//
// Copyright (c) 2004,2005 Jaroslaw Kowalski <jkowalski@users.sourceforge.net>
//
//
// All rights reserved.
//
// Redistribution and use in source and binary forms, with or without
// modification, are permitted provided that the following conditions
// are met:
//
// * Redistributions of source code must retain the above copyright notice,
// this list of conditions and the following disclaimer.
//
// * Redistributions in binary form must reproduce the above copyright notice,
// this list of conditions and the following disclaimer in the documentation
// and/or other materials provided with the distribution.
//
// * Neither the name of the Jaroslaw Kowalski nor the names of its
// contributors may be used to endorse or promote products derived from this
// software without specific prior written permission.
//
// THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS IS"
// AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
// IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
// ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT OWNER OR CONTRIBUTORS BE
// LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR
// CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF
// SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS
// INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN
// CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE)
// ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF
// THE POSSIBILITY OF SUCH DAMAGE.
//
using System;
using System.Text;
using System.Collections;
using System.Globalization;
namespace NLog.LayoutRenderers
{
/// <summary>
/// A counter value (increases on each layout rendering).
/// </summary>
[LayoutRenderer("counter")]
public class CounterLayoutRenderer: LayoutRenderer
{
private int _value = 1;
private string _sequence = null;
private int _increment = 1;
/// <summary>
/// The initial value of the counter
/// </summary>
[System.ComponentModel.DefaultValue(1)]
public int Value
{
get
{
return _value;
}
set
{
_value = value;
}
}
/// <summary>
/// The value to be added to the counter after each layout rendering.
/// </summary>
[System.ComponentModel.DefaultValue(1)]
public int Increment
{
get
{
return _increment;
}
set
{
_increment = value;
}
}
/// <summary>
/// The name of the sequence. Different named sequences can have individual values.
/// </summary>
public string Sequence
{
get
{
return _sequence;
}
set
{
_sequence = value;
}
}
/// <summary>
/// Returns the estimated number of characters that are needed to
/// hold the rendered value for the specified logging event.
/// </summary>
/// <param name="ev">Logging event information.</param>
/// <returns>The number of characters.</returns>
/// <remarks>
/// If the exact number is not known or
/// expensive to calculate this function should return a rough estimate
/// that's big enough in most cases, but not too big, in order to conserve memory.
/// </remarks>
protected internal override int GetEstimatedBufferSize(LogEventInfo ev)
{
return 32;
}
/// <summary>
/// Renders the specified counter value and appends it to the specified <see cref="StringBuilder" />.
/// </summary>
/// <param name="builder">The <see cref="StringBuilder"/> to append the rendered data to.</param>
/// <param name="ev">Logging event.</param>
protected internal override void Append(StringBuilder builder, LogEventInfo ev)
{
int v;
if (_sequence != null)
{
v = GetNextSequenceValue(Sequence, Value, Increment);
}
else
{
v = _value;
_value += _increment;
}
builder.Append(ApplyPadding(v.ToString(Culture)));
}
private static Hashtable _sequences = new Hashtable();
private static int GetNextSequenceValue(string sequenceName, int defaultValue, int increment)
{
lock(_sequences)
{
object v = _sequences[sequenceName];
int val;
if (v == null)
{
val = defaultValue;
}
else
{
val = (int)v;
}
int retVal = val;
val += increment;
_sequences[sequenceName] = val;
return retVal;
}
}
}
}