Add @pure to Array.getLength()

Author: PRITI1999

src/java.base/share/classes/java/lang/reflect/Array.java

@@ -29,6 +29,7 @@
 import org.checkerframework.checker.index.qual.LengthOf;
 import org.checkerframework.checker.index.qual.NonNegative;
 import org.checkerframework.checker.interning.qual.UsesObjectEquals;
+import org.checkerframework.dataflow.qual.Pure;
 import org.checkerframework.framework.qual.AnnotatedFor;
 
 import jdk.internal.HotSpotIntrinsicCandidate;
@@ -130,7 +131,7 @@ public static Object newInstance(Class<?> componentType, @NonNegative int... dim
      * an array
      */
     @HotSpotIntrinsicCandidate
-    public static native @LengthOf({"#1"}) int getLength(Object array)
+    public static native @Pure @LengthOf({"#1"}) int getLength(Object array)
         throws IllegalArgumentException;
 
     /**