Java tutorial
/** * Copyright (C) 2009 GIP RECIA http://www.recia.fr * @Author (C) 2009 GIP RECIA <contact@recia.fr> * @Contributor (C) 2009 SOPRA http://www.sopragroup.com/ * @Contributor (C) 2011 Pierre Legay <pierre.legay@recia.fr> * * 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. */ /* * Licensed to the Apache Software Foundation (ASF) under one * or more contributor license agreements. See the NOTICE file * distributed with this work for additional information * regarding copyright ownership. The ASF licenses this file * to you 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.myfaces.application.jsp; import org.apache.commons.collections.map.ReferenceMap; import org.apache.commons.lang.builder.EqualsBuilder; import org.apache.commons.lang.builder.HashCodeBuilder; import org.apache.commons.logging.Log; import org.apache.commons.logging.LogFactory; import org.apache.myfaces.application.MyfacesStateManager; import org.apache.myfaces.application.TreeStructureManager; import org.apache.myfaces.renderkit.MyfacesResponseStateManager; import org.apache.myfaces.shared_impl.renderkit.ViewSequenceUtils; import org.apache.myfaces.shared_impl.util.MyFacesObjectInputStream; import javax.faces.FactoryFinder; import javax.faces.application.StateManager; import javax.faces.component.NamingContainer; import javax.faces.component.UIComponent; import javax.faces.component.UIViewRoot; import javax.faces.context.ExternalContext; import javax.faces.context.FacesContext; import javax.faces.render.RenderKit; import javax.faces.render.RenderKitFactory; import javax.faces.render.ResponseStateManager; import java.io.*; import java.util.*; import java.util.zip.GZIPInputStream; import java.util.zip.GZIPOutputStream; /** * Default StateManager implementation for use when views are defined * via tags in JSP pages. * * @author Thomas Spiegl (latest modification by $Author: grantsmith $) * @author Manfred Geiler * @version $Revision: 472792 $ $Date: 2006-11-09 07:34:47 +0100 (Do, 09 Nov 2006) $ */ public class JspStateManagerImpl extends MyfacesStateManager { private static final Log log = LogFactory.getLog(JspStateManagerImpl.class); private static final String SERIALIZED_VIEW_SESSION_ATTR = JspStateManagerImpl.class.getName() + ".SERIALIZED_VIEW"; private static final String SERIALIZED_VIEW_REQUEST_ATTR = JspStateManagerImpl.class.getName() + ".SERIALIZED_VIEW"; private static final String RESTORED_SERIALIZED_VIEW_REQUEST_ATTR = JspStateManagerImpl.class.getName() + ".RESTORED_SERIALIZED_VIEW"; /** * Only applicable if state saving method is "server" (= default). * Defines the amount (default = 20) of the latest views are stored in session. */ /** * Only applicable if state saving method is "server" (= default). * Defines the amount (default = 20) of the latest views are stored in session. */ private static final String NUMBER_OF_VIEWS_IN_SESSION_PARAM = "org.apache.myfaces.NUMBER_OF_VIEWS_IN_SESSION"; /** * Default value for <code>org.apache.myfaces.NUMBER_OF_VIEWS_IN_SESSION</code> context parameter. */ /** * Default value for <code>org.apache.myfaces.NUMBER_OF_VIEWS_IN_SESSION</code> context parameter. */ private static final int DEFAULT_NUMBER_OF_VIEWS_IN_SESSION = 20; /** * Only applicable if state saving method is "server" (= default). * If <code>true</code> (default) the state will be serialized to a byte stream before it is written to the session. * If <code>false</code> the state will not be serialized to a byte stream. */ private static final String SERIALIZE_STATE_IN_SESSION_PARAM = "org.apache.myfaces.SERIALIZE_STATE_IN_SESSION"; /** * Only applicable if state saving method is "server" (= default) and if <code>org.apache.myfaces.SERIALIZE_STATE_IN_SESSION</code> is <code>true</code> (= default). * If <code>true</code> (default) the serialized state will be compressed before it is written to the session. * If <code>false</code> the state will not be compressed. */ private static final String COMPRESS_SERVER_STATE_PARAM = "org.apache.myfaces.COMPRESS_STATE_IN_SESSION"; /** * Default value for <code>org.apache.myfaces.COMPRESS_STATE_IN_SESSION</code> context parameter. */ private static final boolean DEFAULT_COMPRESS_SERVER_STATE_PARAM = true; /** * Default value for <code>org.apache.myfaces.SERIALIZE_STATE_IN_SESSION</code> context parameter. */ private static final boolean DEFAULT_SERIALIZE_STATE_IN_SESSION = true; private static final int UNCOMPRESSED_FLAG = 0; private static final int COMPRESSED_FLAG = 1; private RenderKitFactory _renderKitFactory = null; public JspStateManagerImpl() { if (log.isTraceEnabled()) log.trace("New JspStateManagerImpl instance created"); } protected Object getComponentStateToSave(FacesContext facesContext) { if (log.isTraceEnabled()) log.trace("Entering getComponentStateToSave"); UIViewRoot viewRoot = facesContext.getViewRoot(); if (viewRoot.isTransient()) { return null; } Object serializedComponentStates = viewRoot.processSaveState(facesContext); //Locale is a state attribute of UIViewRoot and need not be saved explicitly if (log.isTraceEnabled()) log.trace("Exiting getComponentStateToSave"); return serializedComponentStates; } /** * Return an object which contains info about the UIComponent type * of each node in the view tree. This allows an identical UIComponent * tree to be recreated later, though all the components will have * just default values for their members. */ protected Object getTreeStructureToSave(FacesContext facesContext) { if (log.isTraceEnabled()) log.trace("Entering getTreeStructureToSave"); UIViewRoot viewRoot = facesContext.getViewRoot(); if (viewRoot.isTransient()) { return null; } TreeStructureManager tsm = new TreeStructureManager(); Object retVal = tsm.buildTreeStructureToSave(viewRoot); if (log.isTraceEnabled()) log.trace("Exiting getTreeStructureToSave"); return retVal; } /** * Given a tree of UIComponent objects created the default constructor * for each node, retrieve saved state info (from either the client or * the server) and walk the tree restoring the members of each node * from the saved state information. */ protected void restoreComponentState(FacesContext facesContext, UIViewRoot uiViewRoot, String renderKitId) { if (log.isTraceEnabled()) log.trace("Entering restoreComponentState"); //=========================================== // first, locate the saved state information //=========================================== Object serializedComponentStates; if (isSavingStateInClient(facesContext)) { RenderKit renderKit = getRenderKitFactory().getRenderKit(facesContext, renderKitId); ResponseStateManager responseStateManager = renderKit.getResponseStateManager(); serializedComponentStates = responseStateManager.getComponentStateToRestore(facesContext); if (serializedComponentStates == null) { log.error("No serialized component state found in client request!"); // mark UIViewRoot invalid by resetting view id uiViewRoot.setViewId(null); return; } } else { String viewId = uiViewRoot.getViewId(); String sequenceStr = getSequenceString(facesContext, renderKitId, viewId); SerializedView serializedView = getSerializedViewFromServletSession(facesContext, viewId, sequenceStr); if (serializedView == null) { log.error("No serialized view found in server session!"); // mark UIViewRoot invalid by resetting view id uiViewRoot.setViewId(null); return; } serializedComponentStates = serializedView.getState(); if (serializedComponentStates == null) { log.error("No serialized component state found in server session!"); return; } } if (uiViewRoot.getRenderKitId() == null) { //Just to be sure... uiViewRoot.setRenderKitId(renderKitId); } // now ask the view root component to restore its state uiViewRoot.processRestoreState(facesContext, serializedComponentStates); if (log.isTraceEnabled()) log.trace("Exiting restoreComponentState"); } /** * See getTreeStructureToSave. */ protected UIViewRoot restoreTreeStructure(FacesContext facesContext, String viewId, String renderKitId) { if (log.isTraceEnabled()) log.trace("Entering restoreTreeStructure"); UIViewRoot uiViewRoot; if (isSavingStateInClient(facesContext)) { //reconstruct tree structure from request RenderKit rk = getRenderKitFactory().getRenderKit(facesContext, renderKitId); ResponseStateManager responseStateManager = rk.getResponseStateManager(); Object treeStructure = responseStateManager.getTreeStructureToRestore(facesContext, viewId); if (treeStructure == null) { if (log.isDebugEnabled()) log.debug("Exiting restoreTreeStructure - No tree structure state found in client request"); return null; } TreeStructureManager tsm = new TreeStructureManager(); uiViewRoot = tsm.restoreTreeStructure((TreeStructureManager.TreeStructComponent) treeStructure); if (log.isTraceEnabled()) log.trace("Tree structure restored from client request"); } else { String sequenceStr = getSequenceString(facesContext, renderKitId, viewId); //reconstruct tree structure from ServletSession SerializedView serializedView = getSerializedViewFromServletSession(facesContext, viewId, sequenceStr); if (serializedView == null) { if (log.isDebugEnabled()) log.debug("Exiting restoreTreeStructure - No serialized view found in server session!"); return null; } Object treeStructure = serializedView.getStructure(); if (treeStructure == null) { if (log.isDebugEnabled()) log.debug( "Exiting restoreTreeStructure - No tree structure state found in server session, former UIViewRoot must have been transient"); return null; } TreeStructureManager tsm = new TreeStructureManager(); uiViewRoot = tsm .restoreTreeStructure((TreeStructureManager.TreeStructComponent) serializedView.getStructure()); if (log.isTraceEnabled()) log.trace("Tree structure restored from server session"); } if (log.isTraceEnabled()) log.trace("Exiting restoreTreeStructure"); return uiViewRoot; } private String getSequenceString(FacesContext facesContext, String renderKitId, String viewId) { RenderKit rk = getRenderKitFactory().getRenderKit(facesContext, renderKitId); ResponseStateManager responseStateManager = rk.getResponseStateManager(); String sequenceStr = (String) responseStateManager.getTreeStructureToRestore(facesContext, viewId); return sequenceStr; } public UIViewRoot restoreView(FacesContext facescontext, String viewId, String renderKitId) { if (log.isTraceEnabled()) log.trace("Entering restoreView"); UIViewRoot uiViewRoot = restoreTreeStructure(facescontext, viewId, renderKitId); if (uiViewRoot != null) { uiViewRoot.setViewId(viewId); restoreComponentState(facescontext, uiViewRoot, renderKitId); String restoredViewId = uiViewRoot.getViewId(); if (restoredViewId == null || !(restoredViewId.equals(viewId))) { if (log.isTraceEnabled()) log.trace("Exiting restoreView - restored view is null."); return null; } } if (log.isTraceEnabled()) log.trace("Exiting restoreView"); return uiViewRoot; } public SerializedView saveSerializedView(FacesContext facesContext) throws IllegalStateException { if (log.isTraceEnabled()) log.trace("Entering saveSerializedView"); checkForDuplicateIds(facesContext, facesContext.getViewRoot(), new HashSet()); if (log.isTraceEnabled()) log.trace("Processing saveSerializedView - Checked for duplicate Ids"); ExternalContext externalContext = facesContext.getExternalContext(); // SerializedView already created before within this request? SerializedView serializedView = (SerializedView) externalContext.getRequestMap() .get(SERIALIZED_VIEW_REQUEST_ATTR); if (serializedView == null) { if (log.isTraceEnabled()) log.trace("Processing saveSerializedView - create new serialized view"); // first call to saveSerializedView --> create SerializedView Object treeStruct = getTreeStructureToSave(facesContext); Object compStates = getComponentStateToSave(facesContext); serializedView = new StateManager.SerializedView(treeStruct, compStates); externalContext.getRequestMap().put(SERIALIZED_VIEW_REQUEST_ATTR, serializedView); if (log.isTraceEnabled()) log.trace("Processing saveSerializedView - new serialized view created"); } if (!isSavingStateInClient(facesContext)) { if (log.isTraceEnabled()) log.trace("Processing saveSerializedView - server-side state saving - save state"); //save state in server session saveSerializedViewInServletSession(facesContext, serializedView); if (log.isTraceEnabled()) log.trace("Exiting saveSerializedView - server-side state saving - saved state"); Integer sequence = ViewSequenceUtils.getViewSequence(facesContext); return new SerializedView(sequence.toString(), null); } if (log.isTraceEnabled()) log.trace("Exiting saveSerializedView - client-side state saving"); return serializedView; } private static void checkForDuplicateIds(FacesContext context, UIComponent component, Set ids) { String id = component.getId(); if (id != null && !ids.add(id)) { throw new IllegalStateException("Client-id : " + id + " is duplicated in the faces tree. Component : " + component.getClientId(context) + ", path: " + getPathToComponent(component)); } Iterator it = component.getFacetsAndChildren(); boolean namingContainer = component instanceof NamingContainer; while (it.hasNext()) { UIComponent kid = (UIComponent) it.next(); if (namingContainer) { checkForDuplicateIds(context, kid, new HashSet()); } else { checkForDuplicateIds(context, kid, ids); } } } private static String getPathToComponent(UIComponent component) { StringBuffer buf = new StringBuffer(); if (component == null) { buf.append("{Component-Path : "); buf.append("[null]}"); return buf.toString(); } getPathToComponent(component, buf); buf.insert(0, "{Component-Path : "); buf.append("}"); return buf.toString(); } private static void getPathToComponent(UIComponent component, StringBuffer buf) { if (component == null) return; StringBuffer intBuf = new StringBuffer(); intBuf.append("[Class: "); intBuf.append(component.getClass().getName()); if (component instanceof UIViewRoot) { intBuf.append(",ViewId: "); intBuf.append(((UIViewRoot) component).getViewId()); } else { intBuf.append(",Id: "); intBuf.append(component.getId()); } intBuf.append("]"); buf.insert(0, intBuf.toString()); if (component != null) { getPathToComponent(component.getParent(), buf); } } public void writeState(FacesContext facesContext, SerializedView serializedView) throws IOException { if (log.isTraceEnabled()) log.trace("Entering writeState"); if (log.isTraceEnabled()) log.trace( "Processing writeState - either client-side (full state) or server-side (partial information; e.g. sequence)"); if (serializedView != null) { UIViewRoot uiViewRoot = facesContext.getViewRoot(); //save state in response (client-side: full state; server-side: sequence) RenderKit renderKit = getRenderKitFactory().getRenderKit(facesContext, uiViewRoot.getRenderKitId()); renderKit.getResponseStateManager().writeState(facesContext, serializedView); if (log.isTraceEnabled()) log.trace("Exiting writeState"); } } /** * MyFaces extension * * @param facesContext * @param serializedView * @throws IOException */ public void writeStateAsUrlParams(FacesContext facesContext, SerializedView serializedView) throws IOException { if (log.isTraceEnabled()) log.trace("Entering writeStateAsUrlParams"); if (isSavingStateInClient(facesContext)) { if (log.isTraceEnabled()) log.trace("Processing writeStateAsUrlParams - client-side state saving writing state"); UIViewRoot uiViewRoot = facesContext.getViewRoot(); //save state in response (client) RenderKit renderKit = getRenderKitFactory().getRenderKit(facesContext, uiViewRoot.getRenderKitId()); ResponseStateManager responseStateManager = renderKit.getResponseStateManager(); if (responseStateManager instanceof MyfacesResponseStateManager) { ((MyfacesResponseStateManager) responseStateManager).writeStateAsUrlParams(facesContext, serializedView); } else { log.error("ResponseStateManager of render kit " + uiViewRoot.getRenderKitId() + " is no MyfacesResponseStateManager and does not support saving state in url parameters."); } } if (log.isTraceEnabled()) log.trace("Exiting writeStateAsUrlParams"); } //helpers protected RenderKitFactory getRenderKitFactory() { if (_renderKitFactory == null) { _renderKitFactory = (RenderKitFactory) FactoryFinder.getFactory(FactoryFinder.RENDER_KIT_FACTORY); } return _renderKitFactory; } protected void saveSerializedViewInServletSession(FacesContext context, SerializedView serializedView) { Map sessionMap = context.getExternalContext().getSessionMap(); SerializedViewCollection viewCollection = (SerializedViewCollection) sessionMap .get(SERIALIZED_VIEW_SESSION_ATTR); if (viewCollection == null) { viewCollection = new SerializedViewCollection(); sessionMap.put(SERIALIZED_VIEW_SESSION_ATTR, viewCollection); } viewCollection.add(context, serializeView(context, serializedView)); // replace the value to notify the container about the change sessionMap.put(SERIALIZED_VIEW_SESSION_ATTR, viewCollection); } protected SerializedView getSerializedViewFromServletSession(FacesContext context, String viewId, String sequenceStr) { ExternalContext externalContext = context.getExternalContext(); Map requestMap = externalContext.getRequestMap(); SerializedView serializedView = null; if (requestMap.containsKey(RESTORED_SERIALIZED_VIEW_REQUEST_ATTR)) { serializedView = (SerializedView) requestMap.get(RESTORED_SERIALIZED_VIEW_REQUEST_ATTR); } else { SerializedViewCollection viewCollection = (SerializedViewCollection) externalContext.getSessionMap() .get(SERIALIZED_VIEW_SESSION_ATTR); if (viewCollection != null) { Integer sequence = null; if (sequenceStr == null) { // use latest sequence sequence = ViewSequenceUtils.getCurrentSequence(context); } else { sequence = new Integer(sequenceStr); } if (sequence != null) { Object state = viewCollection.get(sequence, viewId); if (state != null) { serializedView = deserializeView(state); } } } requestMap.put(RESTORED_SERIALIZED_VIEW_REQUEST_ATTR, serializedView); ViewSequenceUtils.nextViewSequence(context); } return serializedView; } protected Object serializeView(FacesContext context, SerializedView serializedView) { if (log.isTraceEnabled()) log.trace("Entering serializeView"); if (isSerializeStateInSession(context)) { if (log.isTraceEnabled()) log.trace("Processing serializeView - serialize state in session"); ByteArrayOutputStream baos = new ByteArrayOutputStream(1024); try { OutputStream os = baos; if (isCompressStateInSession(context)) { if (log.isTraceEnabled()) log.trace("Processing serializeView - serialize compressed"); os.write(COMPRESSED_FLAG); os = new GZIPOutputStream(os, 1024); } else { if (log.isTraceEnabled()) log.trace("Processing serializeView - serialize uncompressed"); os.write(UNCOMPRESSED_FLAG); } ObjectOutputStream out = new ObjectOutputStream(os); out.writeObject(serializedView.getStructure()); out.writeObject(serializedView.getState()); out.close(); baos.close(); if (log.isTraceEnabled()) log.trace("Exiting serializeView - serialized. Bytes : " + baos.size()); return baos.toByteArray(); } catch (IOException e) { log.error("Exiting serializeView - Could not serialize state: " + e.getMessage(), e); return null; } } else { if (log.isTraceEnabled()) log.trace("Exiting serializeView - do not serialize state in session."); return new Object[] { serializedView.getStructure(), serializedView.getState() }; } } /** * Reads the value of the <code>org.apache.myfaces.SERIALIZE_STATE_IN_SESSION</code> context parameter. * * @param context <code>FacesContext</code> for the request we are processing. * @return boolean true, if the server state should be serialized in the session * @see SERIALIZE_STATE_IN_SESSION_PARAM */ protected boolean isSerializeStateInSession(FacesContext context) { String value = context.getExternalContext().getInitParameter(SERIALIZE_STATE_IN_SESSION_PARAM); boolean serialize = DEFAULT_SERIALIZE_STATE_IN_SESSION; if (value != null) { serialize = new Boolean(value).booleanValue(); } return serialize; } /** * Reads the value of the <code>org.apache.myfaces.COMPRESS_STATE_IN_SESSION</code> context parameter. * * @param context <code>FacesContext</code> for the request we are processing. * @return boolean true, if the server state steam should be compressed * @see COMPRESS_SERVER_STATE_PARAM */ protected boolean isCompressStateInSession(FacesContext context) { String value = context.getExternalContext().getInitParameter(COMPRESS_SERVER_STATE_PARAM); boolean compress = DEFAULT_COMPRESS_SERVER_STATE_PARAM; if (value != null) { compress = new Boolean(value).booleanValue(); } return compress; } protected SerializedView deserializeView(Object state) { if (log.isTraceEnabled()) log.trace("Entering deserializeView"); if (state instanceof byte[]) { if (log.isTraceEnabled()) log.trace("Processing deserializeView - deserializing serialized state. Bytes : " + ((byte[]) state).length); try { ByteArrayInputStream bais = new ByteArrayInputStream((byte[]) state); InputStream is = bais; if (is.read() == COMPRESSED_FLAG) { is = new GZIPInputStream(is); } ObjectInputStream in = new MyFacesObjectInputStream(is); return new SerializedView(in.readObject(), in.readObject()); } catch (IOException e) { log.error("Exiting deserializeView - Could not deserialize state: " + e.getMessage(), e); return null; } catch (ClassNotFoundException e) { log.error("Exiting deserializeView - Could not deserialize state: " + e.getMessage(), e); return null; } } else if (state instanceof Object[]) { if (log.isTraceEnabled()) log.trace("Exiting deserializeView - state not serialized."); Object[] value = (Object[]) state; return new SerializedView(value[0], value[1]); } else if (state == null) { log.error("Exiting deserializeView - this method should not be called with a null-state."); return null; } else { log.error("Exiting deserializeView - this method should not be called with a state of type : " + state.getClass()); return null; } } protected static class SerializedViewCollection implements Serializable { private static final long serialVersionUID = -3734849062185115847L; private final List _keys = new ArrayList(DEFAULT_NUMBER_OF_VIEWS_IN_SESSION); private final Map _serializedViews = new HashMap(); // old views will be hold as soft references which will be removed by // the garbage collector if free memory is low private transient Map _oldSerializedViews = null; public synchronized void add(FacesContext context, Object state) { Object key = new SerializedViewKey(context); _serializedViews.put(key, state); while (_keys.remove(key)) ; _keys.add(key); int views = getNumberOfViewsInSession(context); while (_keys.size() > views) { key = _keys.remove(0); Object oldView = _serializedViews.remove(key); if (oldView != null) { getOldSerializedViewsMap().put(key, oldView); } } } /** * Reads the amount (default = 20) of views to be stored in session. * * @param context FacesContext for the current request, we are processing * @return Number vf views stored in the session * @see NUMBER_OF_VIEWS_IN_SESSION_PARAM */ protected int getNumberOfViewsInSession(FacesContext context) { String value = context.getExternalContext().getInitParameter(NUMBER_OF_VIEWS_IN_SESSION_PARAM); int views = DEFAULT_NUMBER_OF_VIEWS_IN_SESSION; if (value != null) { try { views = Integer.parseInt(value); if (views <= 0) { log.error("Configured value for " + NUMBER_OF_VIEWS_IN_SESSION_PARAM + " is not valid, must be an value > 0, using default value (" + DEFAULT_NUMBER_OF_VIEWS_IN_SESSION); views = DEFAULT_NUMBER_OF_VIEWS_IN_SESSION; } } catch (Throwable e) { log.error("Error determining the value for " + NUMBER_OF_VIEWS_IN_SESSION_PARAM + ", expected an integer value > 0, using default value (" + DEFAULT_NUMBER_OF_VIEWS_IN_SESSION + "): " + e.getMessage(), e); } } return views; } /** * @return old serialized views map */ protected Map getOldSerializedViewsMap() { if (_oldSerializedViews == null) { _oldSerializedViews = new ReferenceMap(); } return _oldSerializedViews; } public Object get(Integer sequence, String viewId) { Object key = new SerializedViewKey(viewId, sequence); Object value = _serializedViews.get(key); if (value == null) { value = getOldSerializedViewsMap().get(key); } return value; } } protected static class SerializedViewKey implements Serializable { private static final long serialVersionUID = -1170697124386063642L; private final String _viewId; private final Integer _sequenceId; public SerializedViewKey(String viewId, Integer sequence) { _sequenceId = sequence; _viewId = viewId; } public SerializedViewKey(FacesContext context) { _sequenceId = ViewSequenceUtils.getViewSequence(context); _viewId = context.getViewRoot().getViewId(); } public boolean equals(Object obj) { if (obj == null) { return false; } if (obj == this) { return true; } if (obj instanceof SerializedViewKey) { SerializedViewKey other = (SerializedViewKey) obj; return new EqualsBuilder().append(other._viewId, _viewId).append(other._sequenceId, _sequenceId) .isEquals(); } return false; } public int hashCode() { return new HashCodeBuilder().append(_viewId).append(_sequenceId).toHashCode(); } } }