package uk.co.his.experiment;

import java.util.ArrayList;
import java.util.List;

import javax.persistence.ElementCollection;
import javax.persistence.Entity;
import javax.persistence.Id;
import javax.persistence.PostLoad;
import javax.persistence.Transient;

@Entity
public class LostOuter {
	@Id
	private Long id;
	
	@ElementCollection
	private List<String> commentsA = new ArrayList<String>();
	
	@ElementCollection
	private List<String> commentsB = new ArrayList<String>();
	
	public LostOuter() 
	{
		System.err.println("Constructing a LostOuter");
		commentsAWrapper = new ConfusedInnerA();
		commentsBWrapper = new ConfusedInnerB();
	}
	
	@Transient
	private transient ConfusedInnerA commentsAWrapper = new ConfusedInnerA();
	
	private class ConfusedInnerA
	{
		void addComment(String comment)
		{
			commentsA.add(comment);
		}
		
		LostOuter getOuter() { return LostOuter.this; }
	}
	
	@SuppressWarnings("unused")
	@PostLoad
	private void postLoadStitchUp()
	{
		commentsAWrapper = new ConfusedInnerA();
	}
	
	@Transient
	private transient ConfusedInnerB commentsBWrapper = new ConfusedInnerB();
	
	private class ConfusedInnerB
	{
		void addComment(String comment)
		{
			commentsB.add(comment);
		}
		
		LostOuter getOuter() { return LostOuter.this; }
	}
	
	public void addComment(String comment)
	{
		commentsAWrapper.addComment(comment);
		commentsBWrapper.addComment(comment);
	}
	
	public String getCurrentComments()
	{
		StringBuilder str = new StringBuilder();
		
		if(commentsAWrapper.getOuter() != this)
		{
			str.append("Oh no! what has happened to my commentsAWrapper?\n");
		}
		if(commentsBWrapper.getOuter() != this)
		{
			str.append("Oh no! what has happened to my commentsBWrapper?\n");
		}
		str.append("commentsA:\n");
		for (String comment : commentsA) {
			str.append("\t" + comment + "\n");
		}
		str.append("commentsB:\n");
		for (String comment : commentsB) {
			str.append("\t" + comment + "\n");
		}
		str.append("==========================\n");
		return str.toString();
	}
	
	public Long getId() {
		return id;
	}

	public void setId(Long id) {
		this.id = id;
	}
}

<?xml version="1.0" encoding="UTF-8"?>
<persistence xmlns="http://java.sun.com/xml/ns/persistence" xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance" version="2.0" xsi:schemaLocation="http://java.sun.com/xml/ns/persistence http://java.sun.com/xml/ns/persistence/persistence_2_0.xsd">
<persistence-unit name="ExperimentjndiPU" transaction-type="JTA">
<provider>org.eclipse.persistence.jpa.PersistenceProvider</provider>
<jta-data-source>ExperimentDB</jta-data-source>
<properties/>
</persistence-unit>
</persistence>