Clean up code

13 files changed, 37 insertions, 60 deletions

diff --git a/node-maintainer/src/main/java/com/yahoo/vespa/hosted/node/verification/commons/noderepo/IPAddressVerifier.java b/node-maintainer/src/main/java/com/yahoo/vespa/hosted/node/verification/commons/noderepo/IPAddressVerifier.java
index 001a07ea00e..804da219140 100644
--- a/node-maintainer/src/main/java/com/yahoo/vespa/hosted/node/verification/commons/noderepo/IPAddressVerifier.java
+++ b/node-maintainer/src/main/java/com/yahoo/vespa/hosted/node/verification/commons/noderepo/IPAddressVerifier.java
@@ -50,7 +50,7 @@ public class IPAddressVerifier {
         if (!isValidIpv6(nodeSpec.getIpv6Address(), expectedHostname)) {
             faultyIpAddresses.add(nodeSpec.getIpv6Address());
         }
-        return faultyIpAddresses.stream().toArray(String[]::new);
+        return faultyIpAddresses.toArray(new String[0]);
     }
 
     private boolean isValidIpv4(String ipv4Address, String expectedHostname) {
@@ -84,9 +84,8 @@ public class IPAddressVerifier {
     protected String reverseLookUp(String ipAddress) throws NamingException {
         Hashtable<String, String> env = new Hashtable<>();
         env.put("java.naming.factory.initial", "com.sun.jndi.dns.DnsContextFactory");
-        String attributeName = ipAddress;
         DirContext ctx = new InitialDirContext(env);
-        Attributes attrs = ctx.getAttributes(attributeName, new String[]{"PTR"});
+        Attributes attrs = ctx.getAttributes(ipAddress, new String[]{"PTR"});
         for (NamingEnumeration<? extends Attribute> ae = attrs.getAll(); ae.hasMoreElements(); ) {
             Attribute attr = ae.next();
             Enumeration<?> vals = attr.getAll();
@@ -113,7 +112,7 @@ public class IPAddressVerifier {
             }
             String trailingZeroes = "0000";
             String paddedHextet = (reversedHextet + trailingZeroes).substring(0, trailingZeroes.length());
-            String punctuatedHextet = paddedHextet.replaceAll(".(?=)", "$0.");
+            String punctuatedHextet = paddedHextet.replaceAll(".", "$0.");
             newIpAddress.append(punctuatedHextet);
         }
         newIpAddress.append(domain);
diff --git a/node-maintainer/src/main/java/com/yahoo/vespa/hosted/node/verification/commons/noderepo/NodeJsonConverter.java b/node-maintainer/src/main/java/com/yahoo/vespa/hosted/node/verification/commons/noderepo/NodeJsonConverter.java
index 449f6431969..bdc4ea0789c 100644
--- a/node-maintainer/src/main/java/com/yahoo/vespa/hosted/node/verification/commons/noderepo/NodeJsonConverter.java
+++ b/node-maintainer/src/main/java/com/yahoo/vespa/hosted/node/verification/commons/noderepo/NodeJsonConverter.java
@@ -15,13 +15,13 @@ public class NodeJsonConverter {
         nodeRepoHardwareInfo.setInterfaceSpeedMbs(1000);
     }
 
-    protected static void setIpv6Interface(NodeSpec nodeSpec, HardwareInfo nodeRepoHardwareInfo) {
+    private static void setIpv6Interface(NodeSpec nodeSpec, HardwareInfo nodeRepoHardwareInfo) {
         if (nodeSpec.getIpv6Address() != null) {
             nodeRepoHardwareInfo.setIpv6Interface(true);
         }
     }
 
-    protected static void setIpv4Interface(NodeSpec nodeSpec, HardwareInfo nodeRepoHardwareInfo) {
+    private static void setIpv4Interface(NodeSpec nodeSpec, HardwareInfo nodeRepoHardwareInfo) {
         if (nodeSpec.getIpv4Address() != null) {
             nodeRepoHardwareInfo.setIpv4Interface(true);
         }
diff --git a/node-maintainer/src/main/java/com/yahoo/vespa/hosted/node/verification/commons/report/HardwareDivergenceReport.java b/node-maintainer/src/main/java/com/yahoo/vespa/hosted/node/verification/commons/report/HardwareDivergenceReport.java
index 11830c24cef..972733abdd2 100644
--- a/node-maintainer/src/main/java/com/yahoo/vespa/hosted/node/verification/commons/report/HardwareDivergenceReport.java
+++ b/node-maintainer/src/main/java/com/yahoo/vespa/hosted/node/verification/commons/report/HardwareDivergenceReport.java
@@ -38,10 +38,6 @@ public class HardwareDivergenceReport {
 
     @JsonIgnore
     public boolean isHardwareDivergenceReportEmpty() {
-        if (specVerificationReport == null && benchmarkReport == null) {
-            return true;
-        }
-        return false;
+        return specVerificationReport == null && benchmarkReport == null;
     }
-
 }
diff --git a/node-maintainer/src/main/java/com/yahoo/vespa/hosted/node/verification/hardware/benchmarks/MemoryBenchmark.java b/node-maintainer/src/main/java/com/yahoo/vespa/hosted/node/verification/hardware/benchmarks/MemoryBenchmark.java
index b701d9a02f8..dc7a41680ec 100644
--- a/node-maintainer/src/main/java/com/yahoo/vespa/hosted/node/verification/hardware/benchmarks/MemoryBenchmark.java
+++ b/node-maintainer/src/main/java/com/yahoo/vespa/hosted/node/verification/hardware/benchmarks/MemoryBenchmark.java
@@ -7,9 +7,9 @@ import com.yahoo.vespa.hosted.node.verification.commons.parser.ParseInstructions
 import com.yahoo.vespa.hosted.node.verification.commons.parser.ParseResult;
 
 import java.io.IOException;
-import java.util.ArrayList;
-import java.util.Arrays;
+import java.util.Collections;
 import java.util.List;
+import java.util.Optional;
 import java.util.logging.Level;
 import java.util.logging.Logger;
 
@@ -46,10 +46,11 @@ public class MemoryBenchmark implements Benchmark {
             setupMountPoint();
             List<String> commandOutput = commandExecutor.executeCommand(MEM_BENCHMARK_WRITE_SPEED);
             ParseResult parseResult = parseMemorySpeed(commandOutput);
-            updateMemoryWriteSpeed(parseResult.getValue());
+            parseDouble(parseResult.getValue()).ifPresent(benchmarkResults::setMemoryWriteSpeedGBs);
+
             commandOutput = commandExecutor.executeCommand(MEM_BENCHMARK_READ_SPEED);
             parseResult = parseMemorySpeed(commandOutput);
-            updateMemoryReadSpeed(parseResult.getValue());
+            parseDouble(parseResult.getValue()).ifPresent(benchmarkResults::setMemoryReadSpeedGBs);
         } catch (IOException e) {
             logger.log(Level.WARNING, "Failed to perform memory benchmark", e);
         } finally {
@@ -76,30 +77,16 @@ public class MemoryBenchmark implements Benchmark {
     }
 
     protected ParseResult parseMemorySpeed(List<String> commandOutput) {
-        List<String> searchWords = new ArrayList<>(Arrays.asList(READ_AND_WRITE_SEARCH_WORD));
+        List<String> searchWords = Collections.singletonList(READ_AND_WRITE_SEARCH_WORD);
         ParseInstructions parseInstructions = new ParseInstructions(SEARCH_ELEMENT_INDEX, RETURN_ELEMENT_INDEX, SPLIT_REGEX_STRING, searchWords);
         return OutputParser.parseSingleOutput(parseInstructions, commandOutput);
     }
 
-    protected void updateMemoryWriteSpeed(String memorySpeed) {
-        if (!isValidMemory(memorySpeed)) return;
-        double memoryWriteSpeedGbs = Double.parseDouble(memorySpeed);
-        benchmarkResults.setMemoryWriteSpeedGBs(memoryWriteSpeedGbs);
-    }
-
-    protected void updateMemoryReadSpeed(String memorySpeed) {
-        if (!isValidMemory(memorySpeed)) return;
-        double memoryReadSpeedGbs = Double.parseDouble(memorySpeed);
-        benchmarkResults.setMemoryReadSpeedGBs(memoryReadSpeedGbs);
-    }
-
-    protected boolean isValidMemory(String benchmarkOutput) {
+    private Optional<Double> parseDouble(String benchmarkOutput) {
         try {
-            Double.parseDouble(benchmarkOutput);
+            return Optional.of(Double.parseDouble(benchmarkOutput));
         } catch (NumberFormatException | NullPointerException e) {
-            return false;
+            return Optional.empty();
         }
-        return true;
     }
-
 }
diff --git a/node-maintainer/src/main/java/com/yahoo/vespa/hosted/node/verification/spec/retrievers/CPURetriever.java b/node-maintainer/src/main/java/com/yahoo/vespa/hosted/node/verification/spec/retrievers/CPURetriever.java
index b8ae5d89b55..f3ebe68a7f8 100644
--- a/node-maintainer/src/main/java/com/yahoo/vespa/hosted/node/verification/spec/retrievers/CPURetriever.java
+++ b/node-maintainer/src/main/java/com/yahoo/vespa/hosted/node/verification/spec/retrievers/CPURetriever.java
@@ -7,8 +7,7 @@ import com.yahoo.vespa.hosted.node.verification.commons.parser.ParseInstructions
 import com.yahoo.vespa.hosted.node.verification.commons.parser.ParseResult;
 
 import java.io.IOException;
-import java.util.ArrayList;
-import java.util.Arrays;
+import java.util.Collections;
 import java.util.List;
 import java.util.logging.Level;
 import java.util.logging.Logger;
@@ -47,13 +46,12 @@ public class CPURetriever implements HardwareRetriever {
     }
 
     protected List<ParseResult> parseCPUInfoFile(List<String> commandOutput) {
-        List<String> searchWords = new ArrayList<>(Arrays.asList(SEARCH_WORD));
+        List<String> searchWords = Collections.singletonList(SEARCH_WORD);
         ParseInstructions parseInstructions = new ParseInstructions(SEARCH_ELEMENT_INDEX, RETURN_ELEMENT_INDEX, REGEX_SPLIT, searchWords);
-        List<ParseResult> parseResults = OutputParser.parseOutput(parseInstructions, commandOutput);
-        return parseResults;
+        return OutputParser.parseOutput(parseInstructions, commandOutput);
     }
 
-    protected void setCpuCores(List<ParseResult> parseResults) {
+    void setCpuCores(List<ParseResult> parseResults) {
         hardwareInfo.setMinCpuCores(countCpuCores(parseResults));
     }
 
diff --git a/node-maintainer/src/main/java/com/yahoo/vespa/hosted/node/verification/spec/retrievers/DiskRetriever.java b/node-maintainer/src/main/java/com/yahoo/vespa/hosted/node/verification/spec/retrievers/DiskRetriever.java
index 8058c9438d7..810368627f2 100644
--- a/node-maintainer/src/main/java/com/yahoo/vespa/hosted/node/verification/spec/retrievers/DiskRetriever.java
+++ b/node-maintainer/src/main/java/com/yahoo/vespa/hosted/node/verification/spec/retrievers/DiskRetriever.java
@@ -8,8 +8,7 @@ import com.yahoo.vespa.hosted.node.verification.commons.parser.ParseResult;
 import com.yahoo.vespa.hosted.node.verification.spec.retrievers.HardwareInfo.DiskType;
 
 import java.io.IOException;
-import java.util.ArrayList;
-import java.util.Arrays;
+import java.util.Collections;
 import java.util.List;
 import java.util.logging.Level;
 import java.util.logging.Logger;
@@ -69,7 +68,7 @@ public class DiskRetriever implements HardwareRetriever {
     }
 
     protected ParseResult parseDiskType(List<String> commandOutput) throws IOException {
-        List<String> searchWords = new ArrayList<>(Arrays.asList(DISK_NAME));
+        List<String> searchWords = Collections.singletonList(DISK_NAME);
         ParseInstructions parseInstructions = new ParseInstructions(DISK_TYPE_SEARCH_ELEMENT_INDEX, DISK_TYPE_RETURN_ELEMENT_INDEX, DISK_TYPE_REGEX_SPLIT, searchWords);
         ParseResult parseResult = OutputParser.parseSingleOutput(parseInstructions, commandOutput);
         if (!parseResult.getSearchWord().equals(DISK_NAME)) {
@@ -90,7 +89,7 @@ public class DiskRetriever implements HardwareRetriever {
     }
 
     protected List<ParseResult> parseDiskSize(List<String> commandOutput) {
-        List<String> searchWords = new ArrayList<>(Arrays.asList(DISK_SIZE_SEARCH_WORD));
+        List<String> searchWords = Collections.singletonList(DISK_SIZE_SEARCH_WORD);
         ParseInstructions parseInstructions = new ParseInstructions(DISK_SIZE_SEARCH_ELEMENT_INDEX, DISK_SIZE_RETURN_ELEMENT_INDEX, DISK_SIZE_REGEX_SPLIT, searchWords);
         return OutputParser.parseOutput(parseInstructions, commandOutput);
     }
diff --git a/node-maintainer/src/main/java/com/yahoo/vespa/hosted/node/verification/spec/retrievers/MemoryRetriever.java b/node-maintainer/src/main/java/com/yahoo/vespa/hosted/node/verification/spec/retrievers/MemoryRetriever.java
index c6655e13797..015b274801b 100644
--- a/node-maintainer/src/main/java/com/yahoo/vespa/hosted/node/verification/spec/retrievers/MemoryRetriever.java
+++ b/node-maintainer/src/main/java/com/yahoo/vespa/hosted/node/verification/spec/retrievers/MemoryRetriever.java
@@ -7,8 +7,7 @@ import com.yahoo.vespa.hosted.node.verification.commons.parser.ParseInstructions
 import com.yahoo.vespa.hosted.node.verification.commons.parser.ParseResult;
 
 import java.io.IOException;
-import java.util.ArrayList;
-import java.util.Arrays;
+import java.util.Collections;
 import java.util.List;
 import java.util.logging.Level;
 import java.util.logging.Logger;
@@ -47,7 +46,7 @@ public class MemoryRetriever implements HardwareRetriever {
     }
 
     protected ParseResult parseMemInfoFile(List<String> commandOutput) throws IOException {
-        List<String> searchWords = new ArrayList<>(Arrays.asList(SEARCH_WORD));
+        List<String> searchWords = Collections.singletonList(SEARCH_WORD);
         ParseInstructions parseInstructions = new ParseInstructions(SEARCH_ELEMENT_INDEX, RETURN_ELEMENT_INDEX, REGEX_SPLIT, searchWords);
         ParseResult parseResult = OutputParser.parseSingleOutput(parseInstructions, commandOutput);
         if (!parseResult.getSearchWord().matches(SEARCH_WORD)) {
diff --git a/node-maintainer/src/main/java/com/yahoo/vespa/hosted/node/verification/spec/retrievers/NetRetriever.java b/node-maintainer/src/main/java/com/yahoo/vespa/hosted/node/verification/spec/retrievers/NetRetriever.java
index f30d455f339..3bea3da73fc 100644
--- a/node-maintainer/src/main/java/com/yahoo/vespa/hosted/node/verification/spec/retrievers/NetRetriever.java
+++ b/node-maintainer/src/main/java/com/yahoo/vespa/hosted/node/verification/spec/retrievers/NetRetriever.java
@@ -11,6 +11,7 @@ import org.apache.commons.exec.ExecuteException;
 import java.io.IOException;
 import java.util.ArrayList;
 import java.util.Arrays;
+import java.util.Collections;
 import java.util.List;
 import java.util.logging.Level;
 import java.util.logging.Logger;
@@ -78,8 +79,7 @@ public class NetRetriever implements HardwareRetriever {
     protected List<ParseResult> parseNetInterface(List<String> commandOutput) {
         List<String> searchWords = new ArrayList<>(Arrays.asList(SEARCH_WORD_INTERFACE_IP4, SEARCH_WORD_INTERFACE_IPV6));
         ParseInstructions parseInstructions = new ParseInstructions(INTERFACE_SEARCH_ELEMENT_INDEX, INTERFACE_RETURN_ELEMENT_INDEX, INTERFACE_NAME_REGEX_SPLIT, searchWords);
-        List<ParseResult> parseResults = OutputParser.parseOutput(parseInstructions, commandOutput);
-        return parseResults;
+        return OutputParser.parseOutput(parseInstructions, commandOutput);
     }
 
     protected void findInterfaceSpeed(List<ParseResult> parseResults) {
@@ -93,7 +93,7 @@ public class NetRetriever implements HardwareRetriever {
     }
 
     protected ParseResult parseInterfaceSpeed(List<String> commandOutput) throws IOException {
-        List<String> searchWords = new ArrayList<>(Arrays.asList(SEARCH_WORD_INTERFACE_SPEED));
+        List<String> searchWords = Collections.singletonList(SEARCH_WORD_INTERFACE_SPEED);
         ParseInstructions parseInstructions = new ParseInstructions(INTERFACE_SPEED_SEARCH_ELEMENT_INDEX, INTERFACE_SPEED_RETURN_ELEMENT_INDEX, INTERFACE_SPEED_REGEX_SPLIT, searchWords);
         ParseResult parseResult = OutputParser.parseSingleOutput(parseInstructions, commandOutput);
         if (!parseResult.getSearchWord().matches(SEARCH_WORD_INTERFACE_SPEED)) {
@@ -114,7 +114,7 @@ public class NetRetriever implements HardwareRetriever {
     }
 
     protected ParseResult parsePingResponse(List<String> commandOutput) throws IOException {
-        List<String> searchWords = new ArrayList<>(Arrays.asList(PING_SEARCH_WORD));
+        List<String> searchWords = Collections.singletonList(PING_SEARCH_WORD);
         ParseInstructions parseInstructions = new ParseInstructions(PING_SEARCH_ELEMENT_INDEX, PING_RETURN_ELEMENT_INDEX, PING_SPLIT_REGEX_STRING, searchWords);
         ParseResult parseResult = OutputParser.parseSingleOutput(parseInstructions, commandOutput);
         if (!parseResult.getSearchWord().matches(PING_SEARCH_WORD)) {
diff --git a/node-maintainer/src/test/java/com/yahoo/vespa/hosted/node/maintainer/CoreCollectorTest.java b/node-maintainer/src/test/java/com/yahoo/vespa/hosted/node/maintainer/CoreCollectorTest.java
index 6e308e0201e..869b53dc7a7 100644
--- a/node-maintainer/src/test/java/com/yahoo/vespa/hosted/node/maintainer/CoreCollectorTest.java
+++ b/node-maintainer/src/test/java/com/yahoo/vespa/hosted/node/maintainer/CoreCollectorTest.java
@@ -58,7 +58,7 @@ public class CoreCollectorTest {
     }
 
     private void mockExec(String[] cmd, String output, String error) throws IOException, InterruptedException {
-        when(processExecuter.exec(cmd)).thenReturn(new Pair<Integer, String>(error.isEmpty() ? 0 : 1, output + error));
+        when(processExecuter.exec(cmd)).thenReturn(new Pair<>(error.isEmpty() ? 0 : 1, output + error));
     }
 
     static final String GDB_PATH = getDefaults().underVespaHome("bin64/gdb");
diff --git a/node-maintainer/src/test/java/com/yahoo/vespa/hosted/node/verification/commons/parser/OutputParserTest.java b/node-maintainer/src/test/java/com/yahoo/vespa/hosted/node/verification/commons/parser/OutputParserTest.java
index 09286f4e61a..060b899c099 100644
--- a/node-maintainer/src/test/java/com/yahoo/vespa/hosted/node/verification/commons/parser/OutputParserTest.java
+++ b/node-maintainer/src/test/java/com/yahoo/vespa/hosted/node/verification/commons/parser/OutputParserTest.java
@@ -6,6 +6,7 @@ import org.junit.Test;
 
 import java.util.ArrayList;
 import java.util.Arrays;
+import java.util.Collections;
 import java.util.List;
 
 import static org.junit.Assert.assertEquals;
@@ -56,7 +57,7 @@ public class OutputParserTest {
 
     @Test
     public void parseOutput_searching_for_word_containing_capital_s() {
-        searchWords = new ArrayList<>(Arrays.asList(REGEX_SEARCH_WORD));
+        searchWords = Collections.singletonList(REGEX_SEARCH_WORD);
         ParseInstructions parseInstructions = new ParseInstructions(1, 8, " ", searchWords);
         List<ParseResult> parseResults = OutputParser.parseOutput(parseInstructions, commandOutput);
         ParseResult expectedParseResult1 = new ParseResult("Should", RETURN_VALUE);
@@ -67,7 +68,7 @@ public class OutputParserTest {
 
     @Test
     public void parseSingleOutput_should_return_first_match() {
-        searchWords = new ArrayList<>(Arrays.asList(SEARCH_WORD_1));
+        searchWords = Collections.singletonList(SEARCH_WORD_1);
         ParseInstructions parseInstructions = new ParseInstructions(6, 8, " ", searchWords);
         ParseResult parseResult = OutputParser.parseSingleOutput(parseInstructions, commandOutput);
         ParseResult expectedParseResult = new ParseResult(SEARCH_WORD_1, RETURN_VALUE);
@@ -76,7 +77,7 @@ public class OutputParserTest {
 
     @Test
     public void parseSingleOutput_should_return_invalid_parseResult() {
-        searchWords = new ArrayList<>(Arrays.asList("No match"));
+        searchWords = Collections.singletonList("No match");
         ParseInstructions parseInstructions = new ParseInstructions(6, 8, " ", searchWords);
         ParseResult parseResult = OutputParser.parseSingleOutput(parseInstructions, commandOutput);
         ParseResult expectedParseResult = new ParseResult("invalid", "invalid");
diff --git a/node-maintainer/src/test/java/com/yahoo/vespa/hosted/node/verification/hardware/benchmarks/DiskBenchmarkTest.java b/node-maintainer/src/test/java/com/yahoo/vespa/hosted/node/verification/hardware/benchmarks/DiskBenchmarkTest.java
index 8254718f36d..9bf23645316 100644
--- a/node-maintainer/src/test/java/com/yahoo/vespa/hosted/node/verification/hardware/benchmarks/DiskBenchmarkTest.java
+++ b/node-maintainer/src/test/java/com/yahoo/vespa/hosted/node/verification/hardware/benchmarks/DiskBenchmarkTest.java
@@ -6,7 +6,6 @@ import com.yahoo.vespa.hosted.node.verification.mock.MockCommandExecutor;
 import org.junit.Before;
 import org.junit.Test;
 
-import java.util.ArrayList;
 import java.util.List;
 
 import static org.junit.Assert.assertEquals;
diff --git a/node-maintainer/src/test/java/com/yahoo/vespa/hosted/node/verification/spec/retrievers/DiskRetrieverTest.java b/node-maintainer/src/test/java/com/yahoo/vespa/hosted/node/verification/spec/retrievers/DiskRetrieverTest.java
index f6969e4ac6f..220d89f3be9 100644
--- a/node-maintainer/src/test/java/com/yahoo/vespa/hosted/node/verification/spec/retrievers/DiskRetrieverTest.java
+++ b/node-maintainer/src/test/java/com/yahoo/vespa/hosted/node/verification/spec/retrievers/DiskRetrieverTest.java
@@ -79,7 +79,7 @@ public class DiskRetrieverTest {
     public void parseDiskType_with_invalid_outputstream_does_not_contain_searchword_should_throw_exception() throws Exception {
         List<String> mockOutput = commandExecutor.outputFromString("Name  Rota");
         try {
-            ParseResult parseResult = diskRetriever.parseDiskType(mockOutput);
+            diskRetriever.parseDiskType(mockOutput);
             fail("Should have thrown IOException when outputstream doesn't contain search word");
         } catch (IOException e) {
             String expectedExceptionMessage = "Parsing for disk type failed";
diff --git a/node-maintainer/src/test/java/com/yahoo/vespa/hosted/node/verification/spec/retrievers/NetRetrieverTest.java b/node-maintainer/src/test/java/com/yahoo/vespa/hosted/node/verification/spec/retrievers/NetRetrieverTest.java
index 565712608f5..eb9f122b726 100644
--- a/node-maintainer/src/test/java/com/yahoo/vespa/hosted/node/verification/spec/retrievers/NetRetrieverTest.java
+++ b/node-maintainer/src/test/java/com/yahoo/vespa/hosted/node/verification/spec/retrievers/NetRetrieverTest.java
@@ -9,7 +9,7 @@ import org.junit.Test;
 
 import java.io.IOException;
 import java.util.ArrayList;
-import java.util.Arrays;
+import java.util.Collections;
 import java.util.List;
 
 import static org.junit.Assert.assertEquals;
@@ -84,8 +84,7 @@ public class NetRetrieverTest {
     public void parseNetInterface_get_ipv_from_ifconfigNotIpv6_testFile() throws IOException {
         List<String> mockOutput = MockCommandExecutor.readFromFile(NET_FIND_INTERFACE + "NoIpv6");
         parseResults = net.parseNetInterface(mockOutput);
-        ArrayList<ParseResult> expextedParseResults = new ArrayList<>(Arrays.asList(
-                new ParseResult("inet", "inet")));
+        List<ParseResult> expextedParseResults = Collections.singletonList(new ParseResult("inet", "inet"));
         assertEquals(expextedParseResults, parseResults);
     }
 
@@ -130,7 +129,7 @@ public class NetRetrieverTest {
     public void parsePingResponse_invalid_ping_response_should_throw_IOException() throws IOException {
         List<String> mockCommandOutput = MockCommandExecutor.readFromFile(INVALID_PING_RESPONSE);
         try {
-            ParseResult parseResult = net.parsePingResponse(mockCommandOutput);
+            net.parsePingResponse(mockCommandOutput);
             fail("Expected an IOException to be thrown");
         } catch (IOException e) {
             String expectedExceptionMessage = "Failed to parse ping output.";