I use a quite similar approach as yours, but with different names. I'll post it here, so I think you can have some idea.
My way is to check the entity explicitly before merging it.
My JSF CRUD looks like this
xhtml
<?xml version="1.0" encoding="UTF-8" ?>
<!DOCTYPE html PUBLIC "-//W3C//DTD XHTML 1.0 Transitional//EN" "http://www.w3.org/TR/xhtml1/DTD/xhtml1-transitional.dtd">
<html xmlns="http://www.w3.org/1999/xhtml"
xmlns:f="http://java.sun.com/jsf/core"
xmlns:h="http://java.sun.com/jsf/html"
xmlns:ui="http://java.sun.com/jsf/facelets"
xmlns:p="http://primefaces.org/ui">
<h:head>
<meta http-equiv="Content-Type" content="text/html; charset=UTF-8" />
<title>DataSource Manager</title>
</h:head>
<h:body>
<h:form id="ds">
<p:spacer height="10" />
<p:fieldset legend="Insert/Edit Data Source">
<p:panel id="insertUpdateForm">
<h:panelGrid columns="2">
<p:outputLabel for="name" value="Data Source Name:" style="width:100px;"/>
<p:inputText id="name" value="#{dataSourceMB.dataSource.name}"/>
<p:outputLabel for="user" value="User:" style="width:100px;"/>
<p:inputText id="user" value="#{dataSourceMB.dataSource.user}"/>
<p:outputLabel for="driver" value="Driver:" style="width:100px;"/>
<p:inputText id="driver" value="#{dataSourceMB.dataSource.driver}" />
</h:panelGrid>
</p:panel>
<p:panel>
<p:commandButton value="Save" action="#{dataSourceMB.saveDataSource}" update="dsList,insertUpdateForm" />
<p:commandButton value="Clear" action="#{dataSourceMB.clearDataSource}" update="insertUpdateForm" />
<p:commandButton value="Test Connection" action="#{dataSourceMB.testConnection}"/>
</p:panel>
</p:fieldset>
<p:spacer height="10" />
<p:fieldset legend="Data Sources">
<p:panel>
<p:dataTable
var="ds"
value="#{dataSourceMB.listDataSources}"
paginator="true" rows="10"
paginatorTemplate="{RowsPerPageDropdown} {FirstPageLink} {PreviousPageLink} {CurrentPageReport} {NextPageLink} {LastPageLink}"
rowsPerPageTemplate="10,50,100"
id="dsList">
<p:column headerText="ID">
<h:outputText value="#{ds.id}" />
</p:column>
<p:column headerText="Name">
<h:outputText value="#{ds.name}" />
</p:column>
<p:column headerText="JDBC">
<h:outputText value="#{ds.jdbc} " />
</p:column>
<!-- check http://jqueryui.com/themeroller/ for icons -->
<p:column headerText="" style="width:2%">
<p:commandButton icon="ui-icon-pencil" action="#{dataSourceMB.editDataSource}" title="Edit" update=":ds:insertUpdateForm">
<f:setPropertyActionListener value="#{ds}" target="#{dataSourceMB.selectedDataSource}" />
</p:commandButton>
</p:column>
<p:column headerText="" style="width:2%">
<p:commandButton icon="ui-icon-trash" action="#{dataSourceMB.removeDataSource}" title="Remove" update=":ds:insertUpdateForm,dsList">
<f:setPropertyActionListener value="#{ds}" target="#{dataSourceMB.selectedDataSource}" />
</p:commandButton>
</p:column>
</p:dataTable>
</p:panel>
</p:fieldset>
</h:form>
</h:body>
</html>
my managed bean
import java.io.Serializable;
import java.util.List;
import javax.annotation.PostConstruct;
import javax.ejb.EJB;
import javax.faces.bean.ManagedBean;
import javax.faces.bean.ViewScoped;
import org.apache.log4j.Logger;
import DataSourceEJB;
import JSFUtilEJB;
import DataSource;
@ManagedBean
@ViewScoped
public class DataSourceMB implements Serializable {
private static final long serialVersionUID = 871363306742707990L;
private static Logger log = Logger.getLogger(DataSourceMB.class);
@EJB
private JSFUtilEJB jsfUtilEJB;
@EJB
private DataSourceEJB dataSourceEJB;
private DataSource dataSource;
private DataSource selectedDataSource;
private List<DataSource> listDataSources;
@PostConstruct
public void init() {
try {
this.dataSource = new DataSource();
this.listDataSources = this.dataSourceEJB.listDataSources();
} catch (Exception e) {
jsfUtilEJB.addErrorMessage(e,"Could not list");
}
}
public void removeDataSource(){
try {
this.dataSourceEJB.removeDataSource(this.selectedDataSource);
jsfUtilEJB.addInfoMessage("Removed "+this.selectedDataSource.getName());
if (this.dataSource != null && this.dataSource.getId() != null && this.dataSource.getId().equals(this.selectedDataSource.getId())){
this.dataSource = null;
}
this.listDataSources = this.dataSourceEJB.listDataSources();
} catch (Exception e) {
jsfUtilEJB.addErrorMessage(e,"Could not remove");
}
}
public void saveDataSource(){
try {
this.dataSourceEJB.saveDataSource(this.dataSource);
jsfUtilEJB.addInfoMessage("Saved "+this.dataSource.getName());
this.dataSource = new DataSource();
this.listDataSources = this.dataSourceEJB.listDataSources();
} catch (Exception e) {
jsfUtilEJB.addErrorMessage(e,"Could not save");
}
}
public void editDataSource(){
this.dataSource = this.selectedDataSource;
}
public void clearDataSource(){
this.dataSource = new DataSource();
}
public DataSource getDataSource() {
return dataSource;
}
public void setDataSource(DataSource dataSource) {
this.dataSource = dataSource;
}
public DataSource getSelectedDataSource() {
return selectedDataSource;
}
public void setSelectedDataSource(DataSource selectedDataSource) {
this.selectedDataSource = selectedDataSource;
}
public List<DataSource> getListDataSources() {
return listDataSources;
}
public void setListDataSources(List<DataSource> listDataSources) {
this.listDataSources = listDataSources;
}
}
my EJB
import java.io.IOException;
import java.sql.SQLException;
import java.util.List;
import javax.ejb.Stateless;
import javax.inject.Inject;
import DataSource;
@Stateless
public class DataSourceEJB {
@Inject
private BaseService baseService;
public List<DataSource> listDataSources() {
return this.baseService.getDataSourceDAO().getAll();
}
public void removeDataSource(DataSource ds) throws Exception {
DataSource a = this.baseService.getDataSourceDAO().find(ds.getId());
this.baseService.getDataSourceDAO().delete(a);
}
public void saveDataSource(DataSource ds) throws Exception {
DataSource a = this.baseService.getDataSourceDAO().find(ds.getId());
if (a == null){
this.baseService.getDataSourceDAO().add(ds);
}else{
this.baseService.getDataSourceDAO().edit(ds);
}
}
public DataSource getById(long id) {
return this.baseService.getDataSourceDAO().find(id);
}
public DataSource getByName(String name) {
return this.baseService.getDataSourceDAO().findByName(name);
}
}
DAO
public E find(Long id) {
return (E)entityManager.find(clazz, id);
}
public void add(E entity) throws Exception {
entityManager.persist(entity);
}
public E edit(E entity) throws Exception {
return entityManager.merge(entity);
}
public void delete(E entity) throws Exception {
entityManager.remove(entity);
}