001/**
002 *
003 * Copyright © 2014-2021 Florian Schmaus
004 *
005 * Licensed under the Apache License, Version 2.0 (the "License");
006 * you may not use this file except in compliance with the License.
007 * You may obtain a copy of the License at
008 *
009 *     http://www.apache.org/licenses/LICENSE-2.0
010 *
011 * Unless required by applicable law or agreed to in writing, software
012 * distributed under the License is distributed on an "AS IS" BASIS,
013 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
014 * See the License for the specific language governing permissions and
015 * limitations under the License.
016 */
017
018package org.jivesoftware.smack.provider;
019
020import java.io.IOException;
021import java.text.ParseException;
022
023import org.jivesoftware.smack.packet.Element;
024import org.jivesoftware.smack.packet.XmlEnvironment;
025import org.jivesoftware.smack.parsing.SmackParsingException;
026import org.jivesoftware.smack.util.ParserUtils;
027import org.jivesoftware.smack.xml.XmlPullParser;
028import org.jivesoftware.smack.xml.XmlPullParserException;
029
030/**
031 * Smack provider are the parsers used to deserialize raw XMPP into the according Java {@link Element}s.
032 * <p>
033 * At any time when {@link #parse(XmlPullParser, int, XmlEnvironment)} is invoked any type of exception can be thrown. If the parsed
034 * element does not follow the specification, for example by putting a string where only integers are allowed, then a
035 * {@link org.jivesoftware.smack.SmackException} should be thrown.
036 * </p>
037 *
038 * @author Florian Schmaus
039 * @param <E> the type of the resulting element.
040 */
041public abstract class Provider<E extends Element> extends AbstractProvider<E> {
042
043    public final E parse(XmlPullParser parser) throws IOException, XmlPullParserException, SmackParsingException {
044        return parse(parser, null);
045    }
046
047    public final E parse(XmlPullParser parser, XmlEnvironment outerXmlEnvironment) throws IOException, XmlPullParserException, SmackParsingException {
048        // XPP3 calling convention assert: Parser should be at start tag
049        ParserUtils.assertAtStartTag(parser);
050
051        final int initialDepth = parser.getDepth();
052        final XmlEnvironment xmlEnvironment = XmlEnvironment.from(parser, outerXmlEnvironment);
053
054        E e = wrapExceptions(() -> parse(parser, initialDepth, xmlEnvironment));
055
056        // XPP3 calling convention assert: Parser should be at end tag of the consumed/parsed element
057        ParserUtils.forwardToEndTagOfDepth(parser, initialDepth);
058        return e;
059    }
060
061    public abstract E parse(XmlPullParser parser, int initialDepth, XmlEnvironment xmlEnvironment)
062                    throws XmlPullParserException, IOException, SmackParsingException, ParseException;
063}