com.netbout.client.RtMessageIterator Maven / Gradle / Ivy
/**
* Copyright (c) 2009-2016, netbout.com
* All rights reserved.
*
* Redistribution and use in source and binary forms, with or without
* modification, are PROHIBITED without prior written permission from
* the author. This product may NOT be used anywhere and on any computer
* except the server platform of netbout Inc. located at www.netbout.com.
* Federal copyright law prohibits unauthorized reproduction by any means
* and imposes fines up to $25,000 for violation. If you received
* this code accidentally and without intent to use it, please report this
* incident to the author by email.
*
* THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
* "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
* LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
* A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
* OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
* SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
* LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
* DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON
* ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY,
* OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT
* OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
* SUCH DAMAGE.
*/
package com.netbout.client;
import com.google.common.base.Function;
import com.google.common.collect.Lists;
import com.jcabi.aspects.Loggable;
import com.jcabi.http.Request;
import com.jcabi.http.response.RestResponse;
import com.jcabi.http.response.XmlResponse;
import com.jcabi.xml.XML;
import com.netbout.spi.Message;
import java.io.IOException;
import java.net.HttpURLConnection;
import java.text.ParseException;
import java.util.Date;
import java.util.Iterator;
import java.util.LinkedList;
import java.util.NoSuchElementException;
import java.util.Queue;
import lombok.EqualsAndHashCode;
import lombok.ToString;
import org.apache.commons.lang3.time.DateFormatUtils;
/**
* REST bout iterator.
*
* @author Yegor Bugayenko ([email protected])
* @version $Id: 6fecab227e972833c507b3309853688c924bbb60 $
* @since 2.14
*/
@ToString
@Loggable(Loggable.DEBUG)
@EqualsAndHashCode(of = { "request", "messages" })
final class RtMessageIterator implements Iterator {
/**
* Pre-fetched messages.
*/
private final transient Queue messages = new LinkedList();
/**
* Request to use.
*/
private transient Request request;
/**
* Has more?
*/
private transient boolean more = true;
/**
* Public ctor.
* @param req Request to use
*/
RtMessageIterator(final Request req) {
this.request = req;
}
@Override
public boolean hasNext() {
if (this.messages.isEmpty() && this.more) {
try {
this.fetch();
} catch (final IOException ex) {
throw new IllegalStateException(ex);
}
}
return !this.messages.isEmpty();
}
@Override
public Message next() {
if (!this.hasNext()) {
throw new NoSuchElementException("end of the bout");
}
return this.messages.poll();
}
@Override
public void remove() {
throw new UnsupportedOperationException("#remove()");
}
/**
* Fetch more.
* @throws IOException If fails
*/
private void fetch() throws IOException {
final XmlResponse response = this.request.fetch()
.as(RestResponse.class)
.assertStatus(HttpURLConnection.HTTP_OK)
.as(XmlResponse.class);
final XML xml = response.xml();
this.messages.addAll(
Lists.transform(
xml.nodes("/page/bout/messages/message"),
new Function() {
@Override
public Message apply(final XML node) {
return RtMessageIterator.msg(node);
}
}
)
);
if (xml.nodes("/page/bout/messages/message ").isEmpty()) {
this.more = false;
} else {
this.request = response.rel(
// @checkstyle LineLength (1 line)
"/page/bout/messages/message[last()]/links/link[@rel='more']/@href"
);
}
}
/**
* Turn XML into a message.
* @param xml The XML
* @return Message
*/
private static Message msg(final XML xml) {
// @checkstyle AnonInnerLengthCheck (50 lines)
return new Message() {
@Override
public long number() {
return Long.parseLong(
xml.xpath("number/text()").get(0)
);
}
@Override
public Date date() throws IOException {
try {
return DateFormatUtils.ISO_DATETIME_FORMAT.parse(
xml.xpath("date/text()").get(0)
);
} catch (final ParseException ex) {
throw new IOException(ex);
}
}
@Override
public String text() {
return xml.xpath("text/text()").get(0);
}
@Override
public String author() {
return xml.xpath("author/text()").get(0);
}
};
}
}