refactor: Annotate methods which may return null with @Nullable (#…

…115)

Use this link to re-run the recipe: https://app.moderne.io/recipes/org.openrewrite.staticanalysis.AnnotateNullableMethods?organizationId=T3BlblJld3JpdGU%3D

Co-authored-by: Moderne <team@moderne.io>

src/main/java/org/openrewrite/java/template/internal/Permit.java

@@ -21,6 +21,8 @@
  */
 package org.openrewrite.java.template.internal;
 
+import org.jspecify.annotations.Nullable;
+
 import java.lang.reflect.*;
 
 // sunapi suppresses javac's warning about using Unsafe; 'all' suppresses eclipse's warning about the unspecified 'sunapi' key. Leave them both.
@@ -77,15 +79,15 @@ public static Field getField(Class<?> c, String fName) throws NoSuchFieldExcepti
         return setAccessible(f);
     }
 
-    public static Field permissiveGetField(Class<?> c, String fName) {
+    public static @Nullable Field permissiveGetField(Class<?> c, String fName) {
         try {
             return getField(c, fName);
         } catch (Exception ignore) {
             return null;
         }
     }
 
-    public static <T> T permissiveReadField(Class<T> type, Field f, Object instance) {
+    public static <T> @Nullable T permissiveReadField(Class<T> type, Field f, Object instance) {
         try {
             return type.cast(f.get(instance));
         } catch (Exception ignore) {
@@ -147,7 +149,7 @@ public static Object invokeSneaky(Method m, Object receiver, Object... args) {
         return invokeSneaky(null, m, receiver, args);
     }
 
-    public static Object invokeSneaky(Throwable initError, Method m, Object receiver, Object... args) {
+    public static @Nullable Object invokeSneaky(Throwable initError, Method m, Object receiver, Object... args) {
         try {
             return m.invoke(receiver, args);
         } catch (NoClassDefFoundError e) {
@@ -200,7 +202,7 @@ public static <T> T newInstanceSneaky(Constructor<T> c, Object... args) {
         return newInstanceSneaky(null, c, args);
     }
 
-    public static <T> T newInstanceSneaky(Throwable initError, Constructor<T> c, Object... args) {
+    public static <T> @Nullable T newInstanceSneaky(Throwable initError, Constructor<T> c, Object... args) {
         try {
             return c.newInstance(args);
         } catch (NoClassDefFoundError e) {

src/main/java/org/openrewrite/java/template/processor/TypeAwareProcessor.java

@@ -19,6 +19,7 @@
 import com.sun.source.util.Trees;
 import com.sun.tools.javac.processing.JavacProcessingEnvironment;
 import com.sun.tools.javac.tree.JCTree;
+import org.jspecify.annotations.Nullable;
 import org.openrewrite.java.template.internal.Permit;
 import org.openrewrite.java.template.internal.permit.Parent;
 import sun.misc.Unsafe;
@@ -78,7 +79,7 @@ protected JCTree.JCCompilationUnit toUnit(Element element) {
      * This class casts the given processing environment to a JavacProcessingEnvironment. In case of
      * gradle incremental compilation, the delegate ProcessingEnvironment of the gradle wrapper is returned.
      */
-    public JavacProcessingEnvironment getJavacProcessingEnvironment(Object procEnv) {
+    public @Nullable JavacProcessingEnvironment getJavacProcessingEnvironment(Object procEnv) {
         addOpens();
         if (procEnv instanceof JavacProcessingEnvironment) {
             return (JavacProcessingEnvironment) procEnv;