Fix quality flaws

server/sonar-server/src/main/java/org/sonar/server/notification/email/EmailNotificationChannel.java

   @Override
   public void deliver(Notification notification, String username) {
     User user = userFinder.findByLogin(username);
-    if (StringUtils.isBlank(user.email())) {
-      LOG.debug("Email not defined for user: " + username);
+    if (user == null || StringUtils.isBlank(user.email())) {
+      LOG.debug("User does not exist or has no email: {}", username);
       return;
     }
     EmailMessage emailMessage = format(notification);

sonar-application/src/main/java/org/sonar/application/JdbcSettings.java

 import org.apache.commons.io.FileUtils;
 import org.apache.commons.lang.StringUtils;
 import org.slf4j.LoggerFactory;
+import org.sonar.api.utils.log.Loggers;
 import org.sonar.process.MessageException;
 import org.sonar.process.ProcessProperties;
 import org.sonar.process.Props;
 import java.util.regex.Matcher;
 import java.util.regex.Pattern;
 
+import static java.lang.String.format;
+
 public class JdbcSettings {
 
   enum Provider {
     Pattern pattern = Pattern.compile("jdbc:(\\w+):.+");
     Matcher matcher = pattern.matcher(url);
     if (!matcher.find()) {
-      throw new MessageException(String.format("Bad format of JDBC URL: " + url));
+      throw new MessageException(format("Bad format of JDBC URL: %s", url));
     }
     String key = matcher.group(1);
     try {
       return Provider.valueOf(StringUtils.upperCase(key));
     } catch (IllegalArgumentException e) {
-      throw new MessageException(String.format(String.format("Unsupported JDBC driver provider: %s", key)));
+      throw new MessageException(format("Unsupported JDBC driver provider: %s", key));
     }
   }
 
 
   private static void checkRequiredParameter(String url, String val) {
     if (!url.contains(val)) {
-      throw new MessageException(String.format("JDBC URL must have the property '%s'", val));
+      throw new MessageException(format("JDBC URL must have the property '%s'", val));
     }
   }
 
   private void checkRecommendedParameter(String url, String val) {
     if (!url.contains(val)) {
-      LoggerFactory.getLogger(getClass()).warn(String.format("JDBC URL is recommended to have the property '%s'", val));
+      Loggers.get(getClass()).warn("JDBC URL is recommended to have the property '{}'", val);
     }
   }
 }

sonar-core/src/main/java/org/sonar/core/notification/package-info.java

-/*
- * SonarQube, open source software quality management tool.
- * Copyright (C) 2008-2014 SonarSource
- * mailto:contact AT sonarsource DOT com
- *
- * SonarQube is free software; you can redistribute it and/or
- * modify it under the terms of the GNU Lesser General Public
- * License as published by the Free Software Foundation; either
- * version 3 of the License, or (at your option) any later version.
- *
- * SonarQube is distributed in the hope that it will be useful,
- * but WITHOUT ANY WARRANTY; without even the implied warranty of
- * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
- * Lesser General Public License for more details.
- *
- * You should have received a copy of the GNU Lesser General Public License
- * along with this program; if not, write to the Free Software Foundation,
- * Inc., 51 Franklin Street, Fifth Floor, Boston, MA  02110-1301, USA.
- */
-@ParametersAreNonnullByDefault
-package org.sonar.core.notification;
-
-import javax.annotation.ParametersAreNonnullByDefault;

sonar-core/src/main/java/org/sonar/core/qualityprofile/package-info.java

-/*
- * SonarQube, open source software quality management tool.
- * Copyright (C) 2008-2014 SonarSource
- * mailto:contact AT sonarsource DOT com
- *
- * SonarQube is free software; you can redistribute it and/or
- * modify it under the terms of the GNU Lesser General Public
- * License as published by the Free Software Foundation; either
- * version 3 of the License, or (at your option) any later version.
- *
- * SonarQube is distributed in the hope that it will be useful,
- * but WITHOUT ANY WARRANTY; without even the implied warranty of
- * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
- * Lesser General Public License for more details.
- *
- * You should have received a copy of the GNU Lesser General Public License
- * along with this program; if not, write to the Free Software Foundation,
- * Inc., 51 Franklin Street, Fifth Floor, Boston, MA  02110-1301, USA.
- */
-@ParametersAreNonnullByDefault
-package org.sonar.core.qualityprofile;
-
-import javax.annotation.ParametersAreNonnullByDefault;

sonar-home/src/main/java/org/sonar/home/cache/FileCache.java

     // Check if the file was cached by another process during download
     if (!rename && !targetFile.exists()) {
       log.warn(String.format("Unable to rename %s to %s", sourceFile.getAbsolutePath(), targetFile.getAbsolutePath()));
-      log.warn(String.format("A copy/delete will be tempted but with no garantee of atomicity"));
+      log.warn("A copy/delete will be tempted but with no guarantee of atomicity");
       try {
         Files.move(sourceFile.toPath(), targetFile.toPath());
       } catch (IOException e) {

sonar-plugin-api/src/main/java/org/sonar/api/utils/ZipUtils.java

   }
 
   public static File unzip(InputStream zip, File toDir) throws IOException {
-    unzip(zip, toDir, new ZipEntryFilter() {
-      @Override
-      public boolean accept(ZipEntry entry) {
-        return true;
-      }
-    });
+    unzip(zip, toDir, TrueZipEntryFilter.INSTANCE);
     return toDir;
   }
 
+  private enum TrueZipEntryFilter implements ZipEntryFilter {
+    INSTANCE;
+    @Override
+    public boolean accept(ZipEntry entry) {
+      return true;
+    }
+  }
+
   public static File unzip(InputStream stream, File toDir, ZipEntryFilter filter) throws IOException {
     if (!toDir.exists()) {
       FileUtils.forceMkdir(toDir);