Hypervisor as class (#8798)

* HypervisorType as a class

* Fixup

* fixup

* Add missing annotation

* Resolve comments

* Handle parallels typo

* Add missing @Convert annotation

api/src/main/java/com/cloud/hypervisor/Hypervisor.java

@@ -17,55 +17,45 @@
 package com.cloud.hypervisor;
 
 import com.cloud.storage.Storage.ImageFormat;
+import org.apache.commons.lang3.StringUtils;
 
-import java.util.HashMap;
+import java.util.LinkedHashMap;
 import java.util.Locale;
 import java.util.Map;
+import java.util.Objects;
 
 public class Hypervisor {
+    public static class HypervisorType {
+        private static final Map<String, HypervisorType> hypervisorTypeMap = new LinkedHashMap<>();
+        public static final HypervisorType None = new HypervisorType("None"); //for storage hosts
+        public static final HypervisorType XenServer = new HypervisorType("XenServer", ImageFormat.VHD);
+        public static final HypervisorType KVM = new HypervisorType("KVM", ImageFormat.QCOW2);
+        public static final HypervisorType VMware = new HypervisorType("VMware", ImageFormat.OVA);
+        public static final HypervisorType Hyperv = new HypervisorType("Hyperv");
+        public static final HypervisorType VirtualBox = new HypervisorType("VirtualBox");
+        public static final HypervisorType Parralels = new HypervisorType("Parralels");
+        public static final HypervisorType BareMetal = new HypervisorType("BareMetal");
+        public static final HypervisorType Simulator = new HypervisorType("Simulator");
+        public static final HypervisorType Ovm = new HypervisorType("Ovm", ImageFormat.RAW);
+        public static final HypervisorType Ovm3 = new HypervisorType("Ovm3", ImageFormat.RAW);
+        public static final HypervisorType LXC = new HypervisorType("LXC");
+        public static final HypervisorType Custom = new HypervisorType("Custom");
+        public static final HypervisorType Any = new HypervisorType("Any"); /*If you don't care about the hypervisor type*/
+        private final String name;
+        private final ImageFormat imageFormat;
 
-    static Map<String, HypervisorType> hypervisorTypeMap;
+        public HypervisorType(String name) {
-    static Map<HypervisorType, ImageFormat> supportedImageFormatMap;
+            this(name, null);
+        }
 
-    public enum HypervisorType {
+        public HypervisorType(String name, ImageFormat imageFormat) {
-        None, //for storage hosts
+            this.name = name;
-        XenServer,
+            this.imageFormat = imageFormat;
-        KVM,
+            if (name.equals("Parralels")){ // typo in the original code
-        VMware,
+                hypervisorTypeMap.put("parallels", this);
-        Hyperv,
+            } else {
-        VirtualBox,
+                hypervisorTypeMap.putIfAbsent(name.toLowerCase(Locale.ROOT), this);
-        Parralels,
+            }
-        BareMetal,
-        Simulator,
-        Ovm,
-        Ovm3,
-        LXC,
-        Custom,
-
-        Any; /*If you don't care about the hypervisor type*/
-
-        static {
-            hypervisorTypeMap = new HashMap<>();
-            hypervisorTypeMap.put("xenserver", HypervisorType.XenServer);
-            hypervisorTypeMap.put("kvm", HypervisorType.KVM);
-            hypervisorTypeMap.put("vmware", HypervisorType.VMware);
-            hypervisorTypeMap.put("hyperv", HypervisorType.Hyperv);
-            hypervisorTypeMap.put("virtualbox", HypervisorType.VirtualBox);
-            hypervisorTypeMap.put("parallels", HypervisorType.Parralels);
-            hypervisorTypeMap.put("baremetal", HypervisorType.BareMetal);
-            hypervisorTypeMap.put("simulator", HypervisorType.Simulator);
-            hypervisorTypeMap.put("ovm", HypervisorType.Ovm);
-            hypervisorTypeMap.put("lxc", HypervisorType.LXC);
-            hypervisorTypeMap.put("any", HypervisorType.Any);
-            hypervisorTypeMap.put("ovm3", HypervisorType.Ovm3);
-            hypervisorTypeMap.put("custom", HypervisorType.Custom);
-
-            supportedImageFormatMap = new HashMap<>();
-            supportedImageFormatMap.put(HypervisorType.XenServer, ImageFormat.VHD);
-            supportedImageFormatMap.put(HypervisorType.KVM, ImageFormat.QCOW2);
-            supportedImageFormatMap.put(HypervisorType.VMware, ImageFormat.OVA);
-            supportedImageFormatMap.put(HypervisorType.Ovm, ImageFormat.RAW);
-            supportedImageFormatMap.put(HypervisorType.Ovm3, ImageFormat.RAW);
         }
 
         public static HypervisorType getType(String hypervisor) {
@@ -75,24 +65,62 @@ public class Hypervisor {
                             hypervisorTypeMap.getOrDefault(hypervisor.toLowerCase(Locale.ROOT), HypervisorType.None));
         }
 
+        public static HypervisorType[] values() {
+            return hypervisorTypeMap.values().toArray(HypervisorType[]::new).clone();
+        }
+
+        public static HypervisorType valueOf(String name) {
+            if (StringUtils.isBlank(name)) {
+                return null;
+            }
+
+            HypervisorType hypervisorType = hypervisorTypeMap.get(name.toLowerCase(Locale.ROOT));
+            if (hypervisorType == null) {
+                throw new IllegalArgumentException("HypervisorType '" + name + "' not found");
+            }
+            return hypervisorType;
+        }
+
         /**
          * Returns the display name of a hypervisor type in case the custom hypervisor is used,
          * using the 'hypervisor.custom.display.name' setting. Otherwise, returns hypervisor name
          */
         public String getHypervisorDisplayName() {
-            return !Hypervisor.HypervisorType.Custom.equals(this) ?
+            return HypervisorType.Custom.equals(this) ? HypervisorGuru.HypervisorCustomDisplayName.value() : name;
-                    this.toString() :
-                    HypervisorGuru.HypervisorCustomDisplayName.value();
         }
 
         /**
          * This method really needs to be part of the properties of the hypervisor type itself.
          *
-         * @param hyperType
          * @return
          */
-        public static ImageFormat getSupportedImageFormat(HypervisorType hyperType) {
+        public ImageFormat getSupportedImageFormat() {
-            return supportedImageFormatMap.getOrDefault(hyperType, null);
+            return imageFormat;
+        }
+
+        public String name() {
+            return name;
+        }
+
+        @Override
+        public int hashCode() {
+            return Objects.hash(name);
+        }
+
+        @Override
+        public boolean equals(Object o) {
+            if (o == this) {
+                return true;
+            } else if (o == null || getClass() != o.getClass()) {
+                return false;
+            }
+            HypervisorType that = (HypervisorType) o;
+            return Objects.equals(name, that.name);
+        }
+
+        @Override
+        public String toString() {
+            return name;
         }
     }
 

core/src/main/java/com/cloud/serializer/GsonHelper.java

@@ -21,6 +21,8 @@ package com.cloud.serializer;
 
 import java.util.List;
 
+import com.cloud.hypervisor.Hypervisor;
+import org.apache.cloudstack.transport.HypervisorTypeAdaptor;
 import org.apache.logging.log4j.Logger;
 import org.apache.logging.log4j.LogManager;
 
@@ -75,6 +77,7 @@ public class GsonHelper {
         builder.registerTypeAdapter(new TypeToken<Pair<Long, Long>>() {
         }.getType(), new NwGroupsCommandTypeAdaptor());
         builder.registerTypeAdapter(Storage.StoragePoolType.class, new StoragePoolTypeAdaptor());
+        builder.registerTypeAdapter(Hypervisor.HypervisorType.class, new HypervisorTypeAdaptor());
         Gson gson = builder.create();
         dsAdaptor.initGson(gson);
         dtAdaptor.initGson(gson);

core/src/main/java/org/apache/cloudstack/transport/HypervisorTypeAdaptor.java

@@ -0,0 +1,53 @@
+// 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.cloudstack.transport;
+
+import com.cloud.hypervisor.Hypervisor.HypervisorType;
+import com.google.gson.JsonDeserializationContext;
+import com.google.gson.JsonDeserializer;
+import com.google.gson.JsonElement;
+import com.google.gson.JsonNull;
+import com.google.gson.JsonParseException;
+import com.google.gson.JsonPrimitive;
+import com.google.gson.JsonSerializationContext;
+import com.google.gson.JsonSerializer;
+
+import java.lang.reflect.Type;
+
+/**
+ * {@link HypervisorType} acts as extendable set of singleton objects and should return same result when used "=="
+ * or {@link Object#equals(Object)}.
+ * To support that, need to return existing object for a given name instead of creating new.
+ */
+public class HypervisorTypeAdaptor implements JsonDeserializer<HypervisorType>, JsonSerializer<HypervisorType> {
+    @Override
+    public HypervisorType deserialize(JsonElement json, Type typeOfT, JsonDeserializationContext context) throws JsonParseException {
+        if (json instanceof JsonPrimitive && ((JsonPrimitive) json).isString()) {
+            return HypervisorType.valueOf(json.getAsString());
+        }
+        return null;
+    }
+
+    @Override
+    public JsonElement serialize(HypervisorType src, Type typeOfSrc, JsonSerializationContext context) {
+        String name = src.name();
+        if (name == null) {
+            return new JsonNull();
+        }
+        return new JsonPrimitive(name);
+    }
+}

engine/orchestration/src/main/java/com/cloud/vm/VirtualMachineManagerImpl.java

@@ -1735,17 +1735,12 @@ public class VirtualMachineManagerImpl extends ManagerBase implements VirtualMac
             return ExecuteInSequence.value();
         }
 
-        switch (hypervisorType) {
+        if (Set.of(HypervisorType.KVM, HypervisorType.XenServer, HypervisorType.Hyperv, HypervisorType.LXC).contains(hypervisorType)) {
-            case KVM:
+            return false;
-            case XenServer:
+        } else if (hypervisorType.equals(HypervisorType.VMware)) {
-            case Hyperv:
+            return StorageManager.shouldExecuteInSequenceOnVmware();
-            case LXC:
-                return false;
-            case VMware:
-                return StorageManager.shouldExecuteInSequenceOnVmware();
-            default:
-                return ExecuteInSequence.value();
         }
+        return ExecuteInSequence.value();
     }
 
     @Override

engine/orchestration/src/main/java/org/apache/cloudstack/engine/datacenter/entity/api/db/EngineClusterVO.java

@@ -26,8 +26,10 @@ import com.cloud.utils.db.StateMachine;
 import org.apache.cloudstack.api.Identity;
 import org.apache.cloudstack.engine.datacenter.entity.api.DataCenterResourceEntity.State;
 import org.apache.cloudstack.engine.datacenter.entity.api.DataCenterResourceEntity.State.Event;
+import org.apache.cloudstack.util.HypervisorTypeConverter;
 
 import javax.persistence.Column;
+import javax.persistence.Convert;
 import javax.persistence.Entity;
 import javax.persistence.EnumType;
 import javax.persistence.Enumerated;
@@ -62,6 +64,7 @@ public class EngineClusterVO implements EngineCluster, Identity {
     long podId;
 
     @Column(name = "hypervisor_type")
+    @Convert(converter = HypervisorTypeConverter.class)
     String hypervisorType;
 
     @Column(name = "cluster_type")

engine/orchestration/src/main/java/org/apache/cloudstack/engine/datacenter/entity/api/db/EngineHostVO.java

@@ -50,6 +50,7 @@ import com.cloud.util.StoragePoolTypeConverter;
 import com.cloud.utils.NumbersUtil;
 import com.cloud.utils.db.GenericDao;
 import com.cloud.utils.db.StateMachine;
+import org.apache.cloudstack.util.HypervisorTypeConverter;
 
 @Entity
 @Table(name = "host")
@@ -118,7 +119,7 @@ public class EngineHostVO implements EngineHost, Identity {
     private String storageMacAddressDeux;
 
     @Column(name = "hypervisor_type", updatable = true, nullable = false)
-    @Enumerated(value = EnumType.STRING)
+    @Convert(converter = HypervisorTypeConverter.class)
     private HypervisorType hypervisorType;
 
     @Column(name = "proxy_port")

engine/schema/src/main/java/com/cloud/dc/ClusterVO.java

@@ -22,8 +22,10 @@ import com.cloud.org.Grouping;
 import com.cloud.org.Managed.ManagedState;
 import com.cloud.utils.NumbersUtil;
 import com.cloud.utils.db.GenericDao;
+import org.apache.cloudstack.util.HypervisorTypeConverter;
 
 import javax.persistence.Column;
+import javax.persistence.Convert;
 import javax.persistence.Entity;
 import javax.persistence.EnumType;
 import javax.persistence.Enumerated;
@@ -56,6 +58,7 @@ public class ClusterVO implements Cluster {
     long podId;
 
     @Column(name = "hypervisor_type")
+    @Convert(converter = HypervisorTypeConverter.class)
     String hypervisorType;
 
     @Column(name = "cluster_type")

engine/schema/src/main/java/com/cloud/host/HostVO.java

@@ -42,6 +42,7 @@ import javax.persistence.Temporal;
 import javax.persistence.TemporalType;
 import javax.persistence.Transient;
 
+import org.apache.cloudstack.util.HypervisorTypeConverter;
 import org.apache.cloudstack.utils.jsinterpreter.TagAsRuleHelper;
 import org.apache.cloudstack.utils.reflectiontostringbuilderutils.ReflectionToStringBuilderUtils;
 import org.apache.commons.lang.BooleanUtils;
@@ -125,7 +126,7 @@ public class HostVO implements Host {
     private String storageMacAddressDeux;
 
     @Column(name = "hypervisor_type", updatable = true, nullable = false)
-    @Enumerated(value = EnumType.STRING)
+    @Convert(converter = HypervisorTypeConverter.class)
     private HypervisorType hypervisorType;
 
     @Column(name = "proxy_port")

engine/schema/src/main/java/com/cloud/hypervisor/HypervisorCapabilitiesVO.java

@@ -19,9 +19,8 @@ package com.cloud.hypervisor;
 import java.util.UUID;
 
 import javax.persistence.Column;
+import javax.persistence.Convert;
 import javax.persistence.Entity;
-import javax.persistence.EnumType;
-import javax.persistence.Enumerated;
 import javax.persistence.GeneratedValue;
 import javax.persistence.GenerationType;
 import javax.persistence.Id;
@@ -29,6 +28,7 @@ import javax.persistence.Table;
 
 import com.cloud.hypervisor.Hypervisor.HypervisorType;
 import com.cloud.utils.NumbersUtil;
+import org.apache.cloudstack.util.HypervisorTypeConverter;
 
 @Entity
 @Table(name = "hypervisor_capabilities")
@@ -39,7 +39,7 @@ public class HypervisorCapabilitiesVO implements HypervisorCapabilities {
     private long id;
 
     @Column(name = "hypervisor_type")
-    @Enumerated(value = EnumType.STRING)
+    @Convert(converter = HypervisorTypeConverter.class)
     private HypervisorType hypervisorType;
 
     @Column(name = "hypervisor_version")

engine/schema/src/main/java/com/cloud/storage/GuestOSHypervisorVO.java

@@ -20,6 +20,7 @@ import java.util.Date;
 import java.util.UUID;
 
 import javax.persistence.Column;
+import javax.persistence.Convert;
 import javax.persistence.Entity;
 import javax.persistence.GeneratedValue;
 import javax.persistence.GenerationType;
@@ -28,6 +29,7 @@ import javax.persistence.Table;
 
 import com.cloud.hypervisor.Hypervisor;
 import com.cloud.utils.db.GenericDao;
+import org.apache.cloudstack.util.HypervisorTypeConverter;
 
 @Entity
 @Table(name = "guest_os_hypervisor")
@@ -44,6 +46,7 @@ public class GuestOSHypervisorVO implements GuestOSHypervisor {
     String guestOsName;
 
     @Column(name = "hypervisor_type")
+    @Convert(converter = HypervisorTypeConverter.class)
     String hypervisorType;
 
     @Column(name = "hypervisor_version")

engine/schema/src/main/java/com/cloud/storage/SnapshotVO.java

@@ -20,6 +20,7 @@ import java.util.Date;
 import java.util.UUID;
 
 import javax.persistence.Column;
+import javax.persistence.Convert;
 import javax.persistence.Entity;
 import javax.persistence.EnumType;
 import javax.persistence.Enumerated;
@@ -28,6 +29,7 @@ import javax.persistence.GenerationType;
 import javax.persistence.Id;
 import javax.persistence.Table;
 
+import org.apache.cloudstack.util.HypervisorTypeConverter;
 import org.apache.commons.lang3.builder.ToStringBuilder;
 import org.apache.commons.lang3.builder.ToStringStyle;
 
@@ -89,7 +91,7 @@ public class SnapshotVO implements Snapshot {
     Date removed;
 
     @Column(name = "hypervisor_type")
-    @Enumerated(value = EnumType.STRING)
+    @Convert(converter = HypervisorTypeConverter.class)
     HypervisorType hypervisorType;
 
     @Expose

engine/schema/src/main/java/com/cloud/storage/VMTemplateVO.java

@@ -21,6 +21,7 @@ import java.util.Map;
 import java.util.UUID;
 
 import javax.persistence.Column;
+import javax.persistence.Convert;
 import javax.persistence.Entity;
 import javax.persistence.EnumType;
 import javax.persistence.Enumerated;
@@ -32,6 +33,7 @@ import javax.persistence.TemporalType;
 import javax.persistence.Transient;
 
 import com.cloud.user.UserData;
+import org.apache.cloudstack.util.HypervisorTypeConverter;
 import org.apache.cloudstack.utils.reflectiontostringbuilderutils.ReflectionToStringBuilderUtils;
 
 import com.cloud.hypervisor.Hypervisor.HypervisorType;
@@ -108,7 +110,7 @@ public class VMTemplateVO implements VirtualMachineTemplate {
     private boolean crossZones = false;
 
     @Column(name = "hypervisor_type")
-    @Enumerated(value = EnumType.STRING)
+    @Convert(converter = HypervisorTypeConverter.class)
     private HypervisorType hypervisorType;
 
     @Column(name = "extractable")

engine/schema/src/main/java/com/cloud/upgrade/SystemVmTemplateRegistration.java

@@ -446,7 +446,7 @@ public class SystemVmTemplateRegistration {
     private List<String> fetchAllHypervisors(Long zoneId) {
         List<String> hypervisorList = new ArrayList<>();
         List<Hypervisor.HypervisorType> hypervisorTypes = clusterDao.getAvailableHypervisorInZone(zoneId);
-        hypervisorList = hypervisorTypes.stream().distinct().map(Enum::name).collect(Collectors.toList());
+        hypervisorList = hypervisorTypes.stream().distinct().map(Hypervisor.HypervisorType::name).collect(Collectors.toList());
         return hypervisorList;
     }
 
@@ -719,8 +719,8 @@ public class SystemVmTemplateRegistration {
     }
 
     private void validateTemplates(Set<Hypervisor.HypervisorType> hypervisorsInUse) {
-        Set<String> hypervisors = hypervisorsInUse.stream().map(Enum::name).
+        Set<String> hypervisors = hypervisorsInUse.stream().
-                map(name -> name.toLowerCase(Locale.ROOT)).map(this::getHypervisorName).collect(Collectors.toSet());
+                map(Hypervisor.HypervisorType::name).map(name -> name.toLowerCase(Locale.ROOT)).map(this::getHypervisorName).collect(Collectors.toSet());
         List<String> templates = new ArrayList<>();
         for (Hypervisor.HypervisorType hypervisorType : hypervisorsInUse) {
             templates.add(FileNames.get(hypervisorType));

engine/schema/src/main/java/com/cloud/upgrade/dao/Upgrade41500to41510.java

@@ -31,6 +31,13 @@ import java.util.Set;
 import com.cloud.hypervisor.Hypervisor;
 import com.cloud.utils.exception.CloudRuntimeException;
 
+import static com.cloud.hypervisor.Hypervisor.HypervisorType.Hyperv;
+import static com.cloud.hypervisor.Hypervisor.HypervisorType.KVM;
+import static com.cloud.hypervisor.Hypervisor.HypervisorType.LXC;
+import static com.cloud.hypervisor.Hypervisor.HypervisorType.Ovm3;
+import static com.cloud.hypervisor.Hypervisor.HypervisorType.VMware;
+import static com.cloud.hypervisor.Hypervisor.HypervisorType.XenServer;
+
 public class Upgrade41500to41510 extends DbUpgradeAbstractImpl implements DbUpgradeSystemVmTemplate {
 
     @Override
@@ -71,27 +78,19 @@ public class Upgrade41500to41510 extends DbUpgradeAbstractImpl implements DbUpgr
         final Set<Hypervisor.HypervisorType> hypervisorsListInUse = new HashSet<Hypervisor.HypervisorType>();
         try (PreparedStatement pstmt = conn.prepareStatement("select distinct(hypervisor_type) from `cloud`.`cluster` where removed is null"); ResultSet rs = pstmt.executeQuery()) {
             while (rs.next()) {
-                switch (Hypervisor.HypervisorType.getType(rs.getString(1))) {
+                Hypervisor.HypervisorType type = Hypervisor.HypervisorType.getType(rs.getString(1));
-                    case XenServer:
+                if (type.equals(XenServer)) {
-                        hypervisorsListInUse.add(Hypervisor.HypervisorType.XenServer);
+                    hypervisorsListInUse.add(XenServer);
-                        break;
+                } else if (type.equals(KVM)) {
-                    case KVM:
+                    hypervisorsListInUse.add(KVM);
-                        hypervisorsListInUse.add(Hypervisor.HypervisorType.KVM);
+                } else if (type.equals(VMware)) {
-                        break;
+                    hypervisorsListInUse.add(VMware);
-                    case VMware:
+                } else if (type.equals(Hyperv)) {
-                        hypervisorsListInUse.add(Hypervisor.HypervisorType.VMware);
+                    hypervisorsListInUse.add(Hyperv);
-                        break;
+                } else if (type.equals(LXC)) {
-                    case Hyperv:
+                    hypervisorsListInUse.add(LXC);
-                        hypervisorsListInUse.add(Hypervisor.HypervisorType.Hyperv);
+                } else if (type.equals(Ovm3)) {
-                        break;
+                    hypervisorsListInUse.add(Ovm3);
-                    case LXC:
-                        hypervisorsListInUse.add(Hypervisor.HypervisorType.LXC);
-                        break;
-                    case Ovm3:
-                        hypervisorsListInUse.add(Hypervisor.HypervisorType.Ovm3);
-                        break;
-                    default:
-                        break;
                 }
             }
         } catch (final SQLException e) {
@@ -101,45 +100,45 @@ public class Upgrade41500to41510 extends DbUpgradeAbstractImpl implements DbUpgr
 
         final Map<Hypervisor.HypervisorType, String> NewTemplateNameList = new HashMap<Hypervisor.HypervisorType, String>() {
             {
-                put(Hypervisor.HypervisorType.KVM, "systemvm-kvm-4.15.1");
+                put(KVM, "systemvm-kvm-4.15.1");
-                put(Hypervisor.HypervisorType.VMware, "systemvm-vmware-4.15.1");
+                put(VMware, "systemvm-vmware-4.15.1");
-                put(Hypervisor.HypervisorType.XenServer, "systemvm-xenserver-4.15.1");
+                put(XenServer, "systemvm-xenserver-4.15.1");
-                put(Hypervisor.HypervisorType.Hyperv, "systemvm-hyperv-4.15.1");
+                put(Hyperv, "systemvm-hyperv-4.15.1");
-                put(Hypervisor.HypervisorType.LXC, "systemvm-lxc-4.15.1");
+                put(LXC, "systemvm-lxc-4.15.1");
-                put(Hypervisor.HypervisorType.Ovm3, "systemvm-ovm3-4.15.1");
+                put(Ovm3, "systemvm-ovm3-4.15.1");
             }
         };
 
         final Map<Hypervisor.HypervisorType, String> routerTemplateConfigurationNames = new HashMap<Hypervisor.HypervisorType, String>() {
             {
-                put(Hypervisor.HypervisorType.KVM, "router.template.kvm");
+                put(KVM, "router.template.kvm");
-                put(Hypervisor.HypervisorType.VMware, "router.template.vmware");
+                put(VMware, "router.template.vmware");
-                put(Hypervisor.HypervisorType.XenServer, "router.template.xenserver");
+                put(XenServer, "router.template.xenserver");
-                put(Hypervisor.HypervisorType.Hyperv, "router.template.hyperv");
+                put(Hyperv, "router.template.hyperv");
-                put(Hypervisor.HypervisorType.LXC, "router.template.lxc");
+                put(LXC, "router.template.lxc");
-                put(Hypervisor.HypervisorType.Ovm3, "router.template.ovm3");
+                put(Ovm3, "router.template.ovm3");
             }
         };
 
         final Map<Hypervisor.HypervisorType, String> newTemplateUrl = new HashMap<Hypervisor.HypervisorType, String>() {
             {
-                put(Hypervisor.HypervisorType.KVM, "https://download.cloudstack.org/systemvm/4.15/systemvmtemplate-4.15.1-kvm.qcow2.bz2");
+                put(KVM, "https://download.cloudstack.org/systemvm/4.15/systemvmtemplate-4.15.1-kvm.qcow2.bz2");
-                put(Hypervisor.HypervisorType.VMware, "https://download.cloudstack.org/systemvm/4.15/systemvmtemplate-4.15.1-vmware.ova");
+                put(VMware, "https://download.cloudstack.org/systemvm/4.15/systemvmtemplate-4.15.1-vmware.ova");
-                put(Hypervisor.HypervisorType.XenServer, "https://download.cloudstack.org/systemvm/4.15/systemvmtemplate-4.15.1-xen.vhd.bz2");
+                put(XenServer, "https://download.cloudstack.org/systemvm/4.15/systemvmtemplate-4.15.1-xen.vhd.bz2");
-                put(Hypervisor.HypervisorType.Hyperv, "https://download.cloudstack.org/systemvm/4.15/systemvmtemplate-4.15.1-hyperv.vhd.zip");
+                put(Hyperv, "https://download.cloudstack.org/systemvm/4.15/systemvmtemplate-4.15.1-hyperv.vhd.zip");
-                put(Hypervisor.HypervisorType.LXC, "https://download.cloudstack.org/systemvm/4.15/systemvmtemplate-4.15.1-kvm.qcow2.bz2");
+                put(LXC, "https://download.cloudstack.org/systemvm/4.15/systemvmtemplate-4.15.1-kvm.qcow2.bz2");
-                put(Hypervisor.HypervisorType.Ovm3, "https://download.cloudstack.org/systemvm/4.15/systemvmtemplate-4.15.1-ovm.raw.bz2");
+                put(Ovm3, "https://download.cloudstack.org/systemvm/4.15/systemvmtemplate-4.15.1-ovm.raw.bz2");
             }
         };
 
         final Map<Hypervisor.HypervisorType, String> newTemplateChecksum = new HashMap<Hypervisor.HypervisorType, String>() {
             {
-                put(Hypervisor.HypervisorType.KVM, "0e9f9a7d0957c3e0a2088e41b2da2cec");
+                put(KVM, "0e9f9a7d0957c3e0a2088e41b2da2cec");
-                put(Hypervisor.HypervisorType.XenServer, "86373992740b1eca8aff8b08ebf3aea5");
+                put(XenServer, "86373992740b1eca8aff8b08ebf3aea5");
-                put(Hypervisor.HypervisorType.VMware, "4006982765846d373eb3719b2fe4d720");
+                put(VMware, "4006982765846d373eb3719b2fe4d720");
-                put(Hypervisor.HypervisorType.Hyperv, "0b9514e4b6cba1f636fea2125f0f7a5f");
+                put(Hyperv, "0b9514e4b6cba1f636fea2125f0f7a5f");
-                put(Hypervisor.HypervisorType.LXC, "0e9f9a7d0957c3e0a2088e41b2da2cec");
+                put(LXC, "0e9f9a7d0957c3e0a2088e41b2da2cec");
-                put(Hypervisor.HypervisorType.Ovm3, "ae3977e696b3e6c81bdcbb792d514d29");
+                put(Ovm3, "ae3977e696b3e6c81bdcbb792d514d29");
             }
         };
 

engine/schema/src/main/java/com/cloud/vm/VMInstanceVO.java

@@ -26,6 +26,7 @@ import java.util.Map;
 import java.util.UUID;
 
 import javax.persistence.Column;
+import javax.persistence.Convert;
 import javax.persistence.DiscriminatorColumn;
 import javax.persistence.DiscriminatorType;
 import javax.persistence.Entity;
@@ -41,6 +42,7 @@ import javax.persistence.TemporalType;
 import javax.persistence.Transient;
 
 import org.apache.cloudstack.backup.Backup;
+import org.apache.cloudstack.util.HypervisorTypeConverter;
 import org.apache.cloudstack.utils.reflectiontostringbuilderutils.ReflectionToStringBuilderUtils;
 import org.apache.commons.codec.binary.Base64;
 import org.apache.logging.log4j.Logger;
@@ -159,7 +161,7 @@ public class VMInstanceVO implements VirtualMachine, FiniteStateObject<State, Vi
     protected String reservationId;
 
     @Column(name = "hypervisor_type")
-    @Enumerated(value = EnumType.STRING)
+    @Convert(converter = HypervisorTypeConverter.class)
     protected HypervisorType hypervisorType;
 
     @Column(name = "dynamically_scalable")

engine/schema/src/main/java/org/apache/cloudstack/direct/download/DirectDownloadCertificateVO.java

@@ -17,8 +17,10 @@
 package org.apache.cloudstack.direct.download;
 
 import com.cloud.hypervisor.Hypervisor;
+import org.apache.cloudstack.util.HypervisorTypeConverter;
 
 import javax.persistence.Column;
+import javax.persistence.Convert;
 import javax.persistence.Entity;
 import javax.persistence.GeneratedValue;
 import javax.persistence.GenerationType;
@@ -45,6 +47,7 @@ public class DirectDownloadCertificateVO implements DirectDownloadCertificate {
     private String certificate;
 
     @Column(name = "hypervisor_type")
+    @Convert(converter = HypervisorTypeConverter.class)
     private Hypervisor.HypervisorType hypervisorType;
 
     @Column(name = "zone_id")

engine/schema/src/main/java/org/apache/cloudstack/engine/cloud/entity/api/db/VMEntityVO.java

@@ -24,6 +24,7 @@ import java.util.Map;
 import java.util.UUID;
 
 import javax.persistence.Column;
+import javax.persistence.Convert;
 import javax.persistence.DiscriminatorColumn;
 import javax.persistence.DiscriminatorType;
 import javax.persistence.Entity;
@@ -48,6 +49,7 @@ import com.cloud.utils.fsm.FiniteStateObject;
 import com.cloud.vm.VirtualMachine;
 import com.cloud.vm.VirtualMachine.State;
 import com.google.gson.Gson;
+import org.apache.cloudstack.util.HypervisorTypeConverter;
 
 @Entity
 @Table(name = "vm_instance")
@@ -146,7 +148,7 @@ public class VMEntityVO implements VirtualMachine, FiniteStateObject<State, Virt
     protected String reservationId;
 
     @Column(name = "hypervisor_type")
-    @Enumerated(value = EnumType.STRING)
+    @Convert(converter = HypervisorTypeConverter.class)
     protected HypervisorType hypervisorType;
 
     @Transient

engine/schema/src/main/java/org/apache/cloudstack/storage/datastore/db/StoragePoolVO.java

@@ -25,6 +25,7 @@ import com.cloud.util.StoragePoolTypeConverter;
 import com.cloud.utils.UriUtils;
 import com.cloud.utils.db.Encrypt;
 import com.cloud.utils.db.GenericDao;
+import org.apache.cloudstack.util.HypervisorTypeConverter;
 
 import javax.persistence.Column;
 import javax.persistence.Convert;
@@ -118,7 +119,7 @@ public class StoragePoolVO implements StoragePool {
     private Long capacityIops;
 
     @Column(name = "hypervisor")
-    @Enumerated(value = EnumType.STRING)
+    @Convert(converter = HypervisorTypeConverter.class)
     private HypervisorType hypervisor;
 
     @Column(name = "parent")

engine/schema/src/main/java/org/apache/cloudstack/util/HypervisorTypeConverter.java

@@ -0,0 +1,38 @@
+// 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
+// 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.cloudstack.util;
+
+import com.cloud.hypervisor.Hypervisor;
+
+import javax.persistence.AttributeConverter;
+import javax.persistence.Converter;
+
+/**
+ * Converts {@link com.cloud.hypervisor.Hypervisor.HypervisorType} to and from {@link String} using {@link com.cloud.hypervisor.Hypervisor.HypervisorType#name()}.
+ */
+@Converter
+public class HypervisorTypeConverter implements AttributeConverter<Hypervisor.HypervisorType, String> {
+    @Override
+    public String convertToDatabaseColumn(Hypervisor.HypervisorType attribute) {
+        return attribute != null ? attribute.name() : null;
+    }
+
+    @Override
+    public Hypervisor.HypervisorType convertToEntityAttribute(String dbData) {
+        return dbData != null ? Hypervisor.HypervisorType.valueOf(dbData) : null;
+    }
+}

framework/db/src/main/java/com/cloud/utils/db/GenericDaoBase.java

@@ -1636,8 +1636,12 @@ public abstract class GenericDaoBase<T, ID extends Serializable> extends Compone
         } else if (attr.getValue() != null && attr.getValue() instanceof Long) {
             pstmt.setLong(j, (Long)attr.getValue());
         } else if(attr.field.getDeclaredAnnotation(Convert.class) != null) {
-            Object val = _conversionSupport.convertToDatabaseColumn(attr.field, value);
+            if (value instanceof String) {
-            pstmt.setObject(j, val);
+                pstmt.setString(j, (String)value);
+            } else {
+                Object val = _conversionSupport.convertToDatabaseColumn(attr.field, value);
+                pstmt.setObject(j, val);
+            }
         } else if (attr.field.getType() == String.class) {
             final String str;
             try {

plugins/network-elements/internal-loadbalancer/src/main/java/org/apache/cloudstack/network/lb/InternalLoadBalancerVMManagerImpl.java

@@ -118,6 +118,12 @@ import com.cloud.vm.VirtualMachineProfile.Param;
 import com.cloud.vm.dao.DomainRouterDao;
 import com.cloud.vm.dao.NicDao;
 
+import static com.cloud.hypervisor.Hypervisor.HypervisorType.Hyperv;
+import static com.cloud.hypervisor.Hypervisor.HypervisorType.KVM;
+import static com.cloud.hypervisor.Hypervisor.HypervisorType.LXC;
+import static com.cloud.hypervisor.Hypervisor.HypervisorType.VMware;
+import static com.cloud.hypervisor.Hypervisor.HypervisorType.XenServer;
+
 public class InternalLoadBalancerVMManagerImpl extends ManagerBase implements InternalLoadBalancerVMManager, InternalLoadBalancerVMService, VirtualMachineGuru {
     static final private String InternalLbVmNamePrefix = "b";
 
@@ -202,7 +208,7 @@ public class InternalLoadBalancerVMManagerImpl extends ManagerBase implements In
             } else if (nic.getTrafficType() == TrafficType.Control) {
                 controlNic = nic;
                 // Internal LB control command is sent over management server in VMware
-                if (dest.getHost().getHypervisorType() == HypervisorType.VMware) {
+                if (dest.getHost().getHypervisorType() == VMware) {
                     if (logger.isInfoEnabled()) {
                         logger.info("Check if we need to add management server explicit route to Internal LB. pod cidr: " + dest.getPod().getCidrAddress() + "/" +
                                 dest.getPod().getCidrSize() + ", pod gateway: " + dest.getPod().getGateway() + ", management host: " + _mgmtHost);
@@ -748,24 +754,16 @@ public class InternalLoadBalancerVMManagerImpl extends ManagerBase implements In
                     logger.debug("Creating the internal lb vm " + id + " in datacenter " + dest.getDataCenter() + " with hypervisor type " + hType);
                 }
                 String templateName = null;
-                switch (hType) {
+                if (hType.equals(XenServer)) {
-                case XenServer:
                     templateName = VirtualNetworkApplianceManager.RouterTemplateXen.valueIn(dest.getDataCenter().getId());
-                    break;
+                } else if (hType.equals(KVM)) {
-                case KVM:
                     templateName = VirtualNetworkApplianceManager.RouterTemplateKvm.valueIn(dest.getDataCenter().getId());
-                    break;
+                } else if (hType.equals(VMware)) {
-                case VMware:
                     templateName = VirtualNetworkApplianceManager.RouterTemplateVmware.valueIn(dest.getDataCenter().getId());
-                    break;
+                } else if (hType.equals(Hyperv)) {
-                case Hyperv:
                     templateName = VirtualNetworkApplianceManager.RouterTemplateHyperV.valueIn(dest.getDataCenter().getId());
-                    break;
+                } else if (hType.equals(LXC)) {
-                case LXC:
                     templateName = VirtualNetworkApplianceManager.RouterTemplateLxc.valueIn(dest.getDataCenter().getId());
-                    break;
-                default:
-                    break;
                 }
                 final VMTemplateVO template = _templateDao.findRoutingTemplate(hType, templateName);
 

plugins/network-elements/ovs/src/main/java/com/cloud/network/ovs/OvsTunnelManagerImpl.java

@@ -29,6 +29,7 @@ import javax.persistence.EntityExistsException;
 import org.apache.cloudstack.framework.config.dao.ConfigurationDao;
 import org.apache.cloudstack.framework.messagebus.MessageBus;
 import org.apache.cloudstack.framework.messagebus.MessageSubscriber;
+import org.apache.commons.lang3.StringUtils;
 import org.springframework.stereotype.Component;
 
 import com.cloud.agent.AgentManager;
@@ -240,23 +241,18 @@ public class OvsTunnelManagerImpl extends ManagerBase implements OvsTunnelManage
         HypervisorType hvType = host.getHypervisorType();
 
         String label = null;
-        switch (hvType) {
+        if (hvType.equals(HypervisorType.XenServer)) {
-        case XenServer:
             label = physNetTT.getXenNetworkLabel();
-            if ((label != null) && (!label.equals(""))) {
+            if (StringUtils.isNotBlank(label)) {
                 physNetLabel = label;
             }
-            break;
+        } else if (hvType.equals(HypervisorType.KVM)) {
-        case KVM:
             label = physNetTT.getKvmNetworkLabel();
-            if ((label != null) && (!label.equals(""))) {
+            if (StringUtils.isNotBlank(label)) {
                 physNetLabel = label;
             }
-            break;
+        } else {
-        default:
+            throw new CloudRuntimeException(String.format("Hypervisor %s unsupported by OVS Tunnel Manager", hvType));
-            throw new CloudRuntimeException("Hypervisor " +
-                    hvType.toString() +
-                    " unsupported by OVS Tunnel Manager");
         }
 
         // Try to fetch GRE endpoint IP address for cloud db

server/src/main/java/com/cloud/api/query/vo/DomainRouterJoinVO.java

@@ -20,6 +20,7 @@ import java.net.URI;
 import java.util.Date;
 
 import javax.persistence.Column;
+import javax.persistence.Convert;
 import javax.persistence.Entity;
 import javax.persistence.EnumType;
 import javax.persistence.Enumerated;
@@ -37,6 +38,7 @@ import com.cloud.user.Account;
 import com.cloud.utils.db.GenericDao;
 import com.cloud.vm.VirtualMachine;
 import com.cloud.vm.VirtualMachine.State;
+import org.apache.cloudstack.util.HypervisorTypeConverter;
 
 @Entity
 @Table(name = "domain_router_view")
@@ -138,7 +140,7 @@ public class DomainRouterJoinVO extends BaseViewVO implements ControlledViewEnti
     private ResourceState hostResourceState;
 
     @Column(name="hypervisor_type")
-    @Enumerated(value=EnumType.STRING)
+    @Convert(converter = HypervisorTypeConverter.class)
     private Hypervisor.HypervisorType hypervisorType;
 
     @Column(name = "template_id", updatable = true, nullable = true, length = 17)

server/src/main/java/com/cloud/api/query/vo/HostJoinVO.java

@@ -20,6 +20,7 @@ import java.util.Arrays;
 import java.util.Date;
 
 import javax.persistence.Column;
+import javax.persistence.Convert;
 import javax.persistence.Entity;
 import javax.persistence.EnumType;
 import javax.persistence.Enumerated;
@@ -38,6 +39,7 @@ import org.apache.cloudstack.api.Identity;
 import org.apache.cloudstack.api.InternalIdentity;
 import org.apache.cloudstack.ha.HAConfig;
 import org.apache.cloudstack.outofbandmanagement.OutOfBandManagement;
+import org.apache.cloudstack.util.HypervisorTypeConverter;
 import org.apache.commons.lang3.StringUtils;
 
 /**
@@ -76,7 +78,7 @@ public class HostJoinVO extends BaseViewVO implements InternalIdentity, Identity
     private String version;
 
     @Column(name = "hypervisor_type")
-    @Enumerated(value = EnumType.STRING)
+    @Convert(converter = HypervisorTypeConverter.class)
     private HypervisorType hypervisorType;
 
     @Column(name = "hypervisor_version")

server/src/main/java/com/cloud/api/query/vo/SnapshotJoinVO.java

@@ -20,6 +20,7 @@ package com.cloud.api.query.vo;
 import java.util.Date;
 
 import javax.persistence.Column;
+import javax.persistence.Convert;
 import javax.persistence.Entity;
 import javax.persistence.EnumType;
 import javax.persistence.Enumerated;
@@ -34,6 +35,7 @@ import com.cloud.storage.VMTemplateStorageResourceAssoc;
 import com.cloud.storage.Volume;
 import com.cloud.user.Account;
 import com.cloud.utils.db.GenericDao;
+import org.apache.cloudstack.util.HypervisorTypeConverter;
 
 @Entity
 @Table(name = "snapshot_view")
@@ -71,7 +73,7 @@ public class SnapshotJoinVO extends BaseViewWithTagInformationVO implements Cont
     private Snapshot.LocationType locationType;
 
     @Column(name = "hypervisor_type")
-    @Enumerated(value = EnumType.STRING)
+    @Convert(converter = HypervisorTypeConverter.class)
     Hypervisor.HypervisorType hypervisorType;
 
     @Column(name = "account_id")

server/src/main/java/com/cloud/api/query/vo/StoragePoolJoinVO.java

@@ -36,6 +36,7 @@ import com.cloud.storage.ScopeType;
 import com.cloud.storage.Storage.StoragePoolType;
 import com.cloud.storage.StoragePoolStatus;
 import com.cloud.utils.db.GenericDao;
+import org.apache.cloudstack.util.HypervisorTypeConverter;
 
 /**
  * Storage Pool DB view.
@@ -138,7 +139,7 @@ public class StoragePoolJoinVO extends BaseViewVO implements InternalIdentity, I
     private Long capacityIops;
 
     @Column(name = "hypervisor")
-    @Enumerated(value = EnumType.STRING)
+    @Convert(converter = HypervisorTypeConverter.class)
     private HypervisorType hypervisor;
 
     @Column(name = "storage_provider_name")

server/src/main/java/com/cloud/api/query/vo/TemplateJoinVO.java

@@ -19,6 +19,7 @@ package com.cloud.api.query.vo;
 import java.util.Date;
 
 import javax.persistence.Column;
+import javax.persistence.Convert;
 import javax.persistence.Entity;
 import javax.persistence.EnumType;
 import javax.persistence.Enumerated;
@@ -36,6 +37,7 @@ import com.cloud.storage.VMTemplateStorageResourceAssoc.Status;
 import com.cloud.template.VirtualMachineTemplate;
 import com.cloud.template.VirtualMachineTemplate.State;
 import com.cloud.utils.db.GenericDao;
+import org.apache.cloudstack.util.HypervisorTypeConverter;
 
 @Entity
 @Table(name = "template_view")
@@ -114,7 +116,7 @@ public class TemplateJoinVO extends BaseViewWithTagInformationVO implements Cont
     private boolean crossZones = false;
 
     @Column(name = "hypervisor_type")
-    @Enumerated(value = EnumType.STRING)
+    @Convert(converter = HypervisorTypeConverter.class)
     private HypervisorType hypervisorType;
 
     @Column(name = "extractable")

server/src/main/java/com/cloud/api/query/vo/UserVmJoinVO.java

@@ -43,6 +43,7 @@ import com.cloud.util.StoragePoolTypeConverter;
 import com.cloud.utils.db.GenericDao;
 import com.cloud.vm.VirtualMachine;
 import com.cloud.vm.VirtualMachine.State;
+import org.apache.cloudstack.util.HypervisorTypeConverter;
 
 @Entity
 @Table(name = "user_vm_view")
@@ -128,7 +129,7 @@ public class UserVmJoinVO extends BaseViewWithTagInformationVO implements Contro
     private String guestOsUuid;
 
     @Column(name = "hypervisor_type")
-    @Enumerated(value = EnumType.STRING)
+    @Convert(converter = HypervisorTypeConverter.class)
     private HypervisorType hypervisorType;
 
     @Column(name = "ha_enabled", updatable = true, nullable = true)

server/src/main/java/com/cloud/api/query/vo/VolumeJoinVO.java

@@ -19,6 +19,7 @@ package com.cloud.api.query.vo;
 import java.util.Date;
 
 import javax.persistence.Column;
+import javax.persistence.Convert;
 import javax.persistence.Entity;
 import javax.persistence.EnumType;
 import javax.persistence.Enumerated;
@@ -33,6 +34,7 @@ import com.cloud.storage.Volume;
 import com.cloud.user.Account;
 import com.cloud.utils.db.GenericDao;
 import com.cloud.vm.VirtualMachine;
+import org.apache.cloudstack.util.HypervisorTypeConverter;
 
 @Entity
 @Table(name = "volume_view")
@@ -179,7 +181,7 @@ public class VolumeJoinVO extends BaseViewWithTagInformationVO implements Contro
     private String errorString;
 
     @Column(name = "hypervisor_type")
-    @Enumerated(value = EnumType.STRING)
+    @Convert(converter = HypervisorTypeConverter.class)
     private HypervisorType hypervisorType;
 
     @Column(name = "disk_offering_id")

server/src/main/java/com/cloud/network/NetworkModelImpl.java

@@ -1300,22 +1300,16 @@ public class NetworkModelImpl extends ManagerBase implements NetworkModel, Confi
             PhysicalNetworkTrafficTypeVO mgmtTraffic = _pNTrafficTypeDao.findBy(mgmtPhyNetwork.getId(), TrafficType.Management);
             if (mgmtTraffic != null) {
                 String label = null;
-                switch (hypervisorType) {
+                if (hypervisorType.equals(HypervisorType.XenServer)) {
-                    case XenServer:
+                    label = mgmtTraffic.getXenNetworkLabel();
-                        label = mgmtTraffic.getXenNetworkLabel();
+                } else if (hypervisorType.equals(HypervisorType.KVM)) {
-                        break;
+                    label = mgmtTraffic.getKvmNetworkLabel();
-                    case KVM:
+                } else if (hypervisorType.equals(HypervisorType.VMware)) {
-                        label = mgmtTraffic.getKvmNetworkLabel();
+                    label = mgmtTraffic.getVmwareNetworkLabel();
-                        break;
+                } else if (hypervisorType.equals(HypervisorType.Hyperv)) {
-                    case VMware:
+                    label = mgmtTraffic.getHypervNetworkLabel();
-                        label = mgmtTraffic.getVmwareNetworkLabel();
+                } else if (hypervisorType.equals(HypervisorType.Ovm3)) {
-                        break;
+                    label = mgmtTraffic.getOvm3NetworkLabel();
-                    case Hyperv:
-                        label = mgmtTraffic.getHypervNetworkLabel();
-                        break;
-                    case Ovm3:
-                        label = mgmtTraffic.getOvm3NetworkLabel();
-                        break;
                 }
                 return label;
             }
@@ -1335,22 +1329,16 @@ public class NetworkModelImpl extends ManagerBase implements NetworkModel, Confi
             PhysicalNetworkTrafficTypeVO storageTraffic = _pNTrafficTypeDao.findBy(storagePhyNetwork.getId(), TrafficType.Storage);
             if (storageTraffic != null) {
                 String label = null;
-                switch (hypervisorType) {
+                if (hypervisorType.equals(HypervisorType.XenServer)) {
-                    case XenServer:
+                    label = storageTraffic.getXenNetworkLabel();
-                        label = storageTraffic.getXenNetworkLabel();
+                } else if (hypervisorType.equals(HypervisorType.KVM)) {
-                        break;
+                    label = storageTraffic.getKvmNetworkLabel();
-                    case KVM:
+                } else if (hypervisorType.equals(HypervisorType.VMware)) {
-                        label = storageTraffic.getKvmNetworkLabel();
+                    label = storageTraffic.getVmwareNetworkLabel();
-                        break;
+                } else if (hypervisorType.equals(HypervisorType.Hyperv)) {
-                    case VMware:
+                    label = storageTraffic.getHypervNetworkLabel();
-                        label = storageTraffic.getVmwareNetworkLabel();
+                } else if (hypervisorType.equals(HypervisorType.Ovm3)) {
-                        break;
+                    label = storageTraffic.getOvm3NetworkLabel();
-                    case Hyperv:
-                        label = storageTraffic.getHypervNetworkLabel();
-                        break;
-                    case Ovm3:
-                        label = storageTraffic.getOvm3NetworkLabel();
-                        break;
                 }
                 return label;
             }
@@ -1860,22 +1848,16 @@ public class NetworkModelImpl extends ManagerBase implements NetworkModel, Confi
             PhysicalNetworkTrafficTypeVO publicTraffic = _pNTrafficTypeDao.findBy(publicPhyNetwork.getId(), TrafficType.Public);
             if (publicTraffic != null) {
                 String label = null;
-                switch (hypervisorType) {
+                if (hypervisorType.equals(HypervisorType.XenServer)) {
-                    case XenServer:
+                    label = publicTraffic.getXenNetworkLabel();
-                        label = publicTraffic.getXenNetworkLabel();
+                } else if (hypervisorType.equals(HypervisorType.KVM)) {
-                        break;
+                    label = publicTraffic.getKvmNetworkLabel();
-                    case KVM:
+                } else if (hypervisorType.equals(HypervisorType.VMware)) {
-                        label = publicTraffic.getKvmNetworkLabel();
+                    label = publicTraffic.getVmwareNetworkLabel();
-                        break;
+                } else if (hypervisorType.equals(HypervisorType.Hyperv)) {
-                    case VMware:
+                    label = publicTraffic.getHypervNetworkLabel();
-                        label = publicTraffic.getVmwareNetworkLabel();
+                } else if (hypervisorType.equals(HypervisorType.Ovm3)) {
-                        break;
+                    label = publicTraffic.getOvm3NetworkLabel();
-                    case Hyperv:
-                        label = publicTraffic.getHypervNetworkLabel();
-                        break;
-                    case Ovm3:
-                        label = publicTraffic.getOvm3NetworkLabel();
-                        break;
                 }
                 return label;
             }
@@ -1895,22 +1877,16 @@ public class NetworkModelImpl extends ManagerBase implements NetworkModel, Confi
             PhysicalNetworkTrafficTypeVO guestTraffic = _pNTrafficTypeDao.findBy(guestPhyNetwork.getId(), TrafficType.Guest);
             if (guestTraffic != null) {
                 String label = null;
-                switch (hypervisorType) {
+                if (hypervisorType.equals(HypervisorType.XenServer)) {
-                    case XenServer:
+                    label = guestTraffic.getXenNetworkLabel();
-                        label = guestTraffic.getXenNetworkLabel();
+                } else if (hypervisorType.equals(HypervisorType.KVM)) {
-                        break;
+                    label = guestTraffic.getKvmNetworkLabel();
-                    case KVM:
+                } else if (hypervisorType.equals(HypervisorType.VMware)) {
-                        label = guestTraffic.getKvmNetworkLabel();
+                    label = guestTraffic.getVmwareNetworkLabel();
-                        break;
+                } else if (hypervisorType.equals(HypervisorType.Hyperv)) {
-                    case VMware:
+                    label = guestTraffic.getHypervNetworkLabel();
-                        label = guestTraffic.getVmwareNetworkLabel();
+                } else if (hypervisorType.equals(HypervisorType.Ovm3)) {
-                        break;
+                    label = guestTraffic.getOvm3NetworkLabel();
-                    case Hyperv:
-                        label = guestTraffic.getHypervNetworkLabel();
-                        break;
-                    case Ovm3:
-                        label = guestTraffic.getOvm3NetworkLabel();
-                        break;
                 }
                 return label;
             }

server/src/main/java/com/cloud/storage/StorageManagerImpl.java

@@ -3094,24 +3094,16 @@ public class StorageManagerImpl extends ManagerBase implements StorageManager, C
 
     private String getValidTemplateName(Long zoneId, HypervisorType hType) {
         String templateName = null;
-        switch (hType) {
+        if (hType.equals(HypervisorType.XenServer)) {
-            case XenServer:
+            templateName = VirtualNetworkApplianceManager.RouterTemplateXen.valueIn(zoneId);
-                templateName = VirtualNetworkApplianceManager.RouterTemplateXen.valueIn(zoneId);
+        } else if (hType.equals(HypervisorType.KVM)) {
-                break;
+            templateName = VirtualNetworkApplianceManager.RouterTemplateKvm.valueIn(zoneId);
-            case KVM:
+        } else if (hType.equals(HypervisorType.VMware)) {
-                templateName = VirtualNetworkApplianceManager.RouterTemplateKvm.valueIn(zoneId);
+            templateName = VirtualNetworkApplianceManager.RouterTemplateVmware.valueIn(zoneId);
-                break;
+        } else if (hType.equals(HypervisorType.Hyperv)) {
-            case VMware:
+            templateName = VirtualNetworkApplianceManager.RouterTemplateHyperV.valueIn(zoneId);
-                templateName = VirtualNetworkApplianceManager.RouterTemplateVmware.valueIn(zoneId);
+        } else if (hType.equals(HypervisorType.LXC)) {
-                break;
+            templateName = VirtualNetworkApplianceManager.RouterTemplateLxc.valueIn(zoneId);
-            case Hyperv:
-                templateName = VirtualNetworkApplianceManager.RouterTemplateHyperV.valueIn(zoneId);
-                break;
-            case LXC:
-                templateName = VirtualNetworkApplianceManager.RouterTemplateLxc.valueIn(zoneId);
-                break;
-            default:
-                break;
         }
         return templateName;
     }

server/src/main/java/com/cloud/template/TemplateAdapterBase.java

@@ -17,6 +17,7 @@
 package com.cloud.template;
 
 import java.util.ArrayList;
+import java.util.Arrays;
 import java.util.HashMap;
 import java.util.List;
 import java.util.Map;
@@ -81,6 +82,7 @@ import com.cloud.utils.component.AdapterBase;
 import com.cloud.utils.exception.CloudRuntimeException;
 import com.cloud.vm.UserVmVO;
 import com.cloud.vm.dao.UserVmDao;
+import org.apache.commons.lang3.StringUtils;
 
 public abstract class TemplateAdapterBase extends AdapterBase implements TemplateAdapter {
     protected @Inject
@@ -285,8 +287,10 @@ public abstract class TemplateAdapterBase extends AdapterBase implements Templat
 
         HypervisorType hypervisorType = HypervisorType.getType(cmd.getHypervisor());
         if(hypervisorType == HypervisorType.None) {
-            throw new InvalidParameterValueException("Hypervisor Type: " + cmd.getHypervisor() + " is invalid. Supported Hypervisor types are "
+            throw new InvalidParameterValueException(String.format(
-                    + EnumUtils.listValues(HypervisorType.values()).replace("None, ", ""));
+                    "Hypervisor Type: %s is invalid. Supported Hypervisor types are: %s",
+                    cmd.getHypervisor(),
+                    StringUtils.join(Arrays.stream(HypervisorType.values()).filter(h -> h != HypervisorType.None).map(HypervisorType::name).toArray(), ", ")));
         }
 
         Map details = cmd.getDetails();
@@ -327,8 +331,10 @@ public abstract class TemplateAdapterBase extends AdapterBase implements Templat
         }
 
         if(!params.isIso() && params.getHypervisorType() == HypervisorType.None) {
-            throw new InvalidParameterValueException("Hypervisor Type: " + params.getHypervisorType() + " is invalid. Supported Hypervisor types are "
+            throw new InvalidParameterValueException(String.format(
-                    + EnumUtils.listValues(HypervisorType.values()).replace("None, ", ""));
+                    "Hypervisor Type: %s is invalid. Supported Hypervisor types are: %s",
+                    params.getHypervisorType(),
+                    StringUtils.join(Arrays.stream(HypervisorType.values()).filter(h -> h != HypervisorType.None).map(HypervisorType::name).toArray(), ", ")));
         }
 
         return prepare(params.isIso(), params.getUserId(), params.getName(), params.getDisplayText(), params.getBits(),

server/src/main/java/com/cloud/vm/UserVmManagerImpl.java

@@ -6359,19 +6359,15 @@ public class UserVmManagerImpl extends ManagerBase implements UserVmManager, Vir
         String decodedUrl = decodeExtraConfig(extraConfig);
         HypervisorType hypervisorType = vm.getHypervisorType();
 
-        switch (hypervisorType) {
+        if (hypervisorType.equals(HypervisorType.XenServer)) {
-            case XenServer:
+            persistExtraConfigXenServer(decodedUrl, vm);
-                persistExtraConfigXenServer(decodedUrl, vm);
+        } else if (hypervisorType.equals(HypervisorType.KVM)) {
-                break;
+            persistExtraConfigKvm(decodedUrl, vm);
-            case KVM:
+        } else if (hypervisorType.equals(HypervisorType.VMware)) {
-                persistExtraConfigKvm(decodedUrl, vm);
+            persistExtraConfigVmware(decodedUrl, vm);
-                break;
+        } else {
-            case VMware:
+            String msg = String.format("This hypervisor %s is not supported for use with this feature", hypervisorType.toString());
-                persistExtraConfigVmware(decodedUrl, vm);
+            throw new CloudRuntimeException(msg);
-                break;
-            default:
-                String msg = String.format("This hypervisor %s is not supported for use with this feature", hypervisorType.toString());
-                throw new CloudRuntimeException(msg);
         }
     }