com.google.gwt.gen2.logging.shared.LogFormatter.java Source code

Introduction

Here is the source code for com.google.gwt.gen2.logging.shared.LogFormatter.java

Source

/*
 * Copyright 2008 Google Inc.
 * 
 * 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.google.gwt.gen2.logging.shared;

/**
 * Formatter used to format logging messages.
 */
public abstract class LogFormatter {
    /**
     * Default text log formatter.
     */
    public static LogFormatter TEXT = new LogFormatter() {
        @Override
        public String format(LogEvent event) {
            StringBuffer accum = new StringBuffer(event.getLevel().getName());
            if (event.getCategory() != null) {
                accum.append("-" + event.getCategory());
            }
            accum.append("-" + event.getTime());
            accum.append("\n" + event.getMessage());
            if (event.getThrown() != null) {
                accum.append("\n thrown: " + event.getThrown());
            }
            return accum.toString();
        }

        @Override
        public boolean isHtml() {
            return false;
        }
    };

    /**
     * Default html log formatter.
     */
    public static LogFormatter HTML = new LogFormatter() {
        @Override
        public String format(LogEvent event) {
            String baseMessage = escapeText(event.getMessage());
            String title = "level: " + event.getLevel();
            String category = event.getCategory();
            if (category != null) {
                title += "  category: " + event.getCategory();
            }
            title += "  time: " + event.getTime();
            if (event.getThrown() != null) {
                title += "  thrown: " + event.getThrown();
            }

            String style = getStyle(event.getLevel());
            String htmlMessage = "<code class='" + style + "'" + "title='" + title + "'>" + baseMessage + "</code>";
            return htmlMessage;
        }

        @Override
        public boolean isHtml() {
            return true;
        }

    };

    /**
     * Escapes the given text so it can be displayed as html.
     * 
     * @param text the text to escape
     * @return the escaped text
     */
    // TODO(ecc) check for other chars to escape.
    public static String escapeText(String text) {
        text = text.replaceAll("<", "&lt;");
        text = text.replaceAll(">", "&gt;");
        return text;
    }

    /**
     * Gets the style name associated with all predefined levels. This interface
     * is primarily used by widget log handlers to display log levels
     * consistently.
     * 
     * In other words, uses "log" + name of level to calculate the level name.
     * 
     * @param level level
     * 
     * @return style name
     */
    public static String getStyle(Level level) {
        return "log" + level.getName();
    }

    /**
     * Formats the given log event.
     * 
     * @param event the event
     * @return the formatted string
     */
    public abstract String format(LogEvent event);

    /**
     * Is the resulting formatted string in html format?
     * 
     * @return is html
     */
    public abstract boolean isHtml();
}