Use lambda expression to simplify statements

Change-Id: Ib8ddac6e93327ade9d42984d8eba66be7047d051
diff --git a/core/api/src/test/java/org/onosproject/net/device/DeviceServiceAdapter.java b/core/api/src/test/java/org/onosproject/net/device/DeviceServiceAdapter.java
index 795e4c0..5f52f6d 100644
--- a/core/api/src/test/java/org/onosproject/net/device/DeviceServiceAdapter.java
+++ b/core/api/src/test/java/org/onosproject/net/device/DeviceServiceAdapter.java
@@ -15,7 +15,6 @@
  */
 package org.onosproject.net.device;
 
-import com.google.common.base.Predicate;
 import com.google.common.collect.FluentIterable;
 
 import org.onosproject.net.Device;
@@ -45,13 +44,7 @@
     @Override
     public Iterable<Device> getAvailableDevices() {
         return FluentIterable.from(getDevices())
-                .filter(new Predicate<Device>() {
-
-                    @Override
-                    public boolean apply(Device input) {
-                        return isAvailable(input.id());
-                    }
-                });
+                .filter(input -> isAvailable(input.id()));
     }
 
     @Override