reasonPhrase() + tr("."));
                httpRequestAborted = true;
                progressDialog.hide();
                http.abort();
            }
        }

        private void updateDataReadProgress(int bytesRead, int totalBytes)
        {
            if (httpRequestAborted)
                return;

            progressDialog.setMaximum(totalBytes);
            progressDialog.setValue(bytesRead);
        }

        private void enableDownloadButton()
        {
            downloadButton.setEnabled(!urlLineEdit.text().equals(""));
        }

        private void slotAuthenticationRequired(String hostName, int i, QAuthenticator authenticator)
        {
            QDialog dlg = new QDialog();
            Ui_Dialog ui = null;
            ui.setupUi(dlg);
            dlg.adjustSize();
            ui.siteDescription.setText(authenticator.realm() + tr(" at ") + hostName);

            if (dlg.exec() == QDialog.DialogCode.Accepted.value()) {
                authenticator.setUser(ui.userEdit.text());
                authenticator.setPassword(ui.passwordEdit.text());
            }
        }

        public static void main(String args[])
        {
            QApplication.initialize(args);

            Http window = new Http();
            window.show();

            QApplication.exec();
        }

    }