// Copyright 2004, 2005 The Apache Software Foundation
//
// 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 org.apache.tapestry.vlib.components;
import java.rmi.RemoteException;
import javax.ejb.FinderException;
import org.apache.hivemind.ApplicationRuntimeException;
import org.apache.tapestry.BaseComponent;
import org.apache.tapestry.IPage;
import org.apache.tapestry.IRequestCycle;
import org.apache.tapestry.annotations.InjectPage;
import org.apache.tapestry.annotations.InjectState;
import org.apache.tapestry.annotations.Message;
import org.apache.tapestry.annotations.Parameter;
import org.apache.tapestry.vlib.OperationsUser;
import org.apache.tapestry.vlib.Visit;
import org.apache.tapestry.vlib.ejb.Book;
import org.apache.tapestry.vlib.ejb.BorrowException;
import org.apache.tapestry.vlib.pages.Home;
import org.apache.tapestry.vlib.services.RemoteCallback;
/**
* Implements the Borrow link that appears on many pages. <table border=1>
* <tr>
* <th>Parameter</th>
* <th>Type</th>
* <th>Read / Write </th>
* <th>Required</th>
* <th>Default</th>
* <th>Description</th>
* </tr>
* <tr>
* <td>book</td>
* <td>{@link Book}</td>
* <td>R</td>
* <td>yes</td>
* <td> </td>
* <td>The book to create a link to. </td>
* </tr>
* </table>
* <p>
* Informal parameters are not allowed. A body is not allowed.
*
* @author Howard Lewis Ship
*/
public abstract class Borrow extends BaseComponent implements OperationsUser
{
@Parameter(required = true)
public abstract Book getBook();
@InjectState("visit")
public abstract Visit getVisit();
@InjectPage("Home")
public abstract Home getHome();
@Message
public abstract String borrowedBook(String title);
public boolean isLinkDisabled()
{
Visit visit = getVisit();
if (!visit.isUserLoggedIn())
return true;
// If the user is logged in, they can borrow it if they are
// not already holding it and aren't the owner.
Book book = getBook();
// If the book is not lendable, then disable the link.
if (!book.isLendable())
return true;
// Otherwise, disabled the link if already holding it.
return visit.isLoggedInUser(book.getHolderId());
}
public IPage borrow(final IRequestCycle cycle, final Integer bookId)
{
final Visit visit = getVisit();
final Home home = getHome();
RemoteCallback callback = new RemoteCallback()
{
public Object remoteCallback() throws RemoteException
{
try
{
Book book = getOperations().borrowBook(bookId, visit.getUserId());
home.setMessage(borrowedBook(book.getTitle()));
return null;
}
catch (BorrowException ex)
{
getErrorPresenter().presentError(ex.getMessage(), cycle);
return null;
}
catch (FinderException ex)
{
throw new ApplicationRuntimeException("Unable to find book or user.", ex);
}
}
};
getRemoteTemplate().doRemote(callback, "Error borrowing book.");
return home;
}
}