Example Code for Deserialization Problem

TransactionalTaskExample

package com.myproject;

import com.hazelcast.core.HazelcastInstance;
import com.hazelcast.core.IMap;
import com.hazelcast.core.TransactionalMap;
import com.hazelcast.transaction.TransactionException;
import com.hazelcast.transaction.TransactionalTask;
import com.hazelcast.transaction.TransactionalTaskContext;

import java.io.Serializable;
import java.util.Map;
import java.util.Set;

public class TransactionalTaskExample {

	private IHazelcastClientFactory hazelcastClientFactory;

	public TransactionalTaskExample(final IHazelcastClientFactory hazelcastClientFactory){
		this.hazelcastClientFactory = hazelcastClientFactory;
	}

	public void storeSentenceWithWordFrequencies(final String key, final Sentence sentence) {

		final HazelcastInstance hazelcastClient = hazelcastClientFactory.getHazelcastClient();

		hazelcastClient.executeTransaction(new TransactionalTask() {
			@Override
			public Object execute(final TransactionalTaskContext context) throws TransactionException {
				final TransactionalMap<String, Sentence> sentences = context.getMap("sentences");
				final TransactionalMap<String, WordFrequency> wordFrequencies = context.getMap("wordFrequencies");

				//so I use a secondary IMap reference to same map for get and contains methods
				final IMap<String, WordFrequency> wordFrequenciesAsMap = hazelcastClient.getMap("wordFrequencies");
				
				sentences.put(key, sentence);

				final String[] words = sentence.getContent().split(" ");
				for (final String word : words) {

					if(! wordFrequenciesAsMap.containsKey(word)){
						wordFrequencies.put(word, new WordFrequency(1));
					} else{
						final WordFrequency wordFrequency = wordFrequenciesAsMap.get(word);
						wordFrequency.increaseFrequency();
						
						//This line updates the existing wordFrequency entry, when this line is executed;
						//same deserialization exception is throwed, 
						//maybe because it internally does a get (or contains or some reading operation) call to map for the existing entry???  
						wordFrequencies.put(word, wordFrequency);
					}

				}

				return null;
			}
		});
	}

	public void saveOrUpdateSentence(final String key, final Sentence sentence) {
		final HazelcastInstance hazelcastClient = hazelcastClientFactory.getHazelcastClient();
		hazelcastClient.executeTransaction(new TransactionalTask() {

			@Override
			public Object execute(final TransactionalTaskContext context) throws TransactionException {
				final TransactionalMap<String, Sentence> sentences = context.getMap("sentences");
				sentences.put(key, sentence);
				return null;
			}
		});
	}

	public Sentence getSentence(final String key) {
		final HazelcastInstance hazelcastClient = hazelcastClientFactory.getHazelcastClient();
		final IMap<String, Sentence> sentencesAsMap = hazelcastClient.getMap("sentences");
		return sentencesAsMap.get(key);
	}

	public void dumpAll(){
		final HazelcastInstance hazelcastClient = hazelcastClientFactory.getHazelcastClient();
		final IMap<String, Sentence> sentencesAsMap = hazelcastClient.getMap("sentences");
		final IMap<String, Sentence> wordFrequenciesAsMap = hazelcastClient.getMap("wordFrequencies");

		final Set<Map.Entry<String, Sentence>> sentenceEntries = sentencesAsMap.entrySet();

		System.out.println("Sentences");
		for (final Map.Entry<String, Sentence> entry : sentenceEntries) {
			System.out.println("key: " + entry.getKey() + " value: " + entry.getValue());
		}
		System.out.println();
		System.out.println("Word Frequencies");

		final Set<Map.Entry<String, Sentence>> wordFrequencyEntries = wordFrequenciesAsMap.entrySet();
		for (final Map.Entry<String, Sentence> entry : wordFrequencyEntries) {
			System.out.println("key: " + entry.getKey() + " value: " + entry.getValue());
		}

	}

	public static class Sentence implements Serializable {

		private static final long serialVersionUID = 1L;

		private String content;
		private String authorsName;

		public Sentence(final String content, final String authorsName){
			this.content = content;
			this.authorsName = authorsName;
		}

		public String getContent(){
			return content;
		}

		public String getAuthorsName(){
			return authorsName;
		}

		public void setAuthorsName(final String authorsName){
			this.authorsName = authorsName;
		}


		@Override
		public boolean equals(final Object o) {
			if (this == o) {
				return true;
			}
			if (!(o instanceof Sentence)) {
				return false;
			}

			final Sentence sentence = (Sentence) o;

			if (!authorsName.equals(sentence.authorsName)) {
				return false;
			}
			if (!content.equals(sentence.content)) {
				return false;
			}

			return true;
		}

		@Override
		public int hashCode() {
			int result = content.hashCode();
			result = 31 * result + authorsName.hashCode();
			return result;
		}

		@Override
		public String toString() {
			return "Sentence{" +
				   "content='" + content + '\'' +
				   ", authorsName='" + authorsName + '\'' +
				   '}';
		}
	}

	public static class WordFrequency implements Serializable {

		private static final long serialVersionUID = 1L;

		private int frequency;

		public WordFrequency(final int frequency){

			this.frequency = frequency;
		}

		public void increaseFrequency(){
			frequency += 1;
		}

		@Override
		public String toString() {
			return "WordFrequency{" +
				   "frequency=" + frequency +
				   '}';
		}
	}
}