org.dizitart.no2.Document Maven / Gradle / Ivy
/*
*
* Copyright 2017-2018 Nitrite author or authors.
*
* 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 org.dizitart.no2;
import org.dizitart.no2.exceptions.InvalidIdException;
import org.dizitart.no2.exceptions.InvalidOperationException;
import org.dizitart.no2.exceptions.ValidationException;
import java.io.Serializable;
import java.util.Iterator;
import java.util.LinkedHashMap;
import java.util.Map;
import static org.dizitart.no2.Constants.*;
import static org.dizitart.no2.NitriteId.createId;
import static org.dizitart.no2.NitriteId.newId;
import static org.dizitart.no2.exceptions.ErrorCodes.*;
import static org.dizitart.no2.exceptions.ErrorMessage.DOC_GET_TYPE_NULL;
import static org.dizitart.no2.exceptions.ErrorMessage.errorMessage;
import static org.dizitart.no2.util.ValidationUtils.notNull;
/**
* Represents a type-safe container of nitrite document. It is a collection
* of key-value pairs.
*
* [[app-listing]]
* [source,java]
* .Example
* --
* include::/src/docs/asciidoc/examples/document.adoc[]
* --
*
* @author Anindya Chatterjee.
* @since 1.0
*/
public class Document extends LinkedHashMap implements Iterable {
private static final long serialVersionUID = 1477462374L;
/**
* Instantiates an empty document.
*/
public Document() {
}
/**
* Instantiates a new Document from a map.
*
* @param map the map
*/
public Document(Map map) {
super(map);
}
/**
* Instantiates a new {@link Document} from a key-value pair.
*
* @param key the key
* @param value the value
* @return the document
*/
public static Document createDocument(final String key, final Object value) {
Document document = new Document();
document.put(key, value);
return document;
}
/**
* Append document with new key and value pair.
*
* @param key the key
* @param value the value
* @return the document
*/
@Override
public Document put(final String key, final Object value) {
if (DOC_ID.contentEquals(key) && !validId(value)) {
throw new InvalidOperationException(
errorMessage("document id is an auto generated value and can not be " + value,
IOE_DOC_ID_AUTO_GENERATED));
}
if (value != null && !Serializable.class.isAssignableFrom(value.getClass())) {
throw new ValidationException(
errorMessage("type " + value.getClass().getName() + " does not implement java.io.Serializable",
VE_TYPE_NOT_SERIALIZABLE));
}
super.put(key, value);
return this;
}
/**
* Get object specified with the `key`.
*
* @param key the key
* @return the object
*/
public Object get(String key) {
return super.get(key);
}
/**
* Get object of type `T`.
*
* @param the type parameter
* @param key the key
* @param type the type
* @return the object of type `T`.
*/
public T get(String key, Class type) {
notNull(type, DOC_GET_TYPE_NULL);
return type.cast(super.get(key));
}
/**
* Gets the _id field of the document. If it
* does not exists, it will create and save one.
*
* @return the _id field of the document.
* @see NitriteId
*/
@SuppressWarnings("unchecked")
public NitriteId getId() {
Long id = null;
try {
if (!containsKey(DOC_ID)) {
id = newId().getIdValue();
super.put(DOC_ID, id);
} else {
id = (Long) get(DOC_ID);
}
return createId(id);
} catch (ClassCastException cce) {
throw new InvalidIdException(errorMessage("invalid _id found " + id,
IIE_INVALID_ID_FOUND));
}
}
/**
* Gets the document revision number.
*
* @return the revision number.
*/
public int getRevision() {
if (!containsKey(DOC_REVISION)) {
return 0;
}
return get(DOC_REVISION, Integer.class);
}
/**
* Gets the source of the documents. For Nitrite replicator,
* the value for this field will be {@link Constants#REPLICATOR}.
*
* @return the source of the documents.
*/
public String getSource() {
if (!containsKey(DOC_SOURCE)) {
return "";
}
return get(DOC_SOURCE, String.class);
}
/**
* Gets the last modified time of the documents.
*
* @return the last modified time of the documents.
*/
public long getLastModifiedTime() {
if (!containsKey(DOC_MODIFIED)) {
return 0;
}
return get(DOC_MODIFIED, Long.class);
}
@Override
public Iterator iterator() {
return new PairIterator(super.entrySet().iterator());
}
private class PairIterator implements Iterator {
private Iterator> iterator;
PairIterator(Iterator> iterator) {
this.iterator = iterator;
}
@Override
public boolean hasNext() {
return iterator.hasNext();
}
@Override
public KeyValuePair next() {
Map.Entry next = iterator.next();
return new KeyValuePair(next.getKey(), next.getValue());
}
@Override
public void remove() {
iterator.remove();
}
}
private boolean validId(Object value) {
return value instanceof Long;
}
}