com.allen_sauer.gwt.log.client.WindowLogger.java Source code

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Here is the source code for com.allen_sauer.gwt.log.client.WindowLogger.java

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/*
 * Copyright 2009 Fred Sauer
 * 
 * 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.allen_sauer.gwt.log.client;

import com.google.gwt.core.client.JavaScriptException;
import com.google.gwt.core.client.JavaScriptObject;
import com.google.gwt.event.logical.shared.CloseEvent;
import com.google.gwt.event.logical.shared.CloseHandler;
import com.google.gwt.user.client.Timer;
import com.google.gwt.user.client.Window;

import com.allen_sauer.gwt.log.client.impl.LogClientBundle;
import com.allen_sauer.gwt.log.client.util.DOMUtil;
import com.allen_sauer.gwt.log.shared.LogRecord;

/**
 * Logger which outputs to a draggable floating <code>DIV</code>.
 * 
 * TODO Fix lack of updates when Firefox is configured to force new windows to open as tabs
 */
public class WindowLogger implements Logger {
    // CHECKSTYLE_JAVADOC_OFF

    private static final String STACKTRACE_ELEMENT_PREFIX = "&nbsp;&nbsp;&nbsp;&nbsp;at&nbsp;";

    private String logText = "";
    private boolean ready = false;
    private JavaScriptObject window = null;

    private final CloseHandler<Window> windowCloseListener = new CloseHandler<Window>() {
        @Override
        public void onClose(CloseEvent<Window> event) {
            closeWindowIfOpen();
        }
    };

    /**
     * Default constructor.
     */
    public WindowLogger() {
        Window.addCloseHandler(windowCloseListener);
    }

    @Override
    public final void clear() {
        if (ready) {
            try {
                DOMUtil.windowClear(window);
            } catch (RuntimeException e) {
                // ignore
            }
        }
    }

    @Override
    public final boolean isSupported() {
        return true;
    }

    @Override
    public void log(LogRecord record) {
        String message = record.getFormattedMessage();
        Throwable throwable = record.getThrowable();
        String text = message.replaceAll("<", "&lt;").replaceAll(">", "&gt;");
        String title = makeTitle(message, throwable);
        if (throwable != null) {
            text += "\n";
            while (throwable != null) {
                /* Use throwable.toString() and not throwable.getClass().getName() and
                 * throwable.getMessage(), so that instances of UnwrappedClientThrowable, when stack trace
                 * deobfuscation is enabled) display properly
                 */
                text += "<b>" + throwable.toString() + "</b>";
                StackTraceElement[] stackTraceElements = throwable.getStackTrace();
                if (stackTraceElements.length > 0) {
                    text += "<div class='log-stacktrace'>";
                    for (StackTraceElement element : stackTraceElements) {
                        text += STACKTRACE_ELEMENT_PREFIX + element + "<br>";
                    }
                    text += "</div>";
                }
                throwable = throwable.getCause();
                if (throwable != null) {
                    text += "Caused by: ";
                }
            }
        }
        text = text.replaceAll("\r\n|\r|\n", "<BR>");
        addLogText("<div class='" + LogClientBundle.INSTANCE.css().logMessage()
                + "' onmouseover='className+=\" log-message-hover\"' "
                + "onmouseout='className=className.replace(/ log-message-hover/g,\"\")' style='color: "
                + getColor(record.getLevel()) + "' title='" + title + "'>" + text + "</div>");
    }

    @Override
    public void setCurrentLogLevel(int level) {
        // do no
    }

    private void addLogText(String text) {
        logText += text;
        if (window == null) {
            openNewWindow();
        }
        logPendingText();
    }

    private void closeWindowIfOpen() {
        if (window != null) {
            ready = false;
            DOMUtil.windowClose(window);
            window = null;
        }
    }

    private String getColor(int logLevel) {
        if (logLevel == Log.LOG_LEVEL_OFF) {
            return "#000"; // black
        }
        if (logLevel >= Log.LOG_LEVEL_FATAL) {
            return "#F00"; // bright red
        }
        if (logLevel >= Log.LOG_LEVEL_ERROR) {
            return "#C11B17"; // dark red
        }
        if (logLevel >= Log.LOG_LEVEL_WARN) {
            return "#E56717"; // dark orange
        }
        if (logLevel >= Log.LOG_LEVEL_INFO) {
            return "#2B60DE"; // blue
        }
        return "#20b000"; // green
    }

    private void logPendingText() {
        if (ready) {
            try {
                DOMUtil.windowWrapAndAppendHTML(window, logText);
                logText = "";
            } catch (JavaScriptException e) {
                openNewWindow();
            }
        }
    }

    private String makeTitle(String message, Throwable throwable) {
        if (throwable != null) {
            if (throwable.getMessage() == null) {
                message = throwable.getClass().getName();
            } else {
                message = throwable.getMessage()
                        .replaceAll(throwable.getClass().getName().replaceAll("^(.+\\.).+$", "$1"), "");
            }
        }
        return DOMUtil.adjustTitleLineBreaks(message).replaceAll("<", "&lt;").replaceAll(">", "&gt;")
                .replaceAll("'", "\"");
    }

    private void openNewWindow() {
        closeWindowIfOpen();
        window = DOMUtil.windowOpen("");
        new Timer() {
            int counter = 0;

            @Override
            public void run() {
                try {
                    if (counter++ > 100 || "complete".equals(DOMUtil.windowReadyState(window))) {
                        DOMUtil.windowSetTitle(window, "[log] " + Window.getTitle());
                        ready = true;
                        cancel();
                        logPendingText();
                    }
                } catch (RuntimeException e) {
                    window = null;
                    cancel();
                }
            }
        }.scheduleRepeating(100);
    }
}