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Commons Yapbam classes used by desktop and Android versions.

There is a newer version: 1.9.1

package net.yapbam.remote;

import java.io.IOException;
import java.io.InputStream;
import java.io.OutputStream;

/** A Cache.
 * 
This converter use cache in order to preserve web server resources, and to be able to work with no Internet connection.
 * 
To improve the cache robustness, the cache may have two levels:
 * A temporary cache that is used to store the data read from Internet.
 * A persistent cache that saved the temporary one after it was validated by a successful parsing (see {@link #commit()}).
 * @author Jean-Marc Astesana
 */
public interface Cache {
	/** Tests whether the cache is empty or not.
	 * 
The cache is empty if both temporary and saved cache are not available.
	 * @return true if the cache is empty.
	 */
	public boolean isEmpty();
	
	/** Gets an output stream to the temporary cache.
	 * @return An output stream.
	 * @throws IOException if an error occurs while creating the writer. 
	 */
	public OutputStream getOutputStream() throws IOException;
	
	/** Gets an input stream to the cache.
	 * @param tmp true if the temporary cache is required
	 * @return An input stream.
	 * @throws IOException if an error occurs while creating the reader. 
	 */
	public InputStream getInputStream(boolean tmp) throws IOException;
	
	/** Commits the temporary cache.
	 * 
This method is called once temporary cache has been successfully parsed.
	 * @throws IOException if the commit fails
	 */
	public void commit() throws IOException;
	
	/** Gets Gives when the cache persist has been updated (ms since 1/1/1970).
	 * @return a long (-1 is no persistent cache is available)
	 */
	public long getTimeStamp();
}