/*
* Copyright (c) 2016 Couchbase, Inc.
*
* 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 com.couchbase.client.java;
import com.couchbase.client.core.message.kv.MutationToken;
import com.couchbase.client.java.document.Document;
import com.couchbase.client.java.document.json.JsonArray;
import com.couchbase.client.java.document.json.JsonObject;
import com.couchbase.client.java.subdoc.DocumentFragment;
import java.util.ArrayList;
import java.util.Iterator;
import java.util.List;
import java.util.ListIterator;
/**
* Aggregation of one or more {@link MutationToken MutationToken} into one {@link MutationState}.
*
* @author Michael Nitschinger
* @since 2.3.0
*/
public class MutationState implements Iterable<MutationToken> {
private final List<MutationToken> tokens;
private MutationState() {
this.tokens = new ArrayList<MutationToken>();
}
/**
* Create a {@link MutationState} from one or more {@link Document Documents}.
*
* @param documents the documents where the tokens are extracted from.
* @return the initialized {@link MutationState}.
*/
public static MutationState from(Document... documents) {
return new MutationState().add(documents);
}
/**
* Create a {@link MutationState} from one or more {@link DocumentFragment DocumentFragments}.
*
* @param documentFragments the document fragments where the tokens are extracted from.
* @return the initialized {@link MutationState}.
*/
public static MutationState from(DocumentFragment... documentFragments) {
return new MutationState().add(documentFragments);
}
/**
* Add one or more {@link Document Documents} to this {@link MutationState}.
*
* @param documents the documents where the tokens are extracted from.
* @return the modified {@link MutationState}.
*/
public MutationState add(Document... documents) {
if (documents == null || documents.length == 0) {
throw new IllegalArgumentException("At least one Document must be provided.");
}
for (Document d : documents) {
addToken(d.mutationToken());
}
return this;
}
/**
* Add one or more {@link DocumentFragment DocumentFragments} to this {@link MutationState}.
*
* @param documentFragments the fragments where the tokens are extracted from.
* @return the modified {@link MutationState}.
*/
public MutationState add(DocumentFragment... documentFragments) {
if (documentFragments == null || documentFragments.length == 0) {
throw new IllegalArgumentException("At least one DocumentFragment must be provided.");
}
for (DocumentFragment d : documentFragments) {
addToken(d.mutationToken());
}
return this;
}
/**
* Adds all the internal state from the given {@link MutationState} onto the called one.
*
* @param mutationState the state from which the tokens are applied from.
* @return the modified {@link MutationState}.
*/
public MutationState add(MutationState mutationState) {
for(MutationToken token : mutationState) {
addToken(token);
}
return this;
}
/**
* Helper method to check the incoming token and store it if needed.
*
* Note that the token is only stored if it doesn't exist for the given vbucket already or the given sequence
* number is higher than the one stored.
*
* @param token the token to check and maybe store.
*/
private void addToken(final MutationToken token) {
if (token != null) {
ListIterator<MutationToken> tokenIterator = tokens.listIterator();
while (tokenIterator.hasNext()) {
MutationToken t = tokenIterator.next();
if (t.vbucketID() == token.vbucketID() && t.bucket().equals(token.bucket())) {
if (token.sequenceNumber() > t.sequenceNumber()) {
tokenIterator.set(token);
}
return;
}
}
tokens.add(token);
}
}
@Override
public Iterator<MutationToken> iterator() {
return tokens.iterator();
}
/**
* Exports the {@link MutationState} into a universal format, which can be used either to serialize it into
* a N1QL query or to send it over the network to a different application/SDK.
*
* @return the exported {@link JsonObject}.
*/
public JsonObject export() {
JsonObject result = JsonObject.create();
for (MutationToken token : tokens) {
JsonObject bucket = result.getObject(token.bucket());
if (bucket == null) {
bucket = JsonObject.create();
result.put(token.bucket(), bucket);
}
bucket.put(
String.valueOf(token.vbucketID()),
JsonArray.from(token.sequenceNumber(), String.valueOf(token.vbucketUUID()))
);
}
return result;
}
/**
* Exports the {@link MutationState} into a format recognized by the FTS search engine.
*
* @return the exported {@link JsonObject} for one FTS index.
*/
public JsonObject exportForFts() {
JsonObject result = JsonObject.create();
for (MutationToken token : tokens) {
String tokenKey = token.vbucketID() + "/" + token.vbucketUUID();
Long seqno = result.getLong(tokenKey);
if (seqno == null || seqno < token.sequenceNumber()) {
result.put(tokenKey, token.sequenceNumber());
}
}
return result;
}
/**
* Create a {@link MutationState} from the serialized state.
*
* @param source the source state, serialized.
* @return the created {@link MutationState}.
*/
public static MutationState from(String source) {
return from(JsonObject.fromJson(source));
}
/**
* Create a {@link MutationState} from the serialized state.
*
* @param source the source state, serialized.
* @return the created {@link MutationState}.
*/
public static MutationState from(JsonObject source) {
try {
MutationState state = new MutationState();
for (String bucketName : source.getNames()) {
JsonObject bucket = source.getObject(bucketName);
for (String vbid : bucket.getNames()) {
JsonArray values = bucket.getArray(vbid);
state.addToken(new MutationToken(
Long.parseLong(vbid),
Long.parseLong(values.getString(1)),
values.getLong(0),
bucketName
));
}
}
return state;
} catch (Exception ex) {
throw new IllegalStateException("Could not import MutationState from JSON.", ex);
}
}
@Override
public boolean equals(Object o) {
if (this == o) return true;
if (o == null || getClass() != o.getClass()) return false;
MutationState state = (MutationState) o;
return tokens.containsAll(state.tokens) && state.tokens.containsAll(tokens);
}
@Override
public int hashCode() {
return tokens.hashCode();
}
@Override
public String toString() {
return "MutationState{tokens=" + tokens + '}';
}
}