/*
* Licensed to the Apache Software Foundation (ASF) under one
* or more contributor license agreements. See the NOTICE file
* distributed with this work for additional information
* regarding copyright ownership. The ASF licenses this file
* to you 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.
*/
/**
* @fileoverview Support for basic logging capability for gadgets.
*
* This functionality replaces alert(msg) and window.console.log(msg).
*
* <p>Currently only works on browsers with a console (WebKit based browsers,
* Firefox with Firebug extension, or Opera).
*
* <p>API is designed to be equivalent to existing console.log | warn | error
* logging APIs supported by Firebug and WebKit based browsers. The only
* addition is the ability to call gadgets.setLogLevel().
*/
/**
* @static
* @namespace Support for basic logging capability for gadgets.
* @name gadgets.log
*/
gadgets.log = (function() {
/** @const */
var info_ = 1;
/** @const */
var warning_ = 2;
/** @const */
var error_ = 3;
/** @const */
var none_ = 4;
/**
* Log an informational message
* @param {Object} message - the message to log.
* @member gadgets
* @name log
* @function
*/
var log = function(message) {
logAtLevel(info_, message);
};
/**
* Log a warning
* @param {Object} message - the message to log.
* @static
*/
gadgets.warn = function(message) {
logAtLevel(warning_, message);
};
/**
* Log an error
* @param {Object} message - The message to log.
* @static
*/
gadgets.error = function(message) {
logAtLevel(error_, message);
};
/**
* Sets the log level threshold.
* @param {number} logLevel - New log level threshold.
* @static
* @member gadgets.log
* @name setLogLevel
*/
gadgets.setLogLevel = function(logLevel) {
logLevelThreshold_ = logLevel;
};
/**
* Logs a log message if output console is available, and log threshold is met.
* @param {number} level - the level to log with. Optional, defaults to gadgets.log.INFO.
* @param {Object} message - The message to log.
* @private
*/
function logAtLevel(level, message) {
if(typeof _console === 'undefined') {
//Purposely set to null if there is no console that way we don't come
//back in here
_console = window.console ? window.console :
window.opera ? window.opera.postError : null;
}
if (level < logLevelThreshold_ || !_console) {
return;
}
if (level === warning_ && _console.warn) {
_console.warn(message);
} else if (level === error_ && _console.error) {
_console.error(message);
} else if (_console.log) {
_console.log(message);
}
};
/**
* Log level for informational logging.
* @static
* @const
* @member gadgets.log
* @name INFO
*/
log['INFO'] = info_;
/**
* Log level for warning logging.
* @static
* @const
* @member gadgets.log
* @name WARNING
*/
log['WARNING'] = warning_;
/**
* Log level for no logging
* @static
* @const
* @member gadgets.log
* @name NONE
*/
log['NONE'] = none_;
/**
* Current log level threshold.
* @type {number}
* @private
*/
var logLevelThreshold_ = info_;
/**
* Console to log to
* @private
* @static
*/
var _console;
return log;
})();
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