Java tutorial
/** * Copyright 2013 Tommi S.E. Laukkanen * * 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.bubblecloud.ilves.ui.administrator.user; import com.vaadin.data.util.BeanItem; import com.vaadin.ui.Button; import com.vaadin.ui.Button.ClickEvent; import com.vaadin.ui.Button.ClickListener; import com.vaadin.ui.GridLayout; import com.vaadin.ui.HorizontalLayout; import org.bubblecloud.ilves.component.flow.AbstractFlowlet; import org.bubblecloud.ilves.component.grid.FieldDescriptor; import org.bubblecloud.ilves.component.grid.ValidatingEditor; import org.bubblecloud.ilves.component.grid.ValidatingEditorStateListener; import org.bubblecloud.ilves.model.GroupMember; import org.bubblecloud.ilves.site.SiteFields; import javax.persistence.EntityManager; import java.util.ArrayList; import java.util.List; /** * GroupMember edit Flowlet. * * @author Tommi S.E. Laukkanen */ public final class UserGroupMemberFlowlet extends AbstractFlowlet implements ValidatingEditorStateListener { /** Serial version UID. */ private static final long serialVersionUID = 1L; /** The entity manager. */ private EntityManager entityManager; /** The groupMember flow. */ private GroupMember entity; /** The entity form. */ private ValidatingEditor groupMemberEditor; /** The save button. */ private Button saveButton; /** The discard button. */ private Button discardButton; @Override public String getFlowletKey() { return "group-membership"; } @Override public boolean isDirty() { return groupMemberEditor.isModified(); } @Override public boolean isValid() { return groupMemberEditor.isValid(); } @Override public void initialize() { entityManager = getSite().getSiteContext().getObject(EntityManager.class); final GridLayout gridLayout = new GridLayout(1, 2); gridLayout.setSizeFull(); gridLayout.setMargin(false); gridLayout.setSpacing(true); gridLayout.setRowExpandRatio(1, 1f); setViewContent(gridLayout); final List<FieldDescriptor> fieldDescriptors = new ArrayList<FieldDescriptor>( SiteFields.getFieldDescriptors(GroupMember.class)); for (final FieldDescriptor fieldDescriptor : fieldDescriptors) { if ("user".equals(fieldDescriptor.getId())) { fieldDescriptors.remove(fieldDescriptor); break; } } groupMemberEditor = new ValidatingEditor(fieldDescriptors); groupMemberEditor.setCaption("GroupMember"); groupMemberEditor.addListener(this); gridLayout.addComponent(groupMemberEditor, 0, 0); final HorizontalLayout buttonLayout = new HorizontalLayout(); buttonLayout.setSpacing(true); gridLayout.addComponent(buttonLayout, 0, 1); saveButton = new Button("Save"); saveButton.setImmediate(true); buttonLayout.addComponent(saveButton); saveButton.addClickListener(new ClickListener() { /** Serial version UID. */ private static final long serialVersionUID = 1L; @Override public void buttonClick(final ClickEvent event) { groupMemberEditor.commit(); entityManager.getTransaction().begin(); try { entity = entityManager.merge(entity); entityManager.persist(entity); entityManager.getTransaction().commit(); //entityManager.detach(entity); } catch (final Throwable t) { if (entityManager.getTransaction().isActive()) { entityManager.getTransaction().rollback(); } throw new RuntimeException("Failed to save entity: " + entity, t); } } }); discardButton = new Button("Discard"); discardButton.setImmediate(true); buttonLayout.addComponent(discardButton); discardButton.addClickListener(new ClickListener() { /** Serial version UID. */ private static final long serialVersionUID = 1L; @Override public void buttonClick(final ClickEvent event) { groupMemberEditor.discard(); } }); } /** * Edit an existing groupMember. * @param entity entity to be edited. * @param newEntity true if entity to be edited is new. */ public void edit(final GroupMember entity, final boolean newEntity) { this.entity = entity; groupMemberEditor.setItem(new BeanItem<GroupMember>(entity), newEntity); } @Override public void editorStateChanged(final ValidatingEditor source) { if (isDirty()) { if (isValid()) { saveButton.setEnabled(true); } else { saveButton.setEnabled(false); } discardButton.setEnabled(true); } else { saveButton.setEnabled(false); discardButton.setEnabled(false); } } @Override public void enter() { } }