se.kodapan.io.http.HttpGetReader.java Source code

Introduction

Here is the source code for se.kodapan.io.http.HttpGetReader.java

Source

/*
 * Copyright 2010 Kodapan
 *
 * 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 se.kodapan.io.http;

import org.apache.http.HttpResponse;
import org.apache.http.client.HttpClient;
import org.apache.http.client.methods.HttpGet;
import org.apache.http.impl.client.DefaultHttpClient;
import se.kodapan.io.GermanicInputStreamReader;

import java.io.IOException;
import java.io.InputStream;
import java.io.InputStreamReader;
import java.io.Reader;
import java.net.URI;
import java.net.URISyntaxException;
import java.util.regex.Matcher;
import java.util.regex.Pattern;

/**
 * @author kalle
 * @since 2010-apr-25 22:11:29
 */
public class HttpGetReader extends Reader {

    URI uri;
    HttpClient httpClient;

    public HttpGetReader(URI uri) {
        this(uri, new DefaultHttpClient());
    }

    public HttpGetReader(URI uri, HttpClient httpClient) {
        this.uri = uri;
        this.httpClient = httpClient;
    }

    public HttpGetReader(String uri) throws URISyntaxException {
        this(uri, new DefaultHttpClient());
    }

    public HttpGetReader(String uri, HttpClient httpClient) throws URISyntaxException {
        this.uri = new URI(uri);
        this.httpClient = httpClient;
    }

    private static final Pattern charsetPattern = Pattern.compile("^.+;\\s*charset\\s*=\\s*(.+)\\s*$",
            Pattern.CASE_INSENSITIVE);

    private Reader httpReader;

    @Override
    public int read(char[] chars, int i, int i1) throws IOException {

        if (httpReader == null) {

            HttpGet get = new HttpGet(uri);
            HttpClientUtil.addResponseHeaders(get);
            HttpResponse httpResponse = httpClient.execute(get);

            InputStream httpInputStream = httpResponse.getEntity().getContent();
            if (httpInputStream == null) {
                httpResponse.getEntity().consumeContent();
                throw new IOException(httpResponse.getStatusLine().toString());
            }

            String contentType = httpResponse.getEntity().getContentType() != null
                    ? httpResponse.getEntity().getContentType().getValue()
                    : null;
            String contentEncoding = httpResponse.getEntity().getContentEncoding() != null
                    ? httpResponse.getEntity().getContentEncoding().getValue()
                    : null;
            if (contentEncoding == null) {
                Matcher matcher = charsetPattern.matcher(contentType);
                if (matcher.matches()) {
                    contentEncoding = matcher.group(1);
                }
            }

            if (contentEncoding == null) {
                httpReader = new GermanicInputStreamReader(httpInputStream);
            } else {
                httpReader = new InputStreamReader(httpInputStream, contentEncoding);
            }

        }

        return httpReader.read(chars, i, i1);

    }

    @Override
    public void close() throws IOException {
        if (httpReader != null) {
            httpReader.close();
        }
        httpClient.getConnectionManager().shutdown();
    }
}