Record like property access support

src/main/java/graphql/schema/PropertyDataFetcher.java

@@ -8,20 +8,20 @@
 import java.util.function.Function;
 
 /**
- * This is the default data fetcher used in graphql-java.  It will examine
- * maps and POJO java beans for values that match the desired name, typically the field name
+ * This is the default data fetcher used in graphql-java, and it will examine
+ * maps, records and POJO java beans for values that match the desired name, typically the field name,
  * or it will use a provided function to obtain values.
- * maps and POJO java beans for values that match the desired name.
  * <p>
  * It uses the following strategies
  * <ul>
  * <li>If the source is null, return null</li>
  * <li>If the source is a Map, return map.get(propertyName)</li>
  * <li>If a function is provided, it is used</li>
- * <li>Find a public JavaBean getter method named `propertyName`</li>
- * <li>Find any getter method named `propertyName` and call method.setAccessible(true)</li>
+ * <li>Find a public JavaBean getter method named `getPropertyName()` or `isPropertyName()`</li>
+ * <li>Find any getter method named `getPropertyName()` or `isPropertyName()` and call method.setAccessible(true)</li>
  * <li>Find a public field named `propertyName`</li>
  * <li>Find any field named `propertyName` and call field.setAccessible(true)</li>
+ * <li>Find a public Record like method named `propertyName()`</li>
  * <li>If this cant find anything, then null is returned</li>
  * </ul>
  * <p>

src/main/java/graphql/schema/PropertyDataFetcherHelper.java

@@ -1,6 +1,7 @@
 package graphql.schema;
 
 import graphql.Internal;
+import graphql.VisibleForTesting;
 
 /**
  * This class is the guts of a property data fetcher and also used in AST code to turn
@@ -27,6 +28,11 @@ public static boolean setUseSetAccessible(boolean flag) {
         return impl.setUseSetAccessible(flag);
     }
 
+    @VisibleForTesting
+    public static boolean setUseLambdaFactory(boolean flag) {
+        return impl.setUseLambdaFactory(flag);
+    }
+
     public static boolean setUseNegativeCache(boolean flag) {
         return impl.setUseNegativeCache(flag);
     }

src/main/java/graphql/schema/PropertyFetchingImpl.java

@@ -31,6 +31,7 @@
 public class PropertyFetchingImpl {
 
     private final AtomicBoolean USE_SET_ACCESSIBLE = new AtomicBoolean(true);
+    private final AtomicBoolean USE_LAMBDA_FACTORY = new AtomicBoolean(true);
     private final AtomicBoolean USE_NEGATIVE_CACHE = new AtomicBoolean(true);
     private final ConcurrentMap<CacheKey, CachedLambdaFunction> LAMBDA_CACHE = new ConcurrentHashMap<>();
     private final ConcurrentMap<CacheKey, CachedMethod> METHOD_CACHE = new ConcurrentHashMap<>();
@@ -104,7 +105,7 @@ public Object getPropertyValue(String propertyName, Object object, GraphQLType g
         // expensive operation here
         //
 
-        Optional<Function<Object, Object>> getterOpt = LambdaFetchingSupport.createGetter(object.getClass(), propertyName);
+        Optional<Function<Object, Object>> getterOpt = lambdaGetter(propertyName, object);
         if (getterOpt.isPresent()) {
             Function<Object, Object> getter = getterOpt.get();
             cachedFunction = new CachedLambdaFunction(getter);
@@ -113,23 +114,43 @@ public Object getPropertyValue(String propertyName, Object object, GraphQLType g
         }
 
         boolean dfeInUse = singleArgumentValue != null;
+        //
+        // try by record like name - object.propertyName()
+        try {
+            MethodFinder methodFinder = (rootClass, methodName) -> findRecordMethod(cacheKey, rootClass, methodName);
+            return getPropertyViaRecordMethod(object, propertyName, methodFinder, singleArgumentValue);
+        } catch (NoSuchMethodException ignored) {
+        }
+        //
+        // try by public getters name -  object.getPropertyName()
         try {
-            MethodFinder methodFinder = (root, methodName) -> findPubliclyAccessibleMethod(cacheKey, root, methodName, dfeInUse);
+            MethodFinder methodFinder = (rootClass, methodName) -> findPubliclyAccessibleMethod(cacheKey, rootClass, methodName, dfeInUse);
+            return getPropertyViaGetterMethod(object, propertyName, graphQLType, methodFinder, singleArgumentValue);
+        } catch (NoSuchMethodException ignored) {
+        }
+        //
+        // try by accessible getters name -  object.getPropertyName()
+        try {
+            MethodFinder methodFinder = (aClass, methodName) -> findViaSetAccessible(cacheKey, aClass, methodName, dfeInUse);
             return getPropertyViaGetterMethod(object, propertyName, graphQLType, methodFinder, singleArgumentValue);
         } catch (NoSuchMethodException ignored) {
-            try {
-                MethodFinder methodFinder = (aClass, methodName) -> findViaSetAccessible(cacheKey, aClass, methodName, dfeInUse);
-                return getPropertyViaGetterMethod(object, propertyName, graphQLType, methodFinder, singleArgumentValue);
-            } catch (NoSuchMethodException ignored2) {
-                try {
-                    return getPropertyViaFieldAccess(cacheKey, object, propertyName);
-                } catch (FastNoSuchMethodException e) {
-                    // we have nothing to ask for, and we have exhausted our lookup strategies
-                    putInNegativeCache(cacheKey);
-                    return null;
-                }
-            }
         }
+        //
+        // try by field name -  object.propertyName;
+        try {
+            return getPropertyViaFieldAccess(cacheKey, object, propertyName);
+        } catch (NoSuchMethodException ignored) {
+        }
+        // we have nothing to ask for, and we have exhausted our lookup strategies
+        putInNegativeCache(cacheKey);
+        return null;
+    }
+
+    private Optional<Function<Object, Object>> lambdaGetter(String propertyName, Object object) {
+        if (USE_LAMBDA_FACTORY.get()) {
+            return LambdaFetchingSupport.createGetter(object.getClass(), propertyName);
+        }
+        return Optional.empty();
     }
 
     private boolean isNegativelyCached(CacheKey key) {
@@ -149,6 +170,11 @@ private interface MethodFinder {
         Method apply(Class<?> aClass, String s) throws NoSuchMethodException;
     }
 
+    private Object getPropertyViaRecordMethod(Object object, String propertyName, MethodFinder methodFinder, Object singleArgumentValue) throws NoSuchMethodException {
+        Method method = methodFinder.apply(object.getClass(), propertyName);
+        return invokeMethod(object, singleArgumentValue, method, takesSingleArgumentTypeAsOnlyArgument(method));
+    }
+
     private Object getPropertyViaGetterMethod(Object object, String propertyName, GraphQLType graphQLType, MethodFinder methodFinder, Object singleArgumentValue) throws NoSuchMethodException {
         if (isBooleanProperty(graphQLType)) {
             try {
@@ -204,6 +230,20 @@ private Method findPubliclyAccessibleMethod(CacheKey cacheKey, Class<?> rootClas
         return rootClass.getMethod(methodName);
     }
 
+    /*
+       https://docs.oracle.com/en/java/javase/15/language/records.html
+
+       A record class declares a sequence of fields, and then the appropriate accessors, constructors, equals, hashCode, and toString methods are created automatically.
+
+       Records cannot extend any class - so we need only check the root class for a publicly declared method with the propertyName
+
+       However, we won't just restrict ourselves strictly to true records.  We will find methods that are record like
+       and fetch them - e.g. `object.propertyName()`
+     */
+    private Method findRecordMethod(CacheKey cacheKey, Class<?> rootClass, String methodName) throws NoSuchMethodException {
+        return findPubliclyAccessibleMethod(cacheKey,rootClass,methodName,false);
+    }
+
     private Method findViaSetAccessible(CacheKey cacheKey, Class<?> aClass, String methodName, boolean dfeInUse) throws NoSuchMethodException {
         if (!USE_SET_ACCESSIBLE.get()) {
             throw new FastNoSuchMethodException(methodName);
@@ -306,6 +346,9 @@ public void clearReflectionCache() {
     public boolean setUseSetAccessible(boolean flag) {
         return USE_SET_ACCESSIBLE.getAndSet(flag);
     }
+    public boolean setUseLambdaFactory(boolean flag) {
+        return USE_LAMBDA_FACTORY.getAndSet(flag);
+    }
 
     public boolean setUseNegativeCache(boolean flag) {
         return USE_NEGATIVE_CACHE.getAndSet(flag);

src/main/java/graphql/schema/fetching/LambdaFetchingSupport.java

@@ -15,6 +15,7 @@
 import java.util.List;
 import java.util.Optional;
 import java.util.function.Function;
+import java.util.function.Predicate;
 
 import static java.util.stream.Collectors.toList;
 
@@ -42,15 +43,32 @@ public static Optional<Function<Object, Object>> createGetter(Class<?> sourceCla
                 Function<Object, Object> getterFunction = mkCallFunction(sourceClass, candidateMethod.getName(), candidateMethod.getReturnType());
                 return Optional.of(getterFunction);
             } catch (Throwable ignore) {
+                //
                 // if we cant make a dynamic lambda here, then we give up and let the old property fetching code do its thing
+                // this can happen on runtimes such as GraalVM native where LambdaMetafactory is not supported
+                // and will throw something like :
+                //
+                //    com.oracle.svm.core.jdk.UnsupportedFeatureError: Defining hidden classes at runtime is not supported.
+                //        at org.graalvm.nativeimage.builder/com.oracle.svm.core.util.VMError.unsupportedFeature(VMError.java:89)
             }
         }
         return Optional.empty();
     }
 
 
     private static Method getCandidateMethod(Class<?> sourceClass, String propertyName) {
-        List<Method> allGetterMethods = findGetterMethodsForProperty(sourceClass, propertyName);
+        // property() methods first
+        Predicate<Method> recordLikePredicate = method -> isRecordLike(method) && propertyName.equals(decapitalize(method.getName()));
+        List<Method> recordLikeMethods = findMethodsForProperty(sourceClass,
+                recordLikePredicate);
+        if (!recordLikeMethods.isEmpty()) {
+            return recordLikeMethods.get(0);
+        }
+
+        // getProperty() POJO methods next
+        Predicate<Method> getterPredicate = method -> isGetterNamed(method) && propertyName.equals(mkPropertyNameGetter(method));
+        List<Method> allGetterMethods = findMethodsForProperty(sourceClass,
+                getterPredicate);
         List<Method> pojoGetterMethods = allGetterMethods.stream()
                 .filter(LambdaFetchingSupport::isPossiblePojoMethod)
                 .collect(toList());
@@ -60,10 +78,8 @@ private static Method getCandidateMethod(Class<?> sourceClass, String propertyNa
                 method = findBestBooleanGetter(pojoGetterMethods);
             }
             return checkForSingleParameterPeer(method, allGetterMethods);
-        } else {
-            return null;
         }
-
+        return null;
     }
 
     private static Method checkForSingleParameterPeer(Method candidateMethod, List<Method> allMethods) {
@@ -88,21 +104,18 @@ private static Method findBestBooleanGetter(List<Method> methods) {
     /**
      * Finds all methods in a class hierarchy that match the property name - they might not be suitable but they
      *
-     * @param sourceClass  the class we are looking to work on
-     * @param propertyName the name of the property
+     * @param sourceClass the class we are looking to work on
      *
      * @return a list of getter methods for that property
      */
-    private static List<Method> findGetterMethodsForProperty(Class<?> sourceClass, String propertyName) {
+    private static List<Method> findMethodsForProperty(Class<?> sourceClass, Predicate<Method> predicate) {
         List<Method> methods = new ArrayList<>();
         Class<?> currentClass = sourceClass;
         while (currentClass != null) {
             Method[] declaredMethods = currentClass.getDeclaredMethods();
             for (Method declaredMethod : declaredMethods) {
-                if (isGetterNamed(declaredMethod)) {
-                    if (nameMatches(propertyName, declaredMethod)) {
-                        methods.add(declaredMethod);
-                    }
+                if (predicate.test(declaredMethod)) {
+                    methods.add(declaredMethod);
                 }
             }
             currentClass = currentClass.getSuperclass();
@@ -113,12 +126,6 @@ private static List<Method> findGetterMethodsForProperty(Class<?> sourceClass, S
                 .collect(toList());
     }
 
-
-    private static boolean nameMatches(String propertyName, Method declaredMethod) {
-        String methodPropName = mkPropertyName(declaredMethod);
-        return propertyName.equals(methodPropName);
-    }
-
     private static boolean isPossiblePojoMethod(Method method) {
         return !isObjectMethod(method) &&
                 returnsSomething(method) &&
@@ -127,6 +134,13 @@ private static boolean isPossiblePojoMethod(Method method) {
                 isPublic(method);
     }
 
+    private static boolean isRecordLike(Method method) {
+        return !isObjectMethod(method) &&
+                returnsSomething(method) &&
+                hasNoParameters(method) &&
+                isPublic(method);
+    }
+
     private static boolean isBooleanGetter(Method method) {
         Class<?> returnType = method.getReturnType();
         return isGetterNamed(method) && (returnType.equals(Boolean.class) || returnType.equals(Boolean.TYPE));
@@ -153,7 +167,7 @@ private static boolean isObjectMethod(Method method) {
         return method.getDeclaringClass().equals(Object.class);
     }
 
-    private static String mkPropertyName(Method method) {
+    private static String mkPropertyNameGetter(Method method) {
         //
         // getFooName becomes fooName
         // isFoo becomes foo

src/test/groovy/graphql/schema/PropertyDataFetcherTest.groovy

@@ -2,9 +2,12 @@ package graphql.schema
 
 import graphql.ExecutionInput
 import graphql.TestUtil
+import graphql.schema.fetching.ConfusedPojo
 import graphql.schema.somepackage.ClassWithDFEMethods
 import graphql.schema.somepackage.ClassWithInterfaces
 import graphql.schema.somepackage.ClassWithInteritanceAndInterfaces
+import graphql.schema.somepackage.RecordLikeClass
+import graphql.schema.somepackage.RecordLikeTwoClassesDown
 import graphql.schema.somepackage.TestClass
 import graphql.schema.somepackage.TwoClassesDown
 import spock.lang.Specification
@@ -20,6 +23,7 @@ class PropertyDataFetcherTest extends Specification {
         PropertyDataFetcher.setUseSetAccessible(true)
         PropertyDataFetcher.setUseNegativeCache(true)
         PropertyDataFetcher.clearReflectionCache()
+        PropertyDataFetcherHelper.setUseLambdaFactory(true)
     }
 
     def env(obj) {
@@ -95,6 +99,91 @@ class PropertyDataFetcherTest extends Specification {
         result == null
     }
 
+    def "fetch via record method"() {
+        def environment = env(new RecordLikeClass())
+        when:
+        def fetcher = new PropertyDataFetcher("recordProperty")
+        def result = fetcher.get(environment)
+        then:
+        result == "recordProperty"
+
+        // caching works
+        when:
+        fetcher = new PropertyDataFetcher("recordProperty")
+        result = fetcher.get(environment)
+        then:
+        result == "recordProperty"
+
+        // recordArgumentMethod will not work because it takes a parameter
+        when:
+        fetcher = new PropertyDataFetcher("recordArgumentMethod")
+        result = fetcher.get(environment)
+        then:
+        result == null
+
+        // equals will not work because it takes a parameter
+        when:
+        fetcher = new PropertyDataFetcher("equals")
+        result = fetcher.get(environment)
+        then:
+        result == null
+
+        // we allow hashCode() and toString() because why not - they are valid property names
+        // they might not be that useful but they can be accessed
+
+        when:
+        fetcher = new PropertyDataFetcher("hashCode")
+        result = fetcher.get(environment)
+        then:
+        result == 666
+
+        when:
+        fetcher = new PropertyDataFetcher("toString")
+        result = fetcher.get(environment)
+        then:
+        result == "toString"
+    }
+
+    def "can fetch record like methods that are public and on super classes"() {
+        def environment = env(new RecordLikeTwoClassesDown())
+        when:
+        def fetcher = new PropertyDataFetcher("recordProperty")
+        def result = fetcher.get(environment)
+        then:
+        result == "recordProperty"
+    }
+
+    def "fetch via record method without lambda support"() {
+        PropertyDataFetcherHelper.setUseLambdaFactory(false)
+        PropertyDataFetcherHelper.clearReflectionCache()
+
+        when:
+        def environment = env(new RecordLikeClass())
+        def fetcher = new PropertyDataFetcher("recordProperty")
+        def result = fetcher.get(environment)
+        then:
+        result == "recordProperty"
+
+        when:
+        environment = env(new RecordLikeTwoClassesDown())
+        fetcher = new PropertyDataFetcher("recordProperty")
+        result = fetcher.get(environment)
+        then:
+        result == "recordProperty"
+    }
+
+    def "fetch via record method without lambda support in preference to getter methods"() {
+        PropertyDataFetcherHelper.setUseLambdaFactory(false)
+        PropertyDataFetcherHelper.clearReflectionCache()
+
+        when:
+        def environment = env(new ConfusedPojo())
+        def fetcher = new PropertyDataFetcher("recordLike")
+        def result = fetcher.get(environment)
+        then:
+        result == "recordLike"
+    }
+
     def "fetch via public method"() {
         def environment = env(new TestClass())
         def fetcher = new PropertyDataFetcher("publicProperty")