/**
* Copyright (C) 2011 Brian Ferris <bdferris@onebusaway.org>
*
* 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 org.onebusaway.container.rotation;
import java.io.IOException;
import java.io.Writer;
/**
* Defines a {@link Writer} rotation strategy that can be used in cooperation
* with {@link RotationWriter} to have one virtual {@link Writer} that seamless
* rotates output to multiple output writers.
*
* @author bdferris
* @see RotationWriter
* @see TimeRotationStrategy
*/
public interface RotationStrategy {
/**
* @return the Writer that will be used for initial output
* @throws IOException
*/
public Writer getFirstWriter() throws IOException;
/**
* Called to get the next output writer when a call is made to
* {@link RotationWriter#flush()}. The current writer is provided as a
* parameter, so if no rotation should occur, just return the current writer.
*
* @param writer the current output writer
* @param charactersWritten the number of characters written to the current
* writer
* @return the writer to output to in the future
* @throws IOException
*/
public Writer getNextWriter(Writer writer, int charactersWritten)
throws IOException;
}