com.google.appinventor.client.output.OdeLog.java Source code

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Here is the source code for com.google.appinventor.client.output.OdeLog.java

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// -*- mode: java; c-basic-offset: 2; -*-
// Copyright 2009-2011 Google, All Rights reserved
// Copyright 2011-2012 MIT, All rights reserved
// Released under the Apache License, Version 2.0
// http://www.apache.org/licenses/LICENSE-2.0

package com.google.appinventor.client.output;

import com.google.appinventor.client.BugReport;
import com.google.appinventor.client.Ode;
import static com.google.appinventor.client.Ode.MESSAGES;
import com.google.appinventor.common.utils.StringUtils;
import com.google.appinventor.common.version.AppInventorFeatures;
import com.google.gwt.event.dom.client.ClickEvent;
import com.google.gwt.event.dom.client.ClickHandler;
import com.google.gwt.event.shared.UmbrellaException;
import com.google.gwt.user.client.ui.Button;
import com.google.gwt.user.client.ui.Composite;
import com.google.gwt.user.client.ui.HTML;
import com.google.gwt.user.client.ui.VerticalPanel;

import java.util.Set;

/**
 * Output panel for displaying ODE internal logging messages.
 *
 * <p>Note that logging is only active in hosted mode.
 *
 */
// TODO(user): Make this mesh with the new Logger interface.
public final class OdeLog extends Composite {

    // Singleton logging instance
    private static class SingletonHolder {
        private static final OdeLog INSTANCE = new OdeLog();
    }

    // Message style
    private static final String messageStyle = "style=\"font-size:small\"";

    // UI elements
    private final HTML text;

    /**
     * Returns singleton ODE logging instance.
     *
     * @return  ODE logging instance
     */
    public static OdeLog getOdeLog() {
        if (isLogAvailable()) {
            return SingletonHolder.INSTANCE;
        }

        throw new UnsupportedOperationException("logging not available");
    }

    /**
     * Creates a new output panel for displaying internal messages.
     */
    private OdeLog() {
        // Initialize UI
        Button clearButton = new Button(MESSAGES.clearButton());
        clearButton.addClickHandler(new ClickHandler() {
            @Override
            public void onClick(ClickEvent event) {
                clear();
            }
        });

        text = new HTML();
        text.setWidth("100%");

        VerticalPanel panel = new VerticalPanel();
        panel.add(clearButton);
        panel.add(text);
        panel.setSize("100%", "100%");
        panel.setCellHeight(text, "100%");
        panel.setCellWidth(text, "100%");

        initWidget(panel);
    }

    /**
     * Indicates whether logging is available.
     *
     * @return  logging availability
     */
    public static final boolean isLogAvailable() {
        return AppInventorFeatures.hasDebuggingView();
    }

    /**
     * Prints a log message.
     *
     * @param message  message to print
     */
    public static void log(String message) {
        if (isLogAvailable() && !Ode.isWindowClosing()) {
            getOdeLog().println(StringUtils.escape(message));
        }
    }

    /**
     * Prints a log warning message.
     *
     * @param message  message to print
     */
    public static void wlog(String message) {
        if (isLogAvailable() && !Ode.isWindowClosing()) {
            getOdeLog().wprintln(StringUtils.escape(message));
        }
    }

    /**
     * Prints a log error message.
     *
     * @param message  message to print
     */
    public static void elog(String message) {
        if (isLogAvailable() && !Ode.isWindowClosing()) {
            getOdeLog().eprintln(StringUtils.escape(message));
        }
    }

    /**
     * Prints a log message for an exception.
     *
     * @param throwable  exception thrown
     */
    public static void xlog(Throwable throwable) {
        if (isLogAvailable() && !Ode.isWindowClosing()) {
            getOdeLog().eprintln(StringUtils.escape(throwable.toString()) + prepareStackTrace(throwable));
            if (AppInventorFeatures.sendBugReports()) {
                // For this message, we don't escape. We want the bug report link to show as a link.
                getOdeLog().eprintln("File a <a href=\"" + BugReport.getBugReportLink(throwable)
                        + "\" target=\"_blank\">bug report</a> for this error.");
            }
        }
    }

    private static String prepareStackTrace(Throwable throwable) {
        StringBuilder html = new StringBuilder();
        html.append("<ul>");
        for (StackTraceElement element : throwable.getStackTrace()) {
            html.append("<li>").append(StringUtils.escape(element.toString())).append("</li>");
        }

        html.append(prepareCause(throwable.getCause()));

        if (throwable instanceof UmbrellaException) {
            Set<Throwable> causes = ((UmbrellaException) throwable).getCauses();
            if (causes != null && !causes.isEmpty()) {
                for (Throwable cause : causes) {
                    html.append(prepareCause(cause));
                }
            }
        }

        html.append("</ul>");
        return html.toString();
    }

    private static String prepareCause(Throwable cause) {
        StringBuilder html = new StringBuilder();
        if (cause != null) {
            html.append("<li>Caused by ").append(StringUtils.escape(cause.toString())).append("</li>")
                    .append(prepareStackTrace(cause));
        }
        return html.toString();
    }

    /*
     * Prints a log message.
     */
    private void println(String message) {
        text.setHTML(text.getHTML() + "<div " + messageStyle + ">" + "<span style=\"color:green\">[INFO] </span>"
                + message + "</div>");
    }

    /*
     * Prints a log warning message.
     */
    private void wprintln(String message) {
        text.setHTML(text.getHTML() + "<div " + messageStyle + ">"
                + "<span style=\"color:orange\">[WARNING] </span>" + message + "</div>");
    }

    /*
     * Prints a log error message.
     */
    private void eprintln(String message) {
        text.setHTML(text.getHTML() + "<div " + messageStyle + ">" + "<span style=\"color:red\">[ERROR] </span>"
                + message + "</div>");
    }

    /*
     * Clears all messages.
     */
    private void clear() {
        if (!Ode.isWindowClosing()) {
            text.setText("");
        }
    }
}