diff --git a/apps/artemis/src/main/java/org/onosproject/artemis/impl/moas/MoasClientController.java b/apps/artemis/src/main/java/org/onosproject/artemis/impl/moas/MoasClientController.java
index fccda3e..7c1e01f 100644
--- a/apps/artemis/src/main/java/org/onosproject/artemis/impl/moas/MoasClientController.java
+++ b/apps/artemis/src/main/java/org/onosproject/artemis/impl/moas/MoasClientController.java
@@ -82,18 +82,13 @@
      * Bootstrap netty socket.
      *
      * @return bootstrap
-     * @throws Exception exception
      */
-    private Bootstrap createBootstrap() throws Exception {
-        try {
-            workerGroup = new NioEventLoopGroup();
-            return new Bootstrap()
-                    .group(workerGroup)
-                    .channel(NioSocketChannel.class)
-                    .option(ChannelOption.SO_KEEPALIVE, true);
-        } catch (Exception e) {
-            throw new Exception(e);
-        }
+    private Bootstrap createBootstrap() {
+        workerGroup = new NioEventLoopGroup();
+        return new Bootstrap()
+                .group(workerGroup)
+                .channel(NioSocketChannel.class)
+                .option(ChannelOption.SO_KEEPALIVE, true);
     }
 
     /**
diff --git a/apps/artemis/src/main/java/org/onosproject/artemis/impl/moas/MoasServerController.java b/apps/artemis/src/main/java/org/onosproject/artemis/impl/moas/MoasServerController.java
index c27a134..33e30d0 100644
--- a/apps/artemis/src/main/java/org/onosproject/artemis/impl/moas/MoasServerController.java
+++ b/apps/artemis/src/main/java/org/onosproject/artemis/impl/moas/MoasServerController.java
@@ -77,22 +77,17 @@
      * Create netty server bootstrap.
      *
      * @return bootstrap
-     * @throws Exception exception
      */
-    private ServerBootstrap createServerBootStrap() throws Exception {
-        try {
-            bossGroup = new NioEventLoopGroup();
-            workerGroup = new NioEventLoopGroup();
+    private ServerBootstrap createServerBootStrap() {
+        bossGroup = new NioEventLoopGroup();
+        workerGroup = new NioEventLoopGroup();
 
-            return new ServerBootstrap()
-                    .group(bossGroup, workerGroup)
-                    .channel(NioServerSocketChannel.class)
-                    .option(ChannelOption.SO_REUSEADDR, true)
-                    .childOption(ChannelOption.SO_KEEPALIVE, true)
-                    .childOption(ChannelOption.TCP_NODELAY, true);
-        } catch (Exception e) {
-            throw new Exception(e);
-        }
+        return new ServerBootstrap()
+                .group(bossGroup, workerGroup)
+                .channel(NioServerSocketChannel.class)
+                .option(ChannelOption.SO_REUSEADDR, true)
+                .childOption(ChannelOption.SO_KEEPALIVE, true)
+                .childOption(ChannelOption.TCP_NODELAY, true);
     }
 
     /**
diff --git a/apps/cpman/app/src/main/java/org/onosproject/cpman/impl/ControlMessageMetricMapper.java b/apps/cpman/app/src/main/java/org/onosproject/cpman/impl/ControlMessageMetricMapper.java
index bd541b4..92126bf 100644
--- a/apps/cpman/app/src/main/java/org/onosproject/cpman/impl/ControlMessageMetricMapper.java
+++ b/apps/cpman/app/src/main/java/org/onosproject/cpman/impl/ControlMessageMetricMapper.java
@@ -58,7 +58,7 @@
      */
     private static <I, O> O lookup(BiMap<I, O> map, I input, Class<O> cls) {
         if (!map.containsKey(input)) {
-            throw new RuntimeException(
+            throw new IllegalArgumentException(
                     String.format("No mapping found for %s when converting to %s",
                             input, cls.getName()));
         }
diff --git a/apps/l3vpn/src/main/java/org/onosproject/l3vpn/netl3vpn/impl/NetL3VpnManager.java b/apps/l3vpn/src/main/java/org/onosproject/l3vpn/netl3vpn/impl/NetL3VpnManager.java
index 0cb86ab..45e9f9b 100644
--- a/apps/l3vpn/src/main/java/org/onosproject/l3vpn/netl3vpn/impl/NetL3VpnManager.java
+++ b/apps/l3vpn/src/main/java/org/onosproject/l3vpn/netl3vpn/impl/NetL3VpnManager.java
@@ -240,7 +240,7 @@
             value = l3VpnIdGen.getNewId();
         }
         if (value > ID_LIMIT) {
-            throw new RuntimeException(ID_LIMIT_EXCEEDED);
+            throw new IllegalStateException(ID_LIMIT_EXCEEDED);
         }
         return CONS_HUNDRED + String.valueOf(value);
     }
diff --git a/apps/netconf/client/src/main/java/org/onosproject/netconf/client/impl/NetconfActiveComponent.java b/apps/netconf/client/src/main/java/org/onosproject/netconf/client/impl/NetconfActiveComponent.java
index 2c35f26..92043d5 100644
--- a/apps/netconf/client/src/main/java/org/onosproject/netconf/client/impl/NetconfActiveComponent.java
+++ b/apps/netconf/client/src/main/java/org/onosproject/netconf/client/impl/NetconfActiveComponent.java
@@ -212,7 +212,7 @@
         if (node.type() == DataNode.Type.SINGLE_INSTANCE_LEAF_VALUE_NODE) {
             temp = ((LeafNode) node).asString().split("\\:");
             if (temp.length != 3) {
-                throw new RuntimeException(new NetconfException("Invalid device id form, cannot apply"));
+                throw new IllegalStateException(new NetconfException("Invalid device id form, cannot apply"));
             }
             ip = temp[1];
             port = temp[2];
@@ -220,12 +220,12 @@
             ListKey key = (ListKey) node.key();
             temp = key.keyLeafs().get(0).leafValAsString().split("\\:");
             if (temp.length != 3) {
-                throw new RuntimeException(new NetconfException("Invalid device id form, cannot apply"));
+                throw new IllegalStateException(new NetconfException("Invalid device id form, cannot apply"));
             }
             ip = temp[1];
             port = temp[2];
         } else {
-            throw new RuntimeException(new NetconfException("Invalid device id type, cannot apply"));
+            throw new IllegalStateException(new NetconfException("Invalid device id type, cannot apply"));
         }
         try {
             return DeviceId.deviceId(new URI("netconf", ip + ":" + port, (String) null));
@@ -246,7 +246,7 @@
                 this.controller.connectDevice(deviceId);
                 //}
             } catch (Exception ex) {
-                throw new RuntimeException(new NetconfException("Unable to connect to NETCONF device on " +
+                throw new IllegalStateException(new NetconfException("Unable to connect to NETCONF device on " +
                         deviceId, ex));
             }
         }
@@ -263,21 +263,21 @@
         String resId = ResourceIdParser.parseResId(path);
         String[] el = resId.split(ResourceIdParser.EL_CHK);
         if (el.length < 3) {
-            throw new RuntimeException(new NetconfException("Invalid resource id, cannot apply"));
+            throw new IllegalStateException(new NetconfException("Invalid resource id, cannot apply"));
         }
         if (!el[2].contains((ResourceIdParser.KEY_SEP))) {
-            throw new RuntimeException(new NetconfException("Invalid device id key, cannot apply"));
+            throw new IllegalStateException(new NetconfException("Invalid device id key, cannot apply"));
         }
         String[] keys = el[2].split(ResourceIdParser.KEY_CHK);
         if (keys.length < 2) {
-            throw new RuntimeException(new NetconfException("Invalid device id key, cannot apply"));
+            throw new IllegalStateException(new NetconfException("Invalid device id key, cannot apply"));
         }
         String[] parts = keys[1].split(ResourceIdParser.NM_CHK);
         if (parts.length < 3) {
-            throw new RuntimeException(new NetconfException("Invalid device id key, cannot apply"));
+            throw new IllegalStateException(new NetconfException("Invalid device id key, cannot apply"));
         }
         if (parts[2].split("\\:").length != 3) {
-            throw new RuntimeException(new NetconfException("Invalid device id form, cannot apply"));
+            throw new IllegalStateException(new NetconfException("Invalid device id form, cannot apply"));
         }
         return (new ResourceId.Builder()
                 .addBranchPointSchema(el[1].split(ResourceIdParser.NM_CHK)[0],
@@ -299,23 +299,23 @@
         String resId = ResourceIdParser.parseResId(path);
         String[] el = resId.split(ResourceIdParser.EL_CHK);
         if (el.length < 3) {
-            throw new RuntimeException(new NetconfException("Invalid resource id, cannot apply"));
+            throw new IllegalStateException(new NetconfException("Invalid resource id, cannot apply"));
         }
         if (!el[2].contains((ResourceIdParser.KEY_SEP))) {
-            throw new RuntimeException(new NetconfException("Invalid device id key, cannot apply"));
+            throw new IllegalStateException(new NetconfException("Invalid device id key, cannot apply"));
         }
         String[] keys = el[2].split(ResourceIdParser.KEY_CHK);
         if (keys.length < 2) {
-            throw new RuntimeException(new NetconfException("Invalid device id key, cannot apply"));
+            throw new IllegalStateException(new NetconfException("Invalid device id key, cannot apply"));
         }
         String[] parts = keys[1].split(ResourceIdParser.NM_CHK);
         if (parts.length < 3) {
-            throw new RuntimeException(new NetconfException("Invalid device id key, cannot apply"));
+            throw new IllegalStateException(new NetconfException("Invalid device id key, cannot apply"));
         }
         String[] temp = parts[2].split("\\:");
         String ip, port;
         if (temp.length != 3) {
-            throw new RuntimeException(new NetconfException("Invalid device id form, cannot apply"));
+            throw new IllegalStateException(new NetconfException("Invalid device id form, cannot apply"));
         }
         ip = temp[1];
         port = temp[2];
diff --git a/apps/p4-tutorial/pipeconf/src/main/java/org/onosproject/p4tutorial/pipeconf/PipeconfFactory.java b/apps/p4-tutorial/pipeconf/src/main/java/org/onosproject/p4tutorial/pipeconf/PipeconfFactory.java
index a1e65aa..5d37bd1 100644
--- a/apps/p4-tutorial/pipeconf/src/main/java/org/onosproject/p4tutorial/pipeconf/PipeconfFactory.java
+++ b/apps/p4-tutorial/pipeconf/src/main/java/org/onosproject/p4tutorial/pipeconf/PipeconfFactory.java
@@ -67,7 +67,7 @@
         try {
             pipelineModel = P4InfoParser.parse(P4INFO_URL);
         } catch (P4InfoParserException e) {
-            throw new RuntimeException(e);
+            throw new IllegalStateException(e);
         }
 
         return DefaultPiPipeconf.builder()
diff --git a/apps/rabbitmq/src/main/java/org/onosproject/rabbitmq/impl/MQServiceImpl.java b/apps/rabbitmq/src/main/java/org/onosproject/rabbitmq/impl/MQServiceImpl.java
index 11b46fb..2ecc5d2 100644
--- a/apps/rabbitmq/src/main/java/org/onosproject/rabbitmq/impl/MQServiceImpl.java
+++ b/apps/rabbitmq/src/main/java/org/onosproject/rabbitmq/impl/MQServiceImpl.java
@@ -91,7 +91,7 @@
                                             prop.getProperty(SENDER_QUEUE)),
                     msgOutQueue);
         } catch (Exception e) {
-            throw new RuntimeException(e);
+            throw new IllegalStateException(e);
         }
         manageSender.start();
     }
diff --git a/apps/routing/fpm/app/src/main/java/org/onosproject/routing/fpm/protocol/RouteAttributeDst.java b/apps/routing/fpm/app/src/main/java/org/onosproject/routing/fpm/protocol/RouteAttributeDst.java
index 1535100..2962c0b 100644
--- a/apps/routing/fpm/app/src/main/java/org/onosproject/routing/fpm/protocol/RouteAttributeDst.java
+++ b/apps/routing/fpm/app/src/main/java/org/onosproject/routing/fpm/protocol/RouteAttributeDst.java
@@ -102,7 +102,7 @@
                 RouteAttribute.ROUTE_ATTRIBUTE_HEADER_LENGTH) {
             cb.writeBytes(buffer, Ip4Address.BYTE_LENGTH);
         } else {
-            throw new RuntimeException("Dst address length incorrect!");
+            throw new IllegalArgumentException("Dst address length incorrect!");
         }
     }
 }
diff --git a/apps/routing/fpm/app/src/main/java/org/onosproject/routing/fpm/protocol/RouteAttributeGateway.java b/apps/routing/fpm/app/src/main/java/org/onosproject/routing/fpm/protocol/RouteAttributeGateway.java
index 886f52e..3b1f5cd 100644
--- a/apps/routing/fpm/app/src/main/java/org/onosproject/routing/fpm/protocol/RouteAttributeGateway.java
+++ b/apps/routing/fpm/app/src/main/java/org/onosproject/routing/fpm/protocol/RouteAttributeGateway.java
@@ -104,7 +104,7 @@
                 RouteAttribute.ROUTE_ATTRIBUTE_HEADER_LENGTH) {
             cb.writeBytes(buffer, Ip4Address.BYTE_LENGTH);
         } else {
-            throw new RuntimeException("Gateway address length incorrect!");
+            throw new IllegalArgumentException("Gateway address length incorrect!");
         }
     }
 }
diff --git a/apps/vtn/vtnweb/src/main/java/org/onosproject/vtnweb/resources/FloatingIpWebResource.java b/apps/vtn/vtnweb/src/main/java/org/onosproject/vtnweb/resources/FloatingIpWebResource.java
index e958765..c510647 100644
--- a/apps/vtn/vtnweb/src/main/java/org/onosproject/vtnweb/resources/FloatingIpWebResource.java
+++ b/apps/vtn/vtnweb/src/main/java/org/onosproject/vtnweb/resources/FloatingIpWebResource.java
@@ -193,10 +193,8 @@
      *
      * @param floatingIpNodes the floatingIp json node
      * @return floatingIps a collection of floatingIp
-     * @throws Exception when any argument is illegal
      */
-    public Collection<FloatingIp> changeJsonToSub(JsonNode floatingIpNodes)
-            throws Exception {
+    public Collection<FloatingIp> changeJsonToSub(JsonNode floatingIpNodes) {
         checkNotNull(floatingIpNodes, JSON_NOT_NULL);
         Map<FloatingIpId, FloatingIp> subMap = new HashMap<FloatingIpId, FloatingIp>();
         if (!floatingIpNodes.hasNonNull("id")) {
diff --git a/apps/vtn/vtnweb/src/main/java/org/onosproject/vtnweb/resources/RouterWebResource.java b/apps/vtn/vtnweb/src/main/java/org/onosproject/vtnweb/resources/RouterWebResource.java
index c09b5cd..0d32a8d 100644
--- a/apps/vtn/vtnweb/src/main/java/org/onosproject/vtnweb/resources/RouterWebResource.java
+++ b/apps/vtn/vtnweb/src/main/java/org/onosproject/vtnweb/resources/RouterWebResource.java
@@ -131,7 +131,7 @@
             }
             return Response.status(CREATED).entity(result.toString()).build();
 
-        } catch (Exception e) {
+        } catch (IllegalArgumentException | IOException e) {
             return Response.status(BAD_REQUEST).entity(e.getMessage()).build();
         }
     }
@@ -271,8 +271,7 @@
         }
     }
 
-    private Collection<Router> createOrUpdateByInputStream(JsonNode subnode)
-            throws Exception {
+    private Collection<Router> createOrUpdateByInputStream(JsonNode subnode) {
         checkNotNull(subnode, JSON_NOT_NULL);
         JsonNode routerNode = subnode.get("routers");
         if (routerNode == null) {
@@ -281,7 +280,7 @@
         log.debug("routerNode is {}", routerNode.toString());
 
         if (routerNode.isArray()) {
-            throw new Exception("only singleton requests allowed");
+            throw new IllegalArgumentException("only singleton requests allowed");
         } else {
             return changeJsonToSub(routerNode);
         }
@@ -292,10 +291,8 @@
      *
      * @param routerNode the router json node
      * @return routers a collection of router
-     * @throws Exception when any argument is illegal
      */
-    public Collection<Router> changeJsonToSub(JsonNode routerNode)
-            throws Exception {
+    public Collection<Router> changeJsonToSub(JsonNode routerNode) {
         checkNotNull(routerNode, JSON_NOT_NULL);
         Map<RouterId, Router> subMap = new HashMap<RouterId, Router>();
         if (!routerNode.hasNonNull("id")) {
@@ -361,11 +358,9 @@
      * @param subnode the router json node
      * @param routerId the router identify
      * @return routers a collection of router
-     * @throws Exception when any argument is illegal
      */
     public Collection<Router> changeUpdateJsonToSub(JsonNode subnode,
-                                                    String routerId)
-                                                            throws Exception {
+                                                    String routerId) {
         checkNotNull(subnode, JSON_NOT_NULL);
         checkNotNull(routerId, "routerId should not be null");
         Map<RouterId, Router> subMap = new HashMap<RouterId, Router>();
diff --git a/core/api/src/main/java/org/onosproject/net/pi/model/DefaultPiPipeconf.java b/core/api/src/main/java/org/onosproject/net/pi/model/DefaultPiPipeconf.java
index b6cea63..7d9dd28 100644
--- a/core/api/src/main/java/org/onosproject/net/pi/model/DefaultPiPipeconf.java
+++ b/core/api/src/main/java/org/onosproject/net/pi/model/DefaultPiPipeconf.java
@@ -80,7 +80,7 @@
             try {
                 return Optional.of(extensions.get(type).openStream());
             } catch (IOException e) {
-                throw new RuntimeException(e);
+                throw new IllegalStateException(e);
             }
         } else {
             return Optional.empty();
diff --git a/core/net/src/main/java/org/onosproject/net/pi/impl/AbstractCriterionTranslator.java b/core/net/src/main/java/org/onosproject/net/pi/impl/AbstractCriterionTranslator.java
index 4bbb123..36e9068 100644
--- a/core/net/src/main/java/org/onosproject/net/pi/impl/AbstractCriterionTranslator.java
+++ b/core/net/src/main/java/org/onosproject/net/pi/impl/AbstractCriterionTranslator.java
@@ -112,7 +112,7 @@
                 }
                 break;
             default:
-                throw new RuntimeException("Unrecognized init type " + initType.name());
+                throw new IllegalArgumentException("Unrecognized init type " + initType.name());
         }
         return value;
     }
@@ -129,7 +129,7 @@
                 mask = getMaskFromPrefixLength(prefixLength, value.size());
                 break;
             default:
-                throw new RuntimeException("Unrecognized init type " + initType.name());
+                throw new IllegalArgumentException("Unrecognized init type " + initType.name());
         }
 
         return Pair.of(value, mask);
@@ -150,7 +150,7 @@
             case LPM:
                 break;
             default:
-                throw new RuntimeException("Unrecognized init type " + initType.name());
+                throw new IllegalArgumentException("Unrecognized init type " + initType.name());
         }
 
         return Pair.of(value, prefixLength);
diff --git a/core/net/src/main/java/org/onosproject/net/pi/impl/PiFlowRuleTranslatorImpl.java b/core/net/src/main/java/org/onosproject/net/pi/impl/PiFlowRuleTranslatorImpl.java
index 430e5e1..3230f41 100644
--- a/core/net/src/main/java/org/onosproject/net/pi/impl/PiFlowRuleTranslatorImpl.java
+++ b/core/net/src/main/java/org/onosproject/net/pi/impl/PiFlowRuleTranslatorImpl.java
@@ -428,7 +428,7 @@
                     return fieldMatch;
                 default:
                     // Should never be here.
-                    throw new RuntimeException(
+                    throw new IllegalArgumentException(
                             "Unrecognized match type " + fieldModel.matchType().name());
             }
         } catch (ByteSequenceTrimException e) {
diff --git a/core/net/src/main/java/org/onosproject/net/pi/impl/PiUtils.java b/core/net/src/main/java/org/onosproject/net/pi/impl/PiUtils.java
index 78bca5f..6f8d33a 100644
--- a/core/net/src/main/java/org/onosproject/net/pi/impl/PiUtils.java
+++ b/core/net/src/main/java/org/onosproject/net/pi/impl/PiUtils.java
@@ -54,7 +54,8 @@
                         .orElse(null)
                         .newInstance();
             } catch (InstantiationException | IllegalAccessException e) {
-                throw new RuntimeException(format("Unable to instantiate interpreter of pipeconf %s", pipeconf.id()));
+                throw new IllegalArgumentException(format("Unable to instantiate interpreter of pipeconf %s",
+                                                          pipeconf.id()));
             }
         }
     }
diff --git a/core/store/dist/src/main/java/org/onosproject/store/cluster/messaging/impl/NettyMessagingManager.java b/core/store/dist/src/main/java/org/onosproject/store/cluster/messaging/impl/NettyMessagingManager.java
index a5c5f3b..d7e478b 100644
--- a/core/store/dist/src/main/java/org/onosproject/store/cluster/messaging/impl/NettyMessagingManager.java
+++ b/core/store/dist/src/main/java/org/onosproject/store/cluster/messaging/impl/NettyMessagingManager.java
@@ -158,7 +158,7 @@
     protected ClusterMetadataService clusterMetadataService;
 
     @Activate
-    public void activate() throws Exception {
+    public void activate() throws InterruptedException {
         ControllerNode localNode = clusterMetadataService.getLocalNode();
         getTlsParameters();
 
@@ -179,7 +179,7 @@
     }
 
     @Deactivate
-    public void deactivate() throws Exception {
+    public void deactivate() {
         if (started.get()) {
             serverGroup.shutdownGracefully();
             clientGroup.shutdownGracefully();
diff --git a/drivers/cisco/netconf/src/main/java/org/onosproject/drivers/cisco/CiscoIosDeviceDescription.java b/drivers/cisco/netconf/src/main/java/org/onosproject/drivers/cisco/CiscoIosDeviceDescription.java
index 8839c59..d52c470 100644
--- a/drivers/cisco/netconf/src/main/java/org/onosproject/drivers/cisco/CiscoIosDeviceDescription.java
+++ b/drivers/cisco/netconf/src/main/java/org/onosproject/drivers/cisco/CiscoIosDeviceDescription.java
@@ -49,7 +49,7 @@
         try {
             version = session.get(showVersionRequestBuilder());
         } catch (NetconfException e) {
-            throw new RuntimeException(new NetconfException("Failed to retrieve version info.", e));
+            throw new IllegalStateException(new NetconfException("Failed to retrieve version info.", e));
         }
 
         String[] details = TextBlockParserCisco.parseCiscoIosDeviceDetails(version);
diff --git a/drivers/juniper/src/main/java/org/onosproject/drivers/juniper/FlowRuleJuniperImpl.java b/drivers/juniper/src/main/java/org/onosproject/drivers/juniper/FlowRuleJuniperImpl.java
index d4c09dc..cb07843 100644
--- a/drivers/juniper/src/main/java/org/onosproject/drivers/juniper/FlowRuleJuniperImpl.java
+++ b/drivers/juniper/src/main/java/org/onosproject/drivers/juniper/FlowRuleJuniperImpl.java
@@ -100,7 +100,7 @@
         try {
             reply = session.get(routingTableBuilder());
         } catch (NetconfException e) {
-            throw new RuntimeException(new NetconfException("Failed to retrieve configuration.",
+            throw new IllegalStateException(new NetconfException("Failed to retrieve configuration.",
                     e));
         }
         Collection<StaticRoute> devicesStaticRoutes =
@@ -241,7 +241,7 @@
                 }
             }
         } catch (NetconfException e) {
-            throw new RuntimeException(new NetconfException("Failed to retrieve configuration.",
+            throw new IllegalStateException(new NetconfException("Failed to retrieve configuration.",
                     e));
         }
         return false;
@@ -335,7 +335,7 @@
         try {
             replay = session.get(commitBuilder());
         } catch (NetconfException e) {
-            throw new RuntimeException(new NetconfException("Failed to retrieve configuration.",
+            throw new IllegalStateException(new NetconfException("Failed to retrieve configuration.",
                     e));
         }
 
@@ -355,7 +355,7 @@
         try {
             replay = session.get(rollbackBuilder(0));
         } catch (NetconfException e) {
-            throw new RuntimeException(new NetconfException("Failed to retrieve configuration.",
+            throw new IllegalStateException(new NetconfException("Failed to retrieve configuration.",
                     e));
         }
 
diff --git a/drivers/oplink/src/main/java/org/onosproject/drivers/oplink/OplinkNetconfUtility.java b/drivers/oplink/src/main/java/org/onosproject/drivers/oplink/OplinkNetconfUtility.java
index 966821e..4662219 100644
--- a/drivers/oplink/src/main/java/org/onosproject/drivers/oplink/OplinkNetconfUtility.java
+++ b/drivers/oplink/src/main/java/org/onosproject/drivers/oplink/OplinkNetconfUtility.java
@@ -69,7 +69,7 @@
         try {
             reply = session.get(filter, null);
         } catch (NetconfException e) {
-            throw new RuntimeException(new NetconfException("Failed to retrieve configuration.", e));
+            throw new IllegalStateException(new NetconfException("Failed to retrieve configuration.", e));
         }
         return reply;
     }
@@ -88,7 +88,7 @@
         try {
             reply = session.getConfig(DatastoreId.RUNNING, filter);
         } catch (NetconfException e) {
-            throw new RuntimeException(new NetconfException("Failed to retrieve configuration.", e));
+            throw new IllegalStateException(new NetconfException("Failed to retrieve configuration.", e));
         }
         return reply;
     }
@@ -108,7 +108,7 @@
         try {
             reply = session.editConfig(DatastoreId.RUNNING, mode, cfg);
         } catch (NetconfException e) {
-            throw new RuntimeException(new NetconfException("Failed to edit configuration.", e));
+            throw new IllegalStateException(new NetconfException("Failed to edit configuration.", e));
         }
         return reply;
     }
diff --git a/drivers/polatis/netconf/src/main/java/org/onosproject/drivers/polatis/netconf/PolatisNetconfUtility.java b/drivers/polatis/netconf/src/main/java/org/onosproject/drivers/polatis/netconf/PolatisNetconfUtility.java
index 6b8080b..1cb8031 100644
--- a/drivers/polatis/netconf/src/main/java/org/onosproject/drivers/polatis/netconf/PolatisNetconfUtility.java
+++ b/drivers/polatis/netconf/src/main/java/org/onosproject/drivers/polatis/netconf/PolatisNetconfUtility.java
@@ -82,7 +82,7 @@
         try {
             reply = session.get(filter, null);
         } catch (NetconfException e) {
-            throw new RuntimeException(new NetconfException("Failed to retrieve configuration.", e));
+            throw new IllegalStateException(new NetconfException("Failed to retrieve configuration.", e));
         }
         return reply;
     }
@@ -100,7 +100,7 @@
         try {
             reply = session.getConfig(DatastoreId.RUNNING, filter);
         } catch (NetconfException e) {
-            throw new RuntimeException(new NetconfException("Failed to retrieve configuration.", e));
+            throw new IllegalStateException(new NetconfException("Failed to retrieve configuration.", e));
         }
         return reply;
     }
@@ -119,7 +119,7 @@
         try {
             reply = session.editConfig(DatastoreId.RUNNING, mode, cfg);
         } catch (NetconfException e) {
-            throw new RuntimeException(new NetconfException("Failed to edit configuration.", e));
+            throw new IllegalStateException(new NetconfException("Failed to edit configuration.", e));
         }
         return reply;
     }
@@ -223,7 +223,7 @@
         NetconfController controller = checkNotNull(handler.get(NetconfController.class));
         NetconfSession session = controller.getNetconfDevice(handler.data().deviceId()).getSession();
         if (session == null) {
-            throw new RuntimeException(new NetconfException("Failed to retrieve the netconf device."));
+            throw new IllegalStateException(new NetconfException("Failed to retrieve the netconf device."));
         }
         return session;
     }
diff --git a/pipelines/basic/src/main/java/org/onosproject/pipelines/basic/PipeconfLoader.java b/pipelines/basic/src/main/java/org/onosproject/pipelines/basic/PipeconfLoader.java
index 1a5d4d2..8b5bf60 100644
--- a/pipelines/basic/src/main/java/org/onosproject/pipelines/basic/PipeconfLoader.java
+++ b/pipelines/basic/src/main/java/org/onosproject/pipelines/basic/PipeconfLoader.java
@@ -112,7 +112,7 @@
         try {
             return P4InfoParser.parse(p4InfoUrl);
         } catch (P4InfoParserException e) {
-            throw new RuntimeException(e);
+            throw new IllegalStateException(e);
         }
     }
 }
diff --git a/protocols/bgp/ctl/src/main/java/org/onosproject/bgp/controller/impl/Controller.java b/protocols/bgp/ctl/src/main/java/org/onosproject/bgp/controller/impl/Controller.java
index e9a1f64..acd1c7b 100644
--- a/protocols/bgp/ctl/src/main/java/org/onosproject/bgp/controller/impl/Controller.java
+++ b/protocols/bgp/ctl/src/main/java/org/onosproject/bgp/controller/impl/Controller.java
@@ -129,7 +129,7 @@
             cg.add(serverChannel);
             log.info("Listening for Peer connection on {}", sa);
         } catch (Exception e) {
-            throw new RuntimeException(e);
+            throw new IllegalStateException(e);
         }
     }
 
diff --git a/protocols/isis/ctl/src/main/java/org/onosproject/isis/controller/impl/Controller.java b/protocols/isis/ctl/src/main/java/org/onosproject/isis/controller/impl/Controller.java
index 6deadfd..e8dc9f0 100644
--- a/protocols/isis/ctl/src/main/java/org/onosproject/isis/controller/impl/Controller.java
+++ b/protocols/isis/ctl/src/main/java/org/onosproject/isis/controller/impl/Controller.java
@@ -206,7 +206,7 @@
      * @param json posted json
      * @return list of processes configured
      */
-    private List<IsisProcess> getConfig(JsonNode json) throws Exception {
+    private List<IsisProcess> getConfig(JsonNode json) {
         List<IsisProcess> isisProcessesList = new ArrayList<>();
         JsonNode jsonNodes = json;
         if (jsonNodes == null) {
diff --git a/protocols/isis/ctl/src/main/java/org/onosproject/isis/controller/impl/lsdb/IsisLspQueueConsumer.java b/protocols/isis/ctl/src/main/java/org/onosproject/isis/controller/impl/lsdb/IsisLspQueueConsumer.java
index a43f424..ddee647 100644
--- a/protocols/isis/ctl/src/main/java/org/onosproject/isis/controller/impl/lsdb/IsisLspQueueConsumer.java
+++ b/protocols/isis/ctl/src/main/java/org/onosproject/isis/controller/impl/lsdb/IsisLspQueueConsumer.java
@@ -82,7 +82,7 @@
      *
      * @param wrapper LSP wrapper instance
      */
-    private void processRefreshLsp(LspWrapper wrapper) throws Exception {
+    private void processRefreshLsp(LspWrapper wrapper) {
         if (wrapper.isSelfOriginated()) { //self originated
             DefaultIsisInterface isisInterface = (DefaultIsisInterface) wrapper.isisInterface();
             Channel channel = isisInterface.channel();
diff --git a/protocols/isis/isisio/src/main/java/org/onosproject/isis/io/isispacket/IsisMessageReader.java b/protocols/isis/isisio/src/main/java/org/onosproject/isis/io/isispacket/IsisMessageReader.java
index c1d5f81..09cac03 100644
--- a/protocols/isis/isisio/src/main/java/org/onosproject/isis/io/isispacket/IsisMessageReader.java
+++ b/protocols/isis/isisio/src/main/java/org/onosproject/isis/io/isispacket/IsisMessageReader.java
@@ -105,7 +105,7 @@
      * @return ISIS header
      * @throws Exception
      */
-    private IsisHeader getIsisHeader(ChannelBuffer channelBuffer) throws Exception {
+    private IsisHeader getIsisHeader(ChannelBuffer channelBuffer) {
 
         IsisHeader isisHeader = new IsisHeader();
         isisHeader.setIrpDiscriminator(channelBuffer.readByte());
diff --git a/protocols/lisp/ctl/src/main/java/org/onosproject/lisp/ctl/impl/LispControllerBootstrap.java b/protocols/lisp/ctl/src/main/java/org/onosproject/lisp/ctl/impl/LispControllerBootstrap.java
index 9b05097..8e6bcf9 100644
--- a/protocols/lisp/ctl/src/main/java/org/onosproject/lisp/ctl/impl/LispControllerBootstrap.java
+++ b/protocols/lisp/ctl/src/main/java/org/onosproject/lisp/ctl/impl/LispControllerBootstrap.java
@@ -70,8 +70,8 @@
                 f.sync();
             }
 
-        } catch (Exception e) {
-            throw new RuntimeException(e);
+        } catch (InterruptedException e) {
+            Thread.currentThread().interrupt();
         }
     }
 
diff --git a/protocols/lisp/msg/src/main/java/org/onosproject/lisp/msg/authentication/LispMacAuthentication.java b/protocols/lisp/msg/src/main/java/org/onosproject/lisp/msg/authentication/LispMacAuthentication.java
index a6af0b6..20a2f2a 100644
--- a/protocols/lisp/msg/src/main/java/org/onosproject/lisp/msg/authentication/LispMacAuthentication.java
+++ b/protocols/lisp/msg/src/main/java/org/onosproject/lisp/msg/authentication/LispMacAuthentication.java
@@ -75,10 +75,10 @@
             return mac.doFinal(data);
         } catch (NoSuchAlgorithmException e) {
             log.warn(NOT_SUPPORT_ALGORITHM_MSG, algorithm, e.getMessage());
-            throw new RuntimeException(e);
+            throw new IllegalStateException(e);
         } catch (InvalidKeyException e) {
             log.warn(INVALID_KEY_MSG, key, e.getMessage());
-            throw new RuntimeException(e);
+            throw new IllegalArgumentException(e);
         }
     }
 }
diff --git a/protocols/netconf/ctl/src/main/java/org/onosproject/netconf/ctl/impl/NetconfStreamThread.java b/protocols/netconf/ctl/src/main/java/org/onosproject/netconf/ctl/impl/NetconfStreamThread.java
index a11af4e..e80e214 100644
--- a/protocols/netconf/ctl/src/main/java/org/onosproject/netconf/ctl/impl/NetconfStreamThread.java
+++ b/protocols/netconf/ctl/src/main/java/org/onosproject/netconf/ctl/impl/NetconfStreamThread.java
@@ -293,7 +293,7 @@
             }
         } catch (IOException e) {
             log.warn("Error in reading from the session for device {} ", netconfDeviceInfo, e);
-            throw new RuntimeException(new NetconfException("Error in reading from the session for device {}" +
+            throw new IllegalStateException(new NetconfException("Error in reading from the session for device {}" +
                     netconfDeviceInfo, e));
             //TODO should we send a socket closed message to listeners ?
         }
diff --git a/protocols/openflow/ctl/src/main/java/org/onosproject/openflow/controller/impl/Controller.java b/protocols/openflow/ctl/src/main/java/org/onosproject/openflow/controller/impl/Controller.java
index 99f47f8..578dae0 100644
--- a/protocols/openflow/ctl/src/main/java/org/onosproject/openflow/controller/impl/Controller.java
+++ b/protocols/openflow/ctl/src/main/java/org/onosproject/openflow/controller/impl/Controller.java
@@ -18,7 +18,6 @@
 
 import com.google.common.base.Strings;
 import com.google.common.collect.ImmutableList;
-
 import io.netty.bootstrap.ServerBootstrap;
 import io.netty.channel.ChannelOption;
 import io.netty.channel.EventLoopGroup;
@@ -29,7 +28,6 @@
 import io.netty.channel.nio.NioEventLoopGroup;
 import io.netty.channel.socket.nio.NioServerSocketChannel;
 import io.netty.util.concurrent.GlobalEventExecutor;
-
 import org.onlab.util.ItemNotFoundException;
 import org.onosproject.net.DeviceId;
 import org.onosproject.net.driver.DefaultDriverData;
@@ -50,9 +48,15 @@
 import javax.net.ssl.SSLContext;
 import javax.net.ssl.TrustManagerFactory;
 import java.io.FileInputStream;
+import java.io.IOException;
 import java.lang.management.ManagementFactory;
 import java.lang.management.RuntimeMXBean;
+import java.security.KeyManagementException;
 import java.security.KeyStore;
+import java.security.KeyStoreException;
+import java.security.NoSuchAlgorithmException;
+import java.security.UnrecoverableKeyException;
+import java.security.cert.CertificateException;
 import java.util.Dictionary;
 import java.util.HashMap;
 import java.util.List;
@@ -147,7 +151,6 @@
      */
     public void run() {
 
-        try {
             final ServerBootstrap bootstrap = createServerBootStrap();
             bootstrap.option(ChannelOption.SO_REUSEADDR, true);
             bootstrap.childOption(ChannelOption.SO_KEEPALIVE, true);
@@ -164,10 +167,6 @@
                 log.info("Listening for switch connections on {}", port);
             });
 
-        } catch (Exception e) {
-            throw new RuntimeException(e);
-        }
-
     }
 
     private ServerBootstrap createServerBootStrap() {
@@ -236,13 +235,9 @@
 
         cg = new DefaultChannelGroup(GlobalEventExecutor.INSTANCE);
 
-        try {
-            getTlsParameters();
-            if (enableOfTls) {
-                initSsl();
-            }
-        } catch (Exception ex) {
-            log.error("SSL init failed: {}", ex.getMessage());
+        getTlsParameters();
+        if (enableOfTls) {
+            initSsl();
         }
     }
 
@@ -274,19 +269,24 @@
         }
     }
 
-    private void initSsl() throws Exception {
-        TrustManagerFactory tmFactory = TrustManagerFactory.getInstance(TrustManagerFactory.getDefaultAlgorithm());
-        KeyStore ts = KeyStore.getInstance("JKS");
-        ts.load(new FileInputStream(tsLocation), tsPwd);
-        tmFactory.init(ts);
+    private void initSsl() {
+        try {
+            TrustManagerFactory tmFactory = TrustManagerFactory.getInstance(TrustManagerFactory.getDefaultAlgorithm());
+            KeyStore ts = KeyStore.getInstance("JKS");
+            ts.load(new FileInputStream(tsLocation), tsPwd);
+            tmFactory.init(ts);
 
-        KeyManagerFactory kmf = KeyManagerFactory.getInstance(KeyManagerFactory.getDefaultAlgorithm());
-        KeyStore ks = KeyStore.getInstance("JKS");
-        ks.load(new FileInputStream(ksLocation), ksPwd);
-        kmf.init(ks, ksPwd);
+            KeyManagerFactory kmf = KeyManagerFactory.getInstance(KeyManagerFactory.getDefaultAlgorithm());
+            KeyStore ks = KeyStore.getInstance("JKS");
+            ks.load(new FileInputStream(ksLocation), ksPwd);
+            kmf.init(ks, ksPwd);
 
-        sslContext = SSLContext.getInstance("TLS");
-        sslContext.init(kmf.getKeyManagers(), tmFactory.getTrustManagers(), null);
+            sslContext = SSLContext.getInstance("TLS");
+            sslContext.init(kmf.getKeyManagers(), tmFactory.getTrustManagers(), null);
+        } catch (NoSuchAlgorithmException | KeyStoreException | CertificateException |
+                IOException | KeyManagementException | UnrecoverableKeyException ex) {
+            log.error("SSL init failed: {}", ex.getMessage());
+        }
     }
 
     // **************
diff --git a/protocols/openflow/ctl/src/main/java/org/onosproject/openflow/controller/impl/OFChannelHandler.java b/protocols/openflow/ctl/src/main/java/org/onosproject/openflow/controller/impl/OFChannelHandler.java
index 414bd89..a9455b6 100644
--- a/protocols/openflow/ctl/src/main/java/org/onosproject/openflow/controller/impl/OFChannelHandler.java
+++ b/protocols/openflow/ctl/src/main/java/org/onosproject/openflow/controller/impl/OFChannelHandler.java
@@ -1357,9 +1357,9 @@
         return getSwitchInfoString();
     }
 
-    protected void channelIdle(ChannelHandlerContext ctx,
+    private void channelIdle(ChannelHandlerContext ctx,
                                IdleStateEvent e)
-            throws Exception {
+            throws IOException {
         OFMessage m = factory.buildEchoRequest().build();
         log.debug("Sending Echo Request on idle channel: {}",
                   ctx.channel());
diff --git a/protocols/openflow/ctl/src/main/java/org/onosproject/openflow/controller/impl/OFMessageEncoder.java b/protocols/openflow/ctl/src/main/java/org/onosproject/openflow/controller/impl/OFMessageEncoder.java
index 4c875ac..c541a9b 100644
--- a/protocols/openflow/ctl/src/main/java/org/onosproject/openflow/controller/impl/OFMessageEncoder.java
+++ b/protocols/openflow/ctl/src/main/java/org/onosproject/openflow/controller/impl/OFMessageEncoder.java
@@ -56,7 +56,7 @@
     @Override
     public void write(ChannelHandlerContext ctx,
                       Object msg,
-                      ChannelPromise promise) throws Exception {
+                      ChannelPromise promise) {
 
         ByteBuf buf = null;
         try {
diff --git a/protocols/ospf/api/src/main/java/org/onosproject/ospf/controller/OspfArea.java b/protocols/ospf/api/src/main/java/org/onosproject/ospf/controller/OspfArea.java
index f4e8255..a66160d 100644
--- a/protocols/ospf/api/src/main/java/org/onosproject/ospf/controller/OspfArea.java
+++ b/protocols/ospf/api/src/main/java/org/onosproject/ospf/controller/OspfArea.java
@@ -16,7 +16,6 @@
 package org.onosproject.ospf.controller;
 
 import org.onlab.packet.Ip4Address;
-import org.onosproject.ospf.exceptions.OspfParseException;
 
 import java.util.List;
 
@@ -200,9 +199,8 @@
      *
      * @param ospfLsa       LSA instance
      * @param ospfInterface interface instance
-     * @throws OspfParseException might throws exception
      */
-    void addLsa(OspfLsa ospfLsa, OspfInterface ospfInterface) throws OspfParseException;
+    void addLsa(OspfLsa ospfLsa, OspfInterface ospfInterface);
 
     /**
      * Sets router sequence number for router LSA.
diff --git a/protocols/pcep/server/ctl/src/main/java/org/onosproject/pcep/server/impl/Controller.java b/protocols/pcep/server/ctl/src/main/java/org/onosproject/pcep/server/impl/Controller.java
index c85e22a..f7f596c 100644
--- a/protocols/pcep/server/ctl/src/main/java/org/onosproject/pcep/server/impl/Controller.java
+++ b/protocols/pcep/server/ctl/src/main/java/org/onosproject/pcep/server/impl/Controller.java
@@ -205,7 +205,7 @@
             cg.add(bootstrap.bind(sa));
             log.debug("Listening for PCC connection on {}", sa);
         } catch (Exception e) {
-            throw new RuntimeException(e);
+            throw new IllegalStateException(e);
         }
     }
 
diff --git a/providers/netconf/device/src/main/java/org/onosproject/provider/netconf/device/impl/NetconfDeviceProvider.java b/providers/netconf/device/src/main/java/org/onosproject/provider/netconf/device/impl/NetconfDeviceProvider.java
index c35682c..99c8ebd 100644
--- a/providers/netconf/device/src/main/java/org/onosproject/provider/netconf/device/impl/NetconfDeviceProvider.java
+++ b/providers/netconf/device/src/main/java/org/onosproject/provider/netconf/device/impl/NetconfDeviceProvider.java
@@ -582,7 +582,7 @@
                 providerService.deviceDisconnected(deviceId);
             }
             deviceKeyAdminService.removeKey(DeviceKeyId.deviceKeyId(deviceId.toString()));
-            throw new RuntimeException(new NetconfException(
+            throw new IllegalStateException(new NetconfException(
                     "Can't connect to NETCONF device " + deviceId, e));
 
         }
diff --git a/providers/openflow/device/src/main/java/org/onosproject/provider/of/device/impl/OpenFlowDeviceProvider.java b/providers/openflow/device/src/main/java/org/onosproject/provider/of/device/impl/OpenFlowDeviceProvider.java
index b489c52..66ded21 100644
--- a/providers/openflow/device/src/main/java/org/onosproject/provider/of/device/impl/OpenFlowDeviceProvider.java
+++ b/providers/openflow/device/src/main/java/org/onosproject/provider/of/device/impl/OpenFlowDeviceProvider.java
@@ -1004,7 +1004,7 @@
                     sigType = CltSignalType.CLT_100GBE;
                     break;
                 default:
-                    throw new RuntimeException("Un recognize OduClt speed: " + portSpeedInMbps.toString());
+                    throw new IllegalArgumentException("Un recognize OduClt speed: " + portSpeedInMbps.toString());
             }
 
             SparseAnnotations annotations = buildOduCltAnnotation(port);
diff --git a/providers/openflow/device/src/main/java/org/onosproject/provider/of/device/impl/OpenFlowDeviceValueMapper.java b/providers/openflow/device/src/main/java/org/onosproject/provider/of/device/impl/OpenFlowDeviceValueMapper.java
index 28ebb3c..789e7e5 100644
--- a/providers/openflow/device/src/main/java/org/onosproject/provider/of/device/impl/OpenFlowDeviceValueMapper.java
+++ b/providers/openflow/device/src/main/java/org/onosproject/provider/of/device/impl/OpenFlowDeviceValueMapper.java
@@ -51,7 +51,7 @@
      */
     private static <I, O> O lookup(BiMap<I, O> map, I input, Class<O> cls) {
         if (!map.containsKey(input)) {
-            throw new RuntimeException(
+            throw new IllegalArgumentException(
                     String.format("No mapping found for %s when converting to %s", input, cls.getName()));
         }
 
diff --git a/providers/openflow/message/src/main/java/org/onosproject/provider/of/message/impl/OpenFlowControlMessageMapper.java b/providers/openflow/message/src/main/java/org/onosproject/provider/of/message/impl/OpenFlowControlMessageMapper.java
index 582484d..5b73e0f 100644
--- a/providers/openflow/message/src/main/java/org/onosproject/provider/of/message/impl/OpenFlowControlMessageMapper.java
+++ b/providers/openflow/message/src/main/java/org/onosproject/provider/of/message/impl/OpenFlowControlMessageMapper.java
@@ -59,7 +59,7 @@
      */
     private static <I, O> O lookup(BiMap<I, O> map, I input, Class<O> cls) {
         if (!map.containsKey(input)) {
-            throw new RuntimeException(
+            throw new IllegalArgumentException(
                     String.format("No mapping found for %s when converting to %s",
                             input, cls.getName()));
         }
diff --git a/utils/misc/src/main/java/org/onlab/packet/dhcp/Dhcp6ClientIdOption.java b/utils/misc/src/main/java/org/onlab/packet/dhcp/Dhcp6ClientIdOption.java
index 5623e71..f4f3fc8 100644
--- a/utils/misc/src/main/java/org/onlab/packet/dhcp/Dhcp6ClientIdOption.java
+++ b/utils/misc/src/main/java/org/onlab/packet/dhcp/Dhcp6ClientIdOption.java
@@ -49,7 +49,7 @@
             Dhcp6Duid duid = Dhcp6Duid.deserializer().deserialize(data, 0, data.length);
             this.setDuid(duid);
         } catch (DeserializationException e) {
-            throw new RuntimeException("Invalid DUID");
+            throw new IllegalArgumentException("Invalid DUID");
         }
 
     }
diff --git a/utils/misc/src/main/java/org/onlab/packet/dhcp/Dhcp6Duid.java b/utils/misc/src/main/java/org/onlab/packet/dhcp/Dhcp6Duid.java
index c8ca3bd..80675e2 100644
--- a/utils/misc/src/main/java/org/onlab/packet/dhcp/Dhcp6Duid.java
+++ b/utils/misc/src/main/java/org/onlab/packet/dhcp/Dhcp6Duid.java
@@ -51,7 +51,7 @@
                 case 3:
                     return DUID_LL;
                 default:
-                    throw new RuntimeException("Unknown type: " + type);
+                    throw new IllegalArgumentException("Unknown type: " + type);
             }
         }
     }
@@ -139,7 +139,7 @@
                 byteBuffer.put(linkLayerAddress);
                 break;
             default:
-                throw new RuntimeException("Unknown duidType: " + duidType.toString());
+                throw new IllegalArgumentException("Unknown duidType: " + duidType.toString());
         }
         return byteBuffer.array();
     }
@@ -171,7 +171,7 @@
                     byteBuffer.get(duid.linkLayerAddress);
                     break;
                 default:
-                    throw new RuntimeException("Unknown type: " + duidType);
+                    throw new IllegalArgumentException("Unknown type: " + duidType);
             }
             return duid;
         };
diff --git a/utils/misc/src/main/java/org/onlab/packet/dhcp/Dhcp6Option.java b/utils/misc/src/main/java/org/onlab/packet/dhcp/Dhcp6Option.java
index f19f735..8202b30 100644
--- a/utils/misc/src/main/java/org/onlab/packet/dhcp/Dhcp6Option.java
+++ b/utils/misc/src/main/java/org/onlab/packet/dhcp/Dhcp6Option.java
@@ -74,7 +74,7 @@
         try {
             this.payload = Data.deserializer().deserialize(data, 0, data.length);
         } catch (DeserializationException e) {
-            throw new RuntimeException("Invalid data");
+            throw new IllegalArgumentException("Invalid data");
         }
     }
 
diff --git a/utils/misc/src/main/java/org/onlab/util/Tools.java b/utils/misc/src/main/java/org/onlab/util/Tools.java
index bf9bea0..4b2cac9 100644
--- a/utils/misc/src/main/java/org/onlab/util/Tools.java
+++ b/utils/misc/src/main/java/org/onlab/util/Tools.java
@@ -388,7 +388,7 @@
         try {
             Thread.sleep(ms);
         } catch (InterruptedException e) {
-            throw new RuntimeException("Interrupted", e);
+            throw new IllegalStateException("Interrupted", e);
         }
     }
 
@@ -460,7 +460,7 @@
         try {
             Thread.sleep(random.nextInt(ms));
         } catch (InterruptedException e) {
-            throw new RuntimeException("Interrupted", e);
+            throw new IllegalStateException("Interrupted", e);
         }
     }
 
@@ -474,7 +474,7 @@
         try {
             Thread.sleep(ms, nanos);
         } catch (InterruptedException e) {
-            throw new RuntimeException("Interrupted", e);
+            throw new IllegalStateException("Interrupted", e);
         }
     }