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 * Licensed to the Apache Software Foundation (ASF) under one
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 * 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
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 * Unless required by applicable law or agreed to in writing,
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package com.sun.star.report;

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

/**
 * This allows the job processor to load data from a repository. It is assumed,
 * that all resource names are given as strings and furthermore, that the names
 * identify a resource uniquely within the input repository.
 *
 * An input repository connects the report processing to the xml definitions.
 * Unless defined otherwise, it is assumed, that the input-name is 'content.xml';
 * possible other files are 'settings.xml' and 'styles.xml' (see the Oasis standard
 * for details on these files and their contents).
 *
 * @author Thomas Morgner
 */
public interface InputRepository
{

    /**
     * Returns a unique identifier for this repository. Two repositories accessing
     * the same location should return the same id. The identifier must never
     * be null.
     *
     * @return the repository id
     */
    Object getId();

    InputStream createInputStream(final String name) throws IOException;

    /** allows to access sub repositories inside this repository
     * 
     * @param name describes the path to the sub repository
     * @return the sub repository
     * @throws java.io.IOException when the sub repository doesn't exist.
     */
    InputRepository openInputRepository(final String name) throws IOException;

    /**
     * This returns an version number for the given resource. Return zero, if
     * the resource is not versionable, else return a unique number for each version.
     * As rule of thumb: Increase the version number by at least one for each change
     * made to the resource.
     *
     * @param name the name of the resource
     * @return the version number
     */
    long getVersion(final String name);

    boolean exists(final String name);

    boolean isReadable(final String name);

    void closeInputRepository();

    /** returns the URL of the database document
     *
     * @return the URL of the database document
     */
    String getRootURL();
}