fix some (old) quality flaws

server/sonar-webserver-webapi/src/main/java/org/sonar/server/metric/ws/SearchAction.java

@@ -89,13 +89,13 @@ public class SearchAction implements MetricsWsAction {
     try (DbSession dbSession = dbClient.openSession(false)) {
       List<MetricDto> metrics = dbClient.metricDao().selectEnabled(dbSession, isCustom, searchOptions.getOffset(), searchOptions.getLimit());
       int nbMetrics = dbClient.metricDao().countEnabled(dbSession, isCustom);
-      JsonWriter json = response.newJsonWriter();
-      json.beginObject();
-      Set<String> desiredFields = desiredFields(request.paramAsStrings(Param.FIELDS));
-      writeMetrics(json, metrics, desiredFields);
-      searchOptions.writeJson(json, nbMetrics);
-      json.endObject();
-      json.close();
+      try (JsonWriter json = response.newJsonWriter()) {
+        json.beginObject();
+        Set<String> desiredFields = desiredFields(request.paramAsStrings(Param.FIELDS));
+        writeMetrics(json, metrics, desiredFields);
+        searchOptions.writeJson(json, nbMetrics);
+        json.endObject();
+      }
     }
   }
 

server/sonar-webserver/src/main/java/org/sonar/server/platform/web/MasterServletFilter.java

@@ -25,6 +25,8 @@ import com.google.common.collect.Lists;
 import java.io.IOException;
 import java.util.Iterator;
 import java.util.List;
+import javax.annotation.CheckForNull;
+import javax.annotation.Nullable;
 import javax.servlet.Filter;
 import javax.servlet.FilterChain;
 import javax.servlet.FilterConfig;
@@ -41,7 +43,7 @@ import org.sonar.server.platform.PlatformImpl;
  */
 public class MasterServletFilter implements Filter {
 
-  public static volatile MasterServletFilter INSTANCE;
+  private static volatile MasterServletFilter INSTANCE;
   private ServletFilter[] filters;
   private FilterConfig config;
 
@@ -59,6 +61,16 @@ public class MasterServletFilter implements Filter {
     init(config, PlatformImpl.getInstance().getContainer().getComponentsByType(ServletFilter.class));
   }
 
+  @CheckForNull
+  public static MasterServletFilter getInstance() {
+    return INSTANCE;
+  }
+
+  @VisibleForTesting
+  static void setInstance(@Nullable MasterServletFilter instance) {
+    INSTANCE = instance;
+  }
+
   void init(FilterConfig config, List<ServletFilter> filters) {
     this.config = config;
     initFilters(filters);

server/sonar-webserver/src/main/java/org/sonar/server/platform/web/RegisterServletFilters.java

@@ -39,11 +39,12 @@ public class RegisterServletFilters implements Startable {
 
   @Override
   public void start() {
-    if (MasterServletFilter.INSTANCE != null) {
+    MasterServletFilter masterServletFilter = MasterServletFilter.getInstance();
+    if (masterServletFilter != null) {
       // Probably a database upgrade. MasterSlaveFilter was instantiated by the servlet container
       // while picocontainer was not completely up.
       // See https://jira.sonarsource.com/browse/SONAR-3612
-      MasterServletFilter.INSTANCE.initFilters(Arrays.asList(filters));
+      masterServletFilter.initFilters(Arrays.asList(filters));
     }
   }
 

server/sonar-webserver/src/test/java/org/sonar/server/platform/web/MasterServletFilterTest.java

@@ -56,7 +56,7 @@ public class MasterServletFilterTest {
 
   @Before
   public void resetSingleton() {
-    MasterServletFilter.INSTANCE = null;
+    MasterServletFilter.setInstance(null);
   }
 
   @Test

server/sonar-webserver/src/test/java/org/sonar/server/platform/web/RegisterServletFiltersTest.java

@@ -19,7 +19,6 @@
  */
 package org.sonar.server.platform.web;
 
-import javax.servlet.ServletException;
 import org.junit.Test;
 import org.sonar.api.web.ServletFilter;
 
@@ -29,24 +28,24 @@ import static org.mockito.Mockito.verify;
 
 public class RegisterServletFiltersTest {
   @Test
-  public void should_not_fail_if_master_filter_is_not_up() throws ServletException {
-    MasterServletFilter.INSTANCE = null;
+  public void should_not_fail_if_master_filter_is_not_up() {
+    MasterServletFilter.setInstance(null);
     new RegisterServletFilters(new ServletFilter[2]).start();
   }
 
   @Test
-  public void should_register_filters_if_master_filter_is_up() throws ServletException {
-    MasterServletFilter.INSTANCE = mock(MasterServletFilter.class);
+  public void should_register_filters_if_master_filter_is_up() {
+    MasterServletFilter.setInstance(mock(MasterServletFilter.class));
     new RegisterServletFilters(new ServletFilter[2]).start();
 
-    verify(MasterServletFilter.INSTANCE).initFilters(anyList());
+    verify(MasterServletFilter.getInstance()).initFilters(anyList());
   }
 
   @Test
-  public void filters_should_be_optional() throws ServletException {
-    MasterServletFilter.INSTANCE = mock(MasterServletFilter.class);
+  public void filters_should_be_optional() {
+    MasterServletFilter.setInstance(mock(MasterServletFilter.class));
     new RegisterServletFilters().start();
     // do not fail
-    verify(MasterServletFilter.INSTANCE).initFilters(anyList());
+    verify(MasterServletFilter.getInstance()).initFilters(anyList());
   }
 }