MVVM CRUD with Spring 3.1 and Hibernate 4 and ZK - Part 5 ~ Requirement Constraints

This article focus on Delete function.

In the part 4 article, we have seen how to open the CRUD form in Read only. Now we will see how to delete the existing address entry from the database.

Step 1:

Let us modify the AddressList.zul file to include one more Button to delete the selected address. The modified addressList.zul file as follows

<?page title="Address List" contentType="text/html;charset=UTF-8"?>
<zk>
	<window id="addressList" title="Address List" border="none"
		apply="org.zkoss.bind.BindComposer"
		viewModel="@id('vm') @init('zkoss.vm.AddressListVM')">
		<separator />
		<button label="New Address" onClick="@command('onAddNew')"></button>
		<separator />
		<listbox id="" mold="paging" pageSize="11" pagingPosition="top"
			selectedItem="@bind(vm.selectedItem)" model="@load(vm.dataSet)">
			<listhead sizable="true">
				<listheader label="Full Name" sortDirection="ascending"
					sort="auto(fullName)" />
				<listheader label="Email" sort="auto(email)" />
				<listheader label="Mobile" sort="auto(mobile)" />
				<listheader label="Action" />
			</listhead>
			<template name="model" var="p1">
				<listitem>
					<listcell label="@load(p1.fullName)" />
					<listcell label="@load(p1.email)" />
					<listcell label="@load(p1.mobile)" />
					<listcell>
						<hbox spacing="20px">
							<button label="Edit"
								onClick="@command('onEdit',addressRecord=p1)">
							</button>
							<button label="View"
								onClick="@command('openAsReadOnly',addressRecord=p1)">
							</button>
							<button label="Delete"
								onClick="@command('onDelete',addressRecord=p1)">
							</button>
						</hbox>
					</listcell>
				</listitem>
			</template>
		</listbox>
	</window>
</zk>

Step 2:

Let us modify AddressListVM.java as follows

package zkoss.vm;

import java.util.HashMap;
import java.util.List;

import org.springframework.dao.DataAccessException;
import org.zkoss.bind.BindUtils;
import org.zkoss.bind.annotation.AfterCompose;
import org.zkoss.bind.annotation.BindingParam;
import org.zkoss.bind.annotation.Command;
import org.zkoss.bind.annotation.ContextParam;
import org.zkoss.bind.annotation.ContextType;
import org.zkoss.bind.annotation.GlobalCommand;
import org.zkoss.bind.annotation.NotifyChange;
import org.zkoss.zk.ui.Component;
import org.zkoss.zk.ui.Executions;
import org.zkoss.zk.ui.event.Event;
import org.zkoss.zk.ui.event.EventListener;
import org.zkoss.zk.ui.select.Selectors;
import org.zkoss.zk.ui.select.annotation.WireVariable;
import org.zkoss.zkplus.spring.SpringUtil;
import org.zkoss.zul.Messagebox;

import AddressBook.domain.AddressBook;
import AddressBook.service.CRUDService;

public class AddressListVM {

	@WireVariable
	private CRUDService CRUDService;

	private AddressBook selectedItem;
	private List<AddressBook> allReordsInDB = null;
	private Integer selectedItemIndex;

	public AddressBook getSelectedItem() {
		return selectedItem;
	}

	public void setSelectedItem(AddressBook selectedItem) {
		this.selectedItem = selectedItem;
	}

	public Integer getSelectedItemIndex() {
		return selectedItemIndex;
	}

	public void setSelectedItemIndex(Integer selectedItemIndex) {
		this.selectedItemIndex = selectedItemIndex;
	}

	@AfterCompose
	public void initSetup(@ContextParam(ContextType.VIEW) Component view) {
		Selectors.wireComponents(view, this, false);
		CRUDService = (CRUDService) SpringUtil.getBean("CRUDService");
		allReordsInDB = CRUDService.getAll(AddressBook.class);
	}

	public List<AddressBook> getDataSet() {
		return allReordsInDB;
	}

	@Command
	public void onAddNew() {
		final HashMap<String, Object> map = new HashMap<String, Object>();
		map.put("selectedRecord", null);
		map.put("recordMode", "NEW");
		Executions.createComponents("AddressCRUD.zul", null, map);
	}

	@Command
	public void onEdit(@BindingParam("addressRecord") AddressBook addressBook) {
		final HashMap<String, Object> map = new HashMap<String, Object>();
		this.selectedItem = addressBook;
		map.put("selectedRecord", addressBook);
		map.put("recordMode", "EDIT");
		setSelectedItemIndex(allReordsInDB.indexOf(selectedItem));
		Executions.createComponents("AddressCRUD.zul", null, map);
	}

	@Command
	public void openAsReadOnly(
			@BindingParam("addressRecord") AddressBook addressBook) {
		final HashMap<String, Object> map = new HashMap<String, Object>();
		this.selectedItem = addressBook;
		map.put("selectedRecord", addressBook);
		map.put("recordMode", "READ");
		Executions.createComponents("AddressCRUD.zul", null, map);
	}

	@SuppressWarnings({ "rawtypes", "unchecked" })
	@Command
	public void onDelete(@BindingParam("addressRecord") AddressBook addressBook) {
		int OkCancel;
		this.selectedItem = addressBook;
		String str = "The Selected  \"" + addressBook.getFullName()
				+ "\" will be deleted.";
		OkCancel = Messagebox.show(str, "Confirm", Messagebox.OK
				| Messagebox.CANCEL, Messagebox.QUESTION);
		if (OkCancel == Messagebox.CANCEL) {
			return;
		}

		str = "The \""
				+ addressBook.getFullName()
				+ "\" will be permanently deleted and the action cannot be undone.";

		Messagebox.show(str, "Confirm", Messagebox.OK | Messagebox.CANCEL,
				Messagebox.QUESTION, new EventListener() {
					public void onEvent(Event event) throws Exception {
						if (((Integer) event.getData()).intValue() == Messagebox.OK) {

							CRUDService.delete(selectedItem);
							allReordsInDB.remove(allReordsInDB
									.indexOf(selectedItem));
							BindUtils.postNotifyChange(null, null,
									AddressListVM.this, "dataSet");

						}
					}
				});
	}

	// note this will be executed from AddressListCRUDVM.java

	@GlobalCommand
	@NotifyChange("dataSet")
	public void refreshList(
			@BindingParam("selectedRecord") AddressBook addressbook,
			@BindingParam("recordMode") String recordMode) {
		if (recordMode.equals("NEW")) {
			allReordsInDB.add(addressbook);
		}

		if (recordMode.equals("EDIT")) {
			allReordsInDB.set(this.selectedItemIndex, addressbook);
		}
	}

}

As you can see, we have added another method called onDelete and handle the delete function

Step 3:

Now we will add the delete method in 4 java files (service and dao layer).
CRUDDao.java

package AddressBook.dao;

import java.util.List;

public interface CRUDDao {
	<T> List<T> getAll(Class<T> klass);
	<T> void Save(T klass);
	<T> void delete(T klass);
}

CRUDDaoImpl.java

package AddressBook.dao;

import java.util.List;

import org.hibernate.Session;
import org.hibernate.SessionFactory;
import org.springframework.beans.factory.annotation.Autowired;
import org.springframework.stereotype.Repository;

@Repository
public class CRUDDaoImpl implements CRUDDao {

	@Autowired
	SessionFactory sessionFactory;

	@SuppressWarnings("unchecked")
	public <T> List<T> getAll(Class<T> klass) {
		return getCurrentSession().createQuery("from " + klass.getName())
				.list();
	}

	protected final Session getCurrentSession() {
		return sessionFactory.getCurrentSession();
	}

	public <T> void Save(T klass) {
		getCurrentSession().save(klass);
	}

	public <T> void delete(T klass) {
		getCurrentSession().delete(klass);
		
	}

}

CRUDService.java

package AddressBook.service;

import java.util.List;

public interface CRUDService {
	<T> List<T> getAll(Class<T> klass);
	<T> void Save(T klass);
	<T> void delete(T klass);
}

CRUDServiceImpl.java

package AddressBook.service;

import java.util.List;
import org.springframework.beans.factory.annotation.Autowired;
import org.springframework.stereotype.Service;
import org.springframework.transaction.annotation.Transactional;

import AddressBook.dao.CRUDDao;

@Service
public class CRUDServiceImpl implements CRUDService {

	@Autowired
	private CRUDDao CRUDDao;

	@Transactional(readOnly = true)
	public <T> List<T> getAll(Class<T> klass) {
		return CRUDDao.getAll(klass);
	}

	@Transactional
	public <T> void Save(T klass) {
		CRUDDao.Save(klass);
	}

	@Transactional
	public <T> void delete(T klass) {
		CRUDDao.delete(klass);
	}

}

Step 5

Now we can run addresslist.zul

You can download the source here.

Requirement Constraints

Tuesday, 5 February 2013