8317356: Fix missing null checks in the ClassFile API

Co-authored-by: Nizar Benalla <nbenalla@openjdk.org>
Reviewed-by: asotona

src/java.base/share/classes/java/lang/classfile/AnnotationValue.java

@@ -42,6 +42,8 @@ import java.util.List;
 import jdk.internal.classfile.impl.Util;
 import jdk.internal.javac.PreviewFeature;
 
+import static java.util.Objects.requireNonNull;
+
 /**
  * Models an {@code element_value} structure, or a value of an element-value
  * pair of an annotation, as defined in JVMS {@jvms 4.7.16.1}.
@@ -488,6 +490,8 @@ public sealed interface AnnotationValue {
      */
     static OfEnum ofEnum(Utf8Entry className,
                          Utf8Entry constantName) {
+        requireNonNull(className);
+        requireNonNull(constantName);
         return new AnnotationImpl.OfEnumImpl(className, constantName);
     }
 
@@ -506,6 +510,7 @@ public sealed interface AnnotationValue {
      * @param className the descriptor string of the class
      */
     static OfClass ofClass(Utf8Entry className) {
+        requireNonNull(className);
         return new AnnotationImpl.OfClassImpl(className);
     }
 
@@ -522,6 +527,7 @@ public sealed interface AnnotationValue {
      * @param value the string
      */
     static OfString ofString(Utf8Entry value) {
+        requireNonNull(value);
         return new AnnotationImpl.OfStringImpl(value);
     }
 
@@ -538,6 +544,7 @@ public sealed interface AnnotationValue {
      * @param value the double value
      */
     static OfDouble ofDouble(DoubleEntry value) {
+        requireNonNull(value);
         return new AnnotationImpl.OfDoubleImpl(value);
     }
 
@@ -554,6 +561,7 @@ public sealed interface AnnotationValue {
      * @param value the float value
      */
     static OfFloat ofFloat(FloatEntry value) {
+        requireNonNull(value);
         return new AnnotationImpl.OfFloatImpl(value);
     }
 
@@ -570,6 +578,7 @@ public sealed interface AnnotationValue {
      * @param value the long value
      */
     static OfLong ofLong(LongEntry value) {
+        requireNonNull(value);
         return new AnnotationImpl.OfLongImpl(value);
     }
 
@@ -586,6 +595,7 @@ public sealed interface AnnotationValue {
      * @param value the int value
      */
     static OfInt ofInt(IntegerEntry value) {
+        requireNonNull(value);
         return new AnnotationImpl.OfIntImpl(value);
     }
 
@@ -602,6 +612,7 @@ public sealed interface AnnotationValue {
      * @param value the short value
      */
     static OfShort ofShort(IntegerEntry value) {
+        requireNonNull(value);
         return new AnnotationImpl.OfShortImpl(value);
     }
 
@@ -618,6 +629,7 @@ public sealed interface AnnotationValue {
      * @param value the char value
      */
     static OfChar ofChar(IntegerEntry value) {
+        requireNonNull(value);
         return new AnnotationImpl.OfCharImpl(value);
     }
 
@@ -634,6 +646,7 @@ public sealed interface AnnotationValue {
      * @param value the byte value
      */
     static OfByte ofByte(IntegerEntry value) {
+        requireNonNull(value);
         return new AnnotationImpl.OfByteImpl(value);
     }
 
@@ -650,6 +663,7 @@ public sealed interface AnnotationValue {
      * @param value the boolean value
      */
     static OfBoolean ofBoolean(IntegerEntry value) {
+        requireNonNull(value);
         return new AnnotationImpl.OfBooleanImpl(value);
     }
 
@@ -667,6 +681,7 @@ public sealed interface AnnotationValue {
      * @param value the annotation
      */
     static OfAnnotation ofAnnotation(Annotation value) {
+        requireNonNull(value);
         return new AnnotationImpl.OfAnnotationImpl(value);
     }
 
@@ -784,6 +799,6 @@ public sealed interface AnnotationValue {
         } else if (value instanceof Enum<?> e) {
             return ofEnum(ClassDesc.ofDescriptor(e.getDeclaringClass().descriptorString()), e.name());
         }
-        throw new IllegalArgumentException("Illegal annotation constant value type " + (value == null ? null : value.getClass()));
+        throw new IllegalArgumentException("Illegal annotation constant value type " + requireNonNull(value).getClass());
     }
 }