diff --git a/com.microsoft.java.debug.core/src/main/java/com/microsoft/java/debug/core/AsyncJdwpUtils.java b/com.microsoft.java.debug.core/src/main/java/com/microsoft/java/debug/core/AsyncJdwpUtils.java
index fad2ac223..7f984a809 100644
--- a/com.microsoft.java.debug.core/src/main/java/com/microsoft/java/debug/core/AsyncJdwpUtils.java
+++ b/com.microsoft.java.debug.core/src/main/java/com/microsoft/java/debug/core/AsyncJdwpUtils.java
@@ -23,6 +23,7 @@
 import java.util.function.Supplier;
 
 public class AsyncJdwpUtils {
+    private AsyncJdwpUtils(){}
     /**
      * Create a the thread pool to process JDWP tasks.
      * JDWP tasks are IO-bounded, so use a relatively large thread pool for JDWP tasks.
diff --git a/com.microsoft.java.debug.core/src/main/java/com/microsoft/java/debug/core/Configuration.java b/com.microsoft.java.debug.core/src/main/java/com/microsoft/java/debug/core/Configuration.java
index 6e6b34064..706d0f30c 100644
--- a/com.microsoft.java.debug.core/src/main/java/com/microsoft/java/debug/core/Configuration.java
+++ b/com.microsoft.java.debug.core/src/main/java/com/microsoft/java/debug/core/Configuration.java
@@ -12,6 +12,7 @@
 package com.microsoft.java.debug.core;
 
 public class Configuration {
+    private Configuration(){}
     public static final String LOGGER_NAME = "java-debug";
     public static final String USAGE_DATA_LOGGER_NAME = "java-debug-usage-data";
 
diff --git a/com.microsoft.java.debug.core/src/main/java/com/microsoft/java/debug/core/DebugSession.java b/com.microsoft.java.debug.core/src/main/java/com/microsoft/java/debug/core/DebugSession.java
index fbad52fe2..989f47883 100644
--- a/com.microsoft.java.debug.core/src/main/java/com/microsoft/java/debug/core/DebugSession.java
+++ b/com.microsoft.java.debug.core/src/main/java/com/microsoft/java/debug/core/DebugSession.java
@@ -161,9 +161,7 @@ public void setExceptionBreakpoints(boolean notifyCaught, boolean notifyUncaught
         } catch (VMDisconnectedException ex) {
             // ignore since removing breakpoints is meaningless when JVM is terminated.
         }
-        subscriptions.forEach(subscription -> {
-            subscription.dispose();
-        });
+        subscriptions.forEach(Disposable::dispose);
         subscriptions.clear();
         eventRequests.clear();
 
diff --git a/com.microsoft.java.debug.core/src/main/java/com/microsoft/java/debug/core/StackFrameUtility.java b/com.microsoft.java.debug.core/src/main/java/com/microsoft/java/debug/core/StackFrameUtility.java
index 3195747f3..d67011059 100644
--- a/com.microsoft.java.debug.core/src/main/java/com/microsoft/java/debug/core/StackFrameUtility.java
+++ b/com.microsoft.java.debug.core/src/main/java/com/microsoft/java/debug/core/StackFrameUtility.java
@@ -19,7 +19,7 @@
 import com.sun.jdi.StackFrame;
 
 public final class StackFrameUtility {
-
+    private StackFrameUtility(){}
     public static boolean isNative(StackFrame frame) {
         return frame.location().method().isNative();
     }
diff --git a/com.microsoft.java.debug.core/src/main/java/com/microsoft/java/debug/core/Watchpoint.java b/com.microsoft.java.debug.core/src/main/java/com/microsoft/java/debug/core/Watchpoint.java
index 3de321ec8..9db53e9eb 100644
--- a/com.microsoft.java.debug.core/src/main/java/com/microsoft/java/debug/core/Watchpoint.java
+++ b/com.microsoft.java.debug.core/src/main/java/com/microsoft/java/debug/core/Watchpoint.java
@@ -90,9 +90,7 @@ public void close() throws Exception {
         } catch (VMDisconnectedException ex) {
             // ignore since removing breakpoints is meaningless when JVM is terminated.
         }
-        subscriptions().forEach(subscription -> {
-            subscription.dispose();
-        });
+        subscriptions().forEach(Disposable::dispose);
         requests.clear();
         subscriptions.clear();
     }
@@ -134,7 +132,7 @@ public void setHitCount(int hitCount) {
         this.hitCount = hitCount;
 
         Observable.fromIterable(this.requests())
-            .filter(request -> request instanceof WatchpointRequest)
+            .filter(WatchpointRequest.class::isInstance)
             .subscribe(request -> {
                 request.addCountFilter(hitCount);
                 request.enable();
diff --git a/com.microsoft.java.debug.core/src/main/java/com/microsoft/java/debug/core/adapter/AdapterUtils.java b/com.microsoft.java.debug.core/src/main/java/com/microsoft/java/debug/core/adapter/AdapterUtils.java
index c30aa8742..9d7635188 100644
--- a/com.microsoft.java.debug.core/src/main/java/com/microsoft/java/debug/core/adapter/AdapterUtils.java
+++ b/com.microsoft.java.debug.core/src/main/java/com/microsoft/java/debug/core/adapter/AdapterUtils.java
@@ -38,6 +38,7 @@
 import com.microsoft.java.debug.core.protocol.Types;
 
 public class AdapterUtils {
+    private AdapterUtils(){}
     private static final String OS_NAME = System.getProperty("os.name", "").toLowerCase();
     private static final Pattern ENCLOSING_CLASS_REGEX = Pattern.compile("^([^\\$]*)");
     public static final boolean isWin = isWindows();
@@ -288,7 +289,7 @@ public static String getSHA256HexDigest(String content) {
         } catch (NoSuchAlgorithmException e) {
             // ignore it.
         }
-        StringBuffer buf = new StringBuffer();
+        StringBuilder buf = new StringBuilder();
         if (hashBytes != null) {
             for (byte b : hashBytes) {
                 buf.append(Integer.toHexString((b & 0xFF) + 0x100).substring(1));
diff --git a/com.microsoft.java.debug.core/src/main/java/com/microsoft/java/debug/core/adapter/BreakpointManager.java b/com.microsoft.java.debug.core/src/main/java/com/microsoft/java/debug/core/adapter/BreakpointManager.java
index eaf1bb56f..cbc6c09cc 100644
--- a/com.microsoft.java.debug.core/src/main/java/com/microsoft/java/debug/core/adapter/BreakpointManager.java
+++ b/com.microsoft.java.debug.core/src/main/java/com/microsoft/java/debug/core/adapter/BreakpointManager.java
@@ -209,7 +209,7 @@ private String getWatchpointKey(IWatchpoint watchpoint) {
 
     @Override
     public IWatchpoint[] getWatchpoints() {
-        return this.watchpoints.values().stream().filter(wp -> wp != null).toArray(IWatchpoint[]::new);
+        return this.watchpoints.values().stream().filter(Objects::nonNull).toArray(IWatchpoint[]::new);
     }
 
     @Override
diff --git a/com.microsoft.java.debug.core/src/main/java/com/microsoft/java/debug/core/adapter/Constants.java b/com.microsoft.java.debug.core/src/main/java/com/microsoft/java/debug/core/adapter/Constants.java
index 2e523aba2..8035cb3b1 100644
--- a/com.microsoft.java.debug.core/src/main/java/com/microsoft/java/debug/core/adapter/Constants.java
+++ b/com.microsoft.java.debug.core/src/main/java/com/microsoft/java/debug/core/adapter/Constants.java
@@ -12,6 +12,7 @@
 package com.microsoft.java.debug.core.adapter;
 
 public final class Constants {
+    private Constants(){}
     public static final String PROJECT_NAME = "projectName";
     public static final String DEBUGGEE_ENCODING = "debuggeeEncoding";
     public static final String MAIN_CLASS = "mainClass";
diff --git a/com.microsoft.java.debug.core/src/main/java/com/microsoft/java/debug/core/adapter/DebugAdapter.java b/com.microsoft.java.debug.core/src/main/java/com/microsoft/java/debug/core/adapter/DebugAdapter.java
index 8f595151f..321f5bc27 100644
--- a/com.microsoft.java.debug.core/src/main/java/com/microsoft/java/debug/core/adapter/DebugAdapter.java
+++ b/com.microsoft.java.debug.core/src/main/java/com/microsoft/java/debug/core/adapter/DebugAdapter.java
@@ -90,9 +90,7 @@ public CompletableFuture<Messages.Response> dispatchRequest(Messages.Request req
         if (handlers != null && !handlers.isEmpty()) {
             CompletableFuture<Messages.Response> future = CompletableFuture.completedFuture(response);
             for (IDebugRequestHandler handler : handlers) {
-                future = future.thenCompose((res) -> {
-                    return handler.handle(command, cmdArgs, res, debugContext);
-                });
+                future = future.thenCompose(res -> handler.handle(command, cmdArgs, res, debugContext));
             }
             return future;
         } else {
diff --git a/com.microsoft.java.debug.core/src/main/java/com/microsoft/java/debug/core/adapter/ErrorCode.java b/com.microsoft.java.debug.core/src/main/java/com/microsoft/java/debug/core/adapter/ErrorCode.java
index 6cfe523cf..888424faa 100644
--- a/com.microsoft.java.debug.core/src/main/java/com/microsoft/java/debug/core/adapter/ErrorCode.java
+++ b/com.microsoft.java.debug.core/src/main/java/com/microsoft/java/debug/core/adapter/ErrorCode.java
@@ -56,9 +56,7 @@ public int getId() {
      * @return the ErrorCode type.
      */
     public static ErrorCode parse(int id) {
-        ErrorCode[] found = Arrays.stream(ErrorCode.values()).filter(code -> {
-            return code.getId() == id;
-        }).toArray(ErrorCode[]::new);
+        ErrorCode[] found = Arrays.stream(ErrorCode.values()).filter(code -> code.getId() == id).toArray(ErrorCode[]::new);
 
         if (found.length > 0) {
             return found[0];
diff --git a/com.microsoft.java.debug.core/src/main/java/com/microsoft/java/debug/core/adapter/ProcessConsole.java b/com.microsoft.java.debug.core/src/main/java/com/microsoft/java/debug/core/adapter/ProcessConsole.java
index 3d823df91..a94502e58 100644
--- a/com.microsoft.java.debug.core/src/main/java/com/microsoft/java/debug/core/adapter/ProcessConsole.java
+++ b/com.microsoft.java.debug.core/src/main/java/com/microsoft/java/debug/core/adapter/ProcessConsole.java
@@ -86,7 +86,7 @@ public Observable<ConsoleMessage> lineMessages() {
         return this.messages().map((message) -> {
             String[] lines = message.output.split("(?<=\n)");
             return Stream.of(lines).map((line) -> new ConsoleMessage(line, message.category)).toArray(ConsoleMessage[]::new);
-        }).concatMap((lines) -> Observable.fromArray(lines));
+        }).concatMap(Observable::fromArray);
     }
 
     public static class InputStreamObservable {
diff --git a/com.microsoft.java.debug.core/src/main/java/com/microsoft/java/debug/core/adapter/formatter/TypeIdentifiers.java b/com.microsoft.java.debug.core/src/main/java/com/microsoft/java/debug/core/adapter/formatter/TypeIdentifiers.java
index 611c9d2d3..ddff22c98 100644
--- a/com.microsoft.java.debug.core/src/main/java/com/microsoft/java/debug/core/adapter/formatter/TypeIdentifiers.java
+++ b/com.microsoft.java.debug.core/src/main/java/com/microsoft/java/debug/core/adapter/formatter/TypeIdentifiers.java
@@ -12,6 +12,7 @@
 package com.microsoft.java.debug.core.adapter.formatter;
 
 public final class TypeIdentifiers {
+    private TypeIdentifiers(){}
     public static final char ARRAY = '[';
     public static final char BYTE = 'B';
     public static final char CHAR = 'C';
diff --git a/com.microsoft.java.debug.core/src/main/java/com/microsoft/java/debug/core/adapter/handler/ExceptionInfoRequestHandler.java b/com.microsoft.java.debug.core/src/main/java/com/microsoft/java/debug/core/adapter/handler/ExceptionInfoRequestHandler.java
index 5e065edd0..807731477 100644
--- a/com.microsoft.java.debug.core/src/main/java/com/microsoft/java/debug/core/adapter/handler/ExceptionInfoRequestHandler.java
+++ b/com.microsoft.java.debug.core/src/main/java/com/microsoft/java/debug/core/adapter/handler/ExceptionInfoRequestHandler.java
@@ -79,7 +79,7 @@ public CompletableFuture<Response> handle(Command command, Arguments arguments,
         String exceptionToString = typeName;
         if (toStringMethod != null) {
             try {
-                Value returnValue = jdiException.exception.invokeMethod(thread, toStringMethod, Collections.EMPTY_LIST, ObjectReference.INVOKE_SINGLE_THREADED);
+                Value returnValue = jdiException.exception.invokeMethod(thread, toStringMethod, Collections.emptyList(), ObjectReference.INVOKE_SINGLE_THREADED);
                 exceptionToString = returnValue.toString();
             } catch (InvalidTypeException | ClassNotLoadedException | IncompatibleThreadStateException
                     | InvocationException e) {
diff --git a/com.microsoft.java.debug.core/src/main/java/com/microsoft/java/debug/core/adapter/handler/LaunchRequestHandler.java b/com.microsoft.java.debug.core/src/main/java/com/microsoft/java/debug/core/adapter/handler/LaunchRequestHandler.java
index e5662f936..ca45e37ea 100644
--- a/com.microsoft.java.debug.core/src/main/java/com/microsoft/java/debug/core/adapter/handler/LaunchRequestHandler.java
+++ b/com.microsoft.java.debug.core/src/main/java/com/microsoft/java/debug/core/adapter/handler/LaunchRequestHandler.java
@@ -66,7 +66,7 @@
 
 public class LaunchRequestHandler implements IDebugRequestHandler {
     protected static final Logger logger = Logger.getLogger(Configuration.LOGGER_NAME);
-    protected static final long RUNINTERMINAL_TIMEOUT = 10 * 1000;
+
     protected ILaunchDelegate activeLaunchHandler;
     private CompletableFuture<Boolean> waitForDebuggeeConsole = new CompletableFuture<>();
 
diff --git a/com.microsoft.java.debug.core/src/main/java/com/microsoft/java/debug/core/adapter/handler/LaunchUtils.java b/com.microsoft.java.debug.core/src/main/java/com/microsoft/java/debug/core/adapter/handler/LaunchUtils.java
index 27fdb1813..68ed9717c 100644
--- a/com.microsoft.java.debug.core/src/main/java/com/microsoft/java/debug/core/adapter/handler/LaunchUtils.java
+++ b/com.microsoft.java.debug.core/src/main/java/com/microsoft/java/debug/core/adapter/handler/LaunchUtils.java
@@ -45,6 +45,7 @@
 import com.microsoft.java.debug.core.adapter.AdapterUtils;
 
 public class LaunchUtils {
+    private LaunchUtils(){}
     private static final Logger logger = Logger.getLogger(Configuration.LOGGER_NAME);
     private static Set<Path> tempFilesInUse = new HashSet<>();
     private static final Charset SYSTEM_CHARSET;
@@ -262,7 +263,7 @@ private static long findJavaProcessByCygwinPsCommand(ProcessHandle shellProcess,
         }
 
         if (!javaCandidates.isEmpty()) {
-            Set<Long> descendantWinpids = shellProcess.descendants().map(proc -> proc.pid()).collect(Collectors.toSet());
+            Set<Long> descendantWinpids = shellProcess.descendants().map(ProcessHandle::pid).collect(Collectors.toSet());
             long shellWinpid = shellProcess.pid();
             for (PsProcess javaCandidate: javaCandidates) {
                 if (descendantWinpids.contains(javaCandidate.winpid)) {
diff --git a/com.microsoft.java.debug.core/src/main/java/com/microsoft/java/debug/core/adapter/handler/SetBreakpointsRequestHandler.java b/com.microsoft.java.debug.core/src/main/java/com/microsoft/java/debug/core/adapter/handler/SetBreakpointsRequestHandler.java
index 09dafd1b0..78dbad68c 100644
--- a/com.microsoft.java.debug.core/src/main/java/com/microsoft/java/debug/core/adapter/handler/SetBreakpointsRequestHandler.java
+++ b/com.microsoft.java.debug.core/src/main/java/com/microsoft/java/debug/core/adapter/handler/SetBreakpointsRequestHandler.java
@@ -187,7 +187,7 @@ private void registerBreakpointHandler(IDebugAdapterContext context) {
         if (debugSession != null) {
             debugSession.getEventHub().events().filter(debugEvent -> debugEvent.event instanceof BreakpointEvent).subscribe(debugEvent -> {
                 Event event = debugEvent.event;
-                if (debugEvent.eventSet.size() > 1 && debugEvent.eventSet.stream().anyMatch(t -> t instanceof StepEvent)) {
+                if (debugEvent.eventSet.size() > 1 && debugEvent.eventSet.stream().anyMatch(StepEvent.class::isInstance)) {
                     // The StepEvent and BreakpointEvent are grouped in the same event set only if they occurs at the same location and in the same thread.
                     // In order to avoid two duplicated StoppedEvents, the debugger will skip the BreakpointEvent.
                 } else {
diff --git a/com.microsoft.java.debug.core/src/main/java/com/microsoft/java/debug/core/adapter/variables/JavaLogicalStructureManager.java b/com.microsoft.java.debug.core/src/main/java/com/microsoft/java/debug/core/adapter/variables/JavaLogicalStructureManager.java
index 2762173cd..45f126c16 100644
--- a/com.microsoft.java.debug.core/src/main/java/com/microsoft/java/debug/core/adapter/variables/JavaLogicalStructureManager.java
+++ b/com.microsoft.java.debug.core/src/main/java/com/microsoft/java/debug/core/adapter/variables/JavaLogicalStructureManager.java
@@ -26,6 +26,7 @@
 import com.sun.jdi.Value;
 
 public class JavaLogicalStructureManager {
+    private JavaLogicalStructureManager(){}
     private static final List<JavaLogicalStructure> supportedLogicalStructures = Collections.synchronizedList(new ArrayList<>());
 
     static {
diff --git a/com.microsoft.java.debug.core/src/main/java/com/microsoft/java/debug/core/adapter/variables/VariableUtils.java b/com.microsoft.java.debug.core/src/main/java/com/microsoft/java/debug/core/adapter/variables/VariableUtils.java
index 1a8139fa9..3218f636e 100644
--- a/com.microsoft.java.debug.core/src/main/java/com/microsoft/java/debug/core/adapter/variables/VariableUtils.java
+++ b/com.microsoft.java.debug.core/src/main/java/com/microsoft/java/debug/core/adapter/variables/VariableUtils.java
@@ -62,7 +62,7 @@ public abstract class VariableUtils {
      * @return true if this value is reference objects.
      */
     public static boolean hasChildren(Value value, boolean includeStatic) {
-        if (value == null || !(value instanceof ObjectReference)) {
+        if (!(value instanceof ObjectReference)) {
             return false;
         }
         ReferenceType type = ((ObjectReference) value).referenceType();
@@ -189,7 +189,7 @@ public static List<Variable> listLocalVariables(StackFrame stackFrame) throws Ab
             // avoid listing variable on native methods
 
             try {
-                if (stackFrame.location().method().argumentTypes().size() == 0) {
+                if (stackFrame.location().method().argumentTypes().isEmpty()) {
                     return res;
                 }
             } catch (ClassNotLoadedException ex2) {