ItEr20S04ArquitecturaServidorItEr19S04: Adding automatic handling of OptimistLockingFailureException.

navalplanner-webapp/src/main/java/org/navalplanner/web/common/ConcurrentModificationController.java

@@ -0,0 +1,46 @@
+package org.navalplanner.web.common;
+
+import javax.servlet.http.HttpServletRequest;
+
+import org.apache.commons.logging.Log;
+import org.apache.commons.logging.LogFactory;
+import org.springframework.dao.OptimisticLockingFailureException;
+import org.zkoss.zk.ui.Component;
+import org.zkoss.zk.ui.Executions;
+import org.zkoss.zk.ui.util.GenericForwardComposer;
+
+public class ConcurrentModificationController extends GenericForwardComposer {
+
+    private static final Log LOG = LogFactory
+            .getLog(ConcurrentModificationController.class);
+    private String backURL;
+
+    @Override
+    public void doAfterCompose(Component comp) throws Exception {
+        super.doAfterCompose(comp);
+        backURL = getBackURL();
+    }
+
+    public static void showException(
+            OptimisticLockingFailureException exception, String backURL) {
+        LOG
+                .error(
+                        "an OptimistLockingFailureException caused a disruption to an user",
+                        exception);
+        Executions.sendRedirect("/common/concurrent_modification.zul?back="
+                + backURL);
+    }
+
+    private static String getBackURL() {
+        return getRequest().getParameter("back");
+    }
+
+    private static HttpServletRequest getRequest() {
+        return (HttpServletRequest) Executions.getCurrent().getNativeRequest();
+    }
+
+    public void onClick$continue() {
+        Executions.sendRedirect(backURL);
+    }
+
+}

navalplanner-webapp/src/main/java/org/navalplanner/web/common/ConcurrentModificationDetector.java

@@ -0,0 +1,28 @@
+package org.navalplanner.web.common;
+
+import org.navalplanner.web.common.ExceptionCatcherProxy.IExceptionHandler;
+import org.springframework.dao.OptimisticLockingFailureException;
+
+public class ConcurrentModificationDetector {
+
+    public static <T> T detectConcurrentModification(Class<T> interfaceClass,
+            T model, final String backURL) {
+        IExceptionHandler<OptimisticLockingFailureException> handler = createHandler(backURL);
+        return ExceptionCatcherProxy.doCatchFor(interfaceClass).when(
+                OptimisticLockingFailureException.class, handler)
+                .applyTo(model);
+    }
+
+    private static IExceptionHandler<OptimisticLockingFailureException> createHandler(
+            final String backURL) {
+        return new IExceptionHandler<OptimisticLockingFailureException>() {
+
+            @Override
+            public void onException(OptimisticLockingFailureException exception) {
+                ConcurrentModificationController.showException(exception,
+                        backURL);
+            }
+        };
+    }
+
+}

navalplanner-webapp/src/main/webapp/common/concurrent_modification.zul

@@ -0,0 +1,19 @@
+<?init class="org.zkoss.zk.ui.util.Composition" arg0="/common/layout/template_v02.zul"?>
+<?link rel="stylesheet" type="text/css" href="/common/css/navalpro_v01.css"?>
+<?link rel="stylesheet" type="text/css" href="/common/css/navalpro_zk.css"?>
+<zk>
+
+    <window self="@{define(content)}" >
+        <!--caption>
+            Erro ${requestScope['javax.servlet.error.status_code']}
+        </caption-->
+        <vbox apply="org.navalplanner.web.common.ConcurrentModificationController"
+            sclass="errorbox">
+            Another user has modified the same data, so the operation couldn't be completed.
+
+            <hbox style="margin-left:auto; margin-right:auto">
+                <button id="continue" label="Continue" />
+            </hbox>
+        </vbox>
+    </window>
+</zk>