8274232: Cleanup unnecessary null comparison before instanceof check …

…in jdk.jdi

Reviewed-by: cjplummer, sspitsyn

src/jdk.jdi/share/classes/com/sun/tools/example/debug/tty/Commands.java

@@ -708,9 +708,9 @@ void doKill(ThreadReference thread, StringTokenizer t) {
         }
         String expr = t.nextToken("");
         Value val = evaluate(expr);
-        if ((val != null) && (val instanceof ObjectReference)) {
+        if (val instanceof ObjectReference object) {
             try {
-                thread.stop((ObjectReference)val);
+                thread.stop(object);
                 MessageOutput.println("killed", thread.toString());
             } catch (InvalidTypeException e) {
                 MessageOutput.println("Invalid exception object");
@@ -1804,8 +1804,7 @@ void doLock(StringTokenizer t) {
         Value val = evaluate(expr);
 
         try {
-            if ((val != null) && (val instanceof ObjectReference)) {
-                ObjectReference object = (ObjectReference)val;
+            if (val instanceof ObjectReference object) {
                 String strVal = getStringValue();
                 if (strVal != null) {
                     MessageOutput.println("Monitor information for expr",
@@ -1900,8 +1899,7 @@ void doDisableGC(StringTokenizer t) {
 
         String expr = t.nextToken("");
         Value val = evaluate(expr);
-        if ((val != null) && (val instanceof ObjectReference)) {
-            ObjectReference object = (ObjectReference)val;
+        if (val instanceof ObjectReference object) {
             object.disableCollection();
             String strVal = getStringValue();
             if (strVal != null) {
@@ -1929,8 +1927,7 @@ void doEnableGC(StringTokenizer t) {
 
         String expr = t.nextToken("");
         Value val = evaluate(expr);
-        if ((val != null) && (val instanceof ObjectReference)) {
-            ObjectReference object = (ObjectReference)val;
+        if (val instanceof ObjectReference object) {
             object.enableCollection();
             String strVal = getStringValue();
             if (strVal != null) {

src/jdk.jdi/share/classes/com/sun/tools/jdi/BooleanValueImpl.java

@@ -1,5 +1,5 @@
 /*
- * Copyright (c) 1998, 2017, Oracle and/or its affiliates. All rights reserved.
+ * Copyright (c) 1998, 2021, Oracle and/or its affiliates. All rights reserved.
  * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
  *
  * This code is free software; you can redistribute it and/or modify it
@@ -40,8 +40,8 @@ public class BooleanValueImpl extends PrimitiveValueImpl
     }
 
     public boolean equals(Object obj) {
-        if ((obj != null) && (obj instanceof BooleanValue)) {
-            return (value == ((BooleanValue)obj).value()) &&
+        if (obj instanceof BooleanValue other) {
+            return (value == other.value()) &&
                    super.equals(obj);
         } else {
             return false;

src/jdk.jdi/share/classes/com/sun/tools/jdi/ByteValueImpl.java

@@ -1,5 +1,5 @@
 /*
- * Copyright (c) 1998, 2017, Oracle and/or its affiliates. All rights reserved.
+ * Copyright (c) 1998, 2021, Oracle and/or its affiliates. All rights reserved.
  * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
  *
  * This code is free software; you can redistribute it and/or modify it
@@ -41,8 +41,8 @@ public class ByteValueImpl extends PrimitiveValueImpl
     }
 
     public boolean equals(Object obj) {
-        if ((obj != null) && (obj instanceof ByteValue)) {
-            return (value == ((ByteValue)obj).value())
+        if (obj instanceof ByteValue other) {
+            return (value == other.value())
                    && super.equals(obj);
         } else {
             return false;

src/jdk.jdi/share/classes/com/sun/tools/jdi/CharValueImpl.java

@@ -1,5 +1,5 @@
 /*
- * Copyright (c) 1998, 2017, Oracle and/or its affiliates. All rights reserved.
+ * Copyright (c) 1998, 2021, Oracle and/or its affiliates. All rights reserved.
  * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
  *
  * This code is free software; you can redistribute it and/or modify it
@@ -41,8 +41,8 @@ public class CharValueImpl extends PrimitiveValueImpl
     }
 
     public boolean equals(Object obj) {
-        if ((obj != null) && (obj instanceof CharValue)) {
-            return (value == ((CharValue)obj).value()) &&
+        if (obj instanceof CharValue other) {
+            return (value == other.value()) &&
                    super.equals(obj);
         } else {
             return false;

src/jdk.jdi/share/classes/com/sun/tools/jdi/ConnectorImpl.java

@@ -192,8 +192,7 @@ public boolean mustSpecify() {
         }
 
         public boolean equals(Object obj) {
-            if ((obj != null) && (obj instanceof Connector.Argument)) {
-                Connector.Argument other = (Connector.Argument)obj;
+            if (obj instanceof Argument other) {
                 return (name().equals(other.name())) &&
                        (description().equals(other.description())) &&
                        (mustSpecify() == other.mustSpecify()) &&

src/jdk.jdi/share/classes/com/sun/tools/jdi/DoubleValueImpl.java

@@ -1,5 +1,5 @@
 /*
- * Copyright (c) 1998, 2017, Oracle and/or its affiliates. All rights reserved.
+ * Copyright (c) 1998, 2021, Oracle and/or its affiliates. All rights reserved.
  * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
  *
  * This code is free software; you can redistribute it and/or modify it
@@ -40,8 +40,8 @@ public class DoubleValueImpl extends PrimitiveValueImpl
     }
 
     public boolean equals(Object obj) {
-        if ((obj != null) && (obj instanceof DoubleValue)) {
-            return (value == ((DoubleValue)obj).value()) &&
+        if (obj instanceof DoubleValue other) {
+            return (value == other.value()) &&
                    super.equals(obj);
         } else {
             return false;

src/jdk.jdi/share/classes/com/sun/tools/jdi/FieldImpl.java

@@ -41,8 +41,7 @@ public class FieldImpl extends TypeComponentImpl
     }
 
     public boolean equals(Object obj) {
-        if ((obj != null) && (obj instanceof FieldImpl)) {
-            FieldImpl other = (FieldImpl)obj;
+        if (obj instanceof FieldImpl other) {
             return (declaringType().equals(other.declaringType())) &&
                    (ref() == other.ref()) &&
                    super.equals(obj);

src/jdk.jdi/share/classes/com/sun/tools/jdi/FloatValueImpl.java

@@ -1,5 +1,5 @@
 /*
- * Copyright (c) 1998, 2017, Oracle and/or its affiliates. All rights reserved.
+ * Copyright (c) 1998, 2021, Oracle and/or its affiliates. All rights reserved.
  * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
  *
  * This code is free software; you can redistribute it and/or modify it
@@ -40,8 +40,8 @@ public class FloatValueImpl extends PrimitiveValueImpl
     }
 
     public boolean equals(Object obj) {
-        if ((obj != null) && (obj instanceof FloatValue)) {
-            return (value == ((FloatValue)obj).value()) &&
+        if (obj instanceof FloatValue other) {
+            return (value == other.value()) &&
                    super.equals(obj);
         } else {
             return false;

src/jdk.jdi/share/classes/com/sun/tools/jdi/IntegerValueImpl.java

@@ -1,5 +1,5 @@
 /*
- * Copyright (c) 1998, 2011, Oracle and/or its affiliates. All rights reserved.
+ * Copyright (c) 1998, 2021, Oracle and/or its affiliates. All rights reserved.
  * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
  *
  * This code is free software; you can redistribute it and/or modify it
@@ -40,8 +40,8 @@ public class IntegerValueImpl extends PrimitiveValueImpl
     }
 
     public boolean equals(Object obj) {
-        if ((obj != null) && (obj instanceof IntegerValue)) {
-            return (value == ((IntegerValue)obj).value()) &&
+        if (obj instanceof IntegerValue other) {
+            return (value == other.value()) &&
                    super.equals(obj);
         } else {
             return false;

src/jdk.jdi/share/classes/com/sun/tools/jdi/LocalVariableImpl.java

@@ -1,5 +1,5 @@
 /*
- * Copyright (c) 1998, 2017, Oracle and/or its affiliates. All rights reserved.
+ * Copyright (c) 1998, 2021, Oracle and/or its affiliates. All rights reserved.
  * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
  *
  * This code is free software; you can redistribute it and/or modify it
@@ -66,8 +66,7 @@ public class LocalVariableImpl extends MirrorImpl
     }
 
     public boolean equals(Object obj) {
-        if ((obj != null) && (obj instanceof LocalVariableImpl)) {
-            LocalVariableImpl other = (LocalVariableImpl)obj;
+        if (obj instanceof LocalVariableImpl other) {
             return ((slot() == other.slot()) &&
                     (scopeStart != null) &&
                     (scopeStart.equals(other.scopeStart)) &&

src/jdk.jdi/share/classes/com/sun/tools/jdi/LocationImpl.java

@@ -1,5 +1,5 @@
 /*
- * Copyright (c) 1998, 2018, Oracle and/or its affiliates. All rights reserved.
+ * Copyright (c) 1998, 2021, Oracle and/or its affiliates. All rights reserved.
  * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
  *
  * This code is free software; you can redistribute it and/or modify it
@@ -62,8 +62,7 @@ public class LocationImpl extends MirrorImpl implements Location {
     }
 
     public boolean equals(Object obj) {
-        if ((obj != null) && (obj instanceof Location)) {
-            Location other = (Location)obj;
+        if (obj instanceof Location other) {
             return (method().equals(other.method())) &&
                    (codeIndex() == other.codeIndex()) &&
                    super.equals(obj);

src/jdk.jdi/share/classes/com/sun/tools/jdi/LongValueImpl.java

@@ -1,5 +1,5 @@
 /*
- * Copyright (c) 1998, 2017, Oracle and/or its affiliates. All rights reserved.
+ * Copyright (c) 1998, 2021, Oracle and/or its affiliates. All rights reserved.
  * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
  *
  * This code is free software; you can redistribute it and/or modify it
@@ -40,8 +40,8 @@ public class LongValueImpl extends PrimitiveValueImpl
     }
 
     public boolean equals(Object obj) {
-        if ((obj != null) && (obj instanceof LongValue)) {
-            return (value == ((LongValue)obj).value()) &&
+        if (obj instanceof LongValue other) {
+            return (value == other.value()) &&
                    super.equals(obj);
         } else {
             return false;

src/jdk.jdi/share/classes/com/sun/tools/jdi/MethodImpl.java

@@ -85,8 +85,7 @@ static MethodImpl createMethodImpl(VirtualMachine vm,
     }
 
     public boolean equals(Object obj) {
-        if ((obj != null) && (obj instanceof MethodImpl)) {
-            MethodImpl other = (MethodImpl)obj;
+        if (obj instanceof MethodImpl other) {
             return (declaringType().equals(other.declaringType())) &&
                    (ref() == other.ref()) &&
                    super.equals(obj);

src/jdk.jdi/share/classes/com/sun/tools/jdi/MirrorImpl.java

@@ -1,5 +1,5 @@
 /*
- * Copyright (c) 1998, 2018, Oracle and/or its affiliates. All rights reserved.
+ * Copyright (c) 1998, 2021, Oracle and/or its affiliates. All rights reserved.
  * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
  *
  * This code is free software; you can redistribute it and/or modify it
@@ -49,8 +49,7 @@ public VirtualMachine virtualMachine() {
     }
 
     public boolean equals(Object obj) {
-        if ((obj != null) && (obj instanceof Mirror)) {
-            Mirror other = (Mirror)obj;
+        if (obj instanceof Mirror other) {
             return vm.equals(other.virtualMachine());
         } else {
             return false;

src/jdk.jdi/share/classes/com/sun/tools/jdi/ObjectReferenceImpl.java

@@ -146,8 +146,7 @@ public boolean vmNotSuspended(VMAction action) {
     }
 
     public boolean equals(Object obj) {
-        if ((obj != null) && (obj instanceof ObjectReferenceImpl)) {
-            ObjectReferenceImpl other = (ObjectReferenceImpl)obj;
+        if (obj instanceof ObjectReferenceImpl other) {
             return (ref() == other.ref()) &&
                    super.equals(obj);
         } else {

src/jdk.jdi/share/classes/com/sun/tools/jdi/ReferenceTypeImpl.java

@@ -141,8 +141,7 @@ Field getFieldMirror(long ref) {
     }
 
     public boolean equals(Object obj) {
-        if ((obj != null) && (obj instanceof ReferenceTypeImpl)) {
-            ReferenceTypeImpl other = (ReferenceTypeImpl)obj;
+        if (obj instanceof ReferenceTypeImpl other) {
             return (ref() == other.ref()) &&
                 (vm.equals(other.virtualMachine()));
         } else {

src/jdk.jdi/share/classes/com/sun/tools/jdi/ShortValueImpl.java

@@ -1,5 +1,5 @@
 /*
- * Copyright (c) 1998, 2017, Oracle and/or its affiliates. All rights reserved.
+ * Copyright (c) 1998, 2021, Oracle and/or its affiliates. All rights reserved.
  * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
  *
  * This code is free software; you can redistribute it and/or modify it
@@ -40,8 +40,8 @@ public class ShortValueImpl extends PrimitiveValueImpl
     }
 
     public boolean equals(Object obj) {
-        if ((obj != null) && (obj instanceof ShortValue)) {
-            return (value == ((ShortValue)obj).value()) &&
+        if (obj instanceof ShortValue other) {
+            return (value == other.value()) &&
                    super.equals(obj);
         } else {
             return false;

src/jdk.jdi/share/classes/com/sun/tools/jdi/StackFrameImpl.java

@@ -1,5 +1,5 @@
 /*
- * Copyright (c) 1998, 2017, Oracle and/or its affiliates. All rights reserved.
+ * Copyright (c) 1998, 2021, Oracle and/or its affiliates. All rights reserved.
  * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
  *
  * This code is free software; you can redistribute it and/or modify it
@@ -111,8 +111,7 @@ public ThreadReference thread() {
     }
 
     public boolean equals(Object obj) {
-        if ((obj != null) && (obj instanceof StackFrameImpl)) {
-            StackFrameImpl other = (StackFrameImpl)obj;
+        if (obj instanceof StackFrameImpl other) {
             return (id == other.id) &&
                    (thread().equals(other.thread())) &&
                    (location().equals(other.location())) &&

src/jdk.jdi/share/classes/com/sun/tools/jdi/TypeImpl.java

@@ -1,5 +1,5 @@
 /*
- * Copyright (c) 1998, 2017, Oracle and/or its affiliates. All rights reserved.
+ * Copyright (c) 1998, 2021, Oracle and/or its affiliates. All rights reserved.
  * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
  *
  * This code is free software; you can redistribute it and/or modify it
@@ -46,8 +46,7 @@ public String name() {
     }
 
     public boolean equals(Object obj) {
-        if ((obj != null) && (obj instanceof Type)) {
-            Type other = (Type)obj;
+        if (obj instanceof Type other) {
             return signature().equals(other.signature()) && super.equals(obj);
         } else {
             return false;

src/jdk.jdi/share/classes/com/sun/tools/jdi/VoidValueImpl.java

@@ -1,5 +1,5 @@
 /*
- * Copyright (c) 1998, 2020, Oracle and/or its affiliates. All rights reserved.
+ * Copyright (c) 1998, 2021, Oracle and/or its affiliates. All rights reserved.
  * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
  *
  * This code is free software; you can redistribute it and/or modify it
@@ -37,7 +37,7 @@ public class VoidValueImpl extends ValueImpl implements VoidValue {
     }
 
     public boolean equals(Object obj) {
-        return (obj != null) && (obj instanceof VoidValue) && super.equals(obj);
+        return (obj instanceof VoidValue) && super.equals(obj);
     }
 
     public int hashCode() {