/*
 * 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.
 */

package org.apache.any23.http;

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

/**
 * Abstraction for opening an {@link InputStream} on an
 * HTTP IRI.
 *
 * @author Richard Cyganiak (richard@cyganiak.de)
 */
public interface HTTPClient {

    /**
     * Initializes the HTTP client.
     *
     * @param configuration configuration for the HTTP Client.
     */
    void init(HTTPClientConfiguration configuration);

    /**
     * Opens the input stream for the given target IRI.
     *
     * @param uri target IRI.
     * @return input stream to access IRI content.
     * @throws IOException if any error occurs while reading the IRI content.
     */
    InputStream openInputStream(String uri) throws IOException;

    /**
     * Release all static resources help by the instance. Call this
     * method only if you are sure you will not use it again in your
     * application, like for example when shutting down a servlet
     * context.
     */
    void close();

    /**
     * The value of the Content-Type header reported by the server.
     * Can be <code>null</code>.
     *
     * @return the content type as string.
     */
    String getContentType();

    /**
     * @return content length in bytes.
     */
    long getContentLength();

    /**
     * Returns the actual IRI from which the document was fetched.
     * This might differ from the IRI passed to openInputStream()
     * if a redirect was performed. A return value of <code>null</code>
     * means that the IRI is unchanged and the original IRI was used.
     *
     * @return actual document IRI.
     */
    String getActualDocumentIRI();
    
}