Adding support for Java 17 & Groovy Records

jr-objects/src/main/java/com/fasterxml/jackson/jr/ob/JSON.java

@@ -261,6 +261,13 @@ public enum Feature
          */
         USE_IS_GETTERS(true, true),
 
+        /**
+         * Feature that provides support for Groovy & JDK14 records, by allowing
+         * reading of "non-get-getters" in a class, (like for a field named <code>amount</code>
+         * the getter would be <code>amount()</code>)
+         * */
+        USE_FIELD_NAME_GETTERS(false,true),
+
         /**
          * Feature that enables use of public fields instead of setters and getters,
          * in cases where no setter/getter is available.

jr-objects/src/main/java/com/fasterxml/jackson/jr/ob/impl/BeanPropertyIntrospector.java

@@ -4,13 +4,17 @@
 import java.lang.reflect.Field;
 import java.lang.reflect.Method;
 import java.lang.reflect.Modifier;
+import java.util.Arrays;
 import java.util.Map;
 import java.util.TreeMap;
 
-import com.fasterxml.jackson.jr.ob.JSON;
 import com.fasterxml.jackson.jr.ob.impl.POJODefinition.Prop;
 import com.fasterxml.jackson.jr.ob.impl.POJODefinition.PropBuilder;
 
+
+import static com.fasterxml.jackson.jr.ob.JSON.Feature.INCLUDE_STATIC_FIELDS;
+import static com.fasterxml.jackson.jr.ob.JSON.Feature.USE_FIELD_NAME_GETTERS;
+
 /**
  * Helper class that jackson-jr uses by default to introspect POJO properties
  * (represented as {@link POJODefinition}) to build general POJO readers
@@ -97,7 +101,9 @@ private static void _introspect(Class<?> currType, Map<String, PropBuilder> prop
         // First, check base type
         _introspect(currType.getSuperclass(), props, features);
 
-        final boolean noStatics = JSON.Feature.INCLUDE_STATIC_FIELDS.isDisabled(features);
+        final boolean noStatics = INCLUDE_STATIC_FIELDS.isDisabled(features);
+        final boolean isFieldNameGettersEnabled = USE_FIELD_NAME_GETTERS.isEnabled(features);
+
         // then public fields (since 2.8); may or may not be ultimately included
         // but at this point still possible
         for (Field f : currType.getDeclaredFields()) {
@@ -146,6 +152,17 @@ private static void _introspect(Class<?> currType, Map<String, PropBuilder> prop
                         _propFrom(props, name).withIsGetter(m);
                     }
                 }
+                else if (isFieldNameGettersEnabled) {
+                    // This will allow getters with field name as their getters, like the ones generated by Groovy
+                    // If method name matches with field name, & method return type matches with field type
+                    // only then it can be considered a direct name getter.
+                    final String decapName = name;
+                    Arrays.stream(currType.getDeclaredFields())
+                            .filter(f -> f.getName().equals(m.getName()))
+                            .filter(f -> Modifier.isPublic(m.getModifiers()) && m.getReturnType().equals(f.getType()))
+                            .findFirst()
+                            .ifPresent(f -> _propFrom(props, decap(decapName)).withGetter(m));
+                }
             } else if (argTypes.length == 1) { // setter?
                 // Non-public setters are fine if we can force access, don't yet check
                 // let's also not bother about return type; setters that return value are fine

jr-test-module/src/test/groovy/GroovyObjectSupportTest.groovy

@@ -2,6 +2,11 @@ import com.fasterxml.jackson.jr.ob.JSON
 import org.junit.Assert
 import org.junit.Test
 
+/**
+ * A minor note on running/debugging this test on local, if you are using intellij, please
+ * change `<packaging>pom</packaging>` to `<packaging>bundle</packaging>`. this is causing
+ * some issue with the IDE.
+ */
 class GroovyObjectSupportTest {
     @Test
     void testSimpleGroovyObject() throws Exception {

jr-test-module/src/test/groovy/GroovyRecordsTest.groovy

@@ -0,0 +1,67 @@
+import com.fasterxml.jackson.jr.ob.JSON
+import org.junit.Assert
+import org.junit.Test
+
+/**
+ * A minor note on running/debugging this test on local, if you are using intellij, please
+ * change `<packaging>pom</packaging>` to `<packaging>bundle</packaging>`. this is causing
+ * some issue with the IDE.
+*/
+class GroovyRecordsTest {
+
+    @Test
+    void testRecord() throws Exception {
+        /* We need to use this since build (8, ubuntu-20.04), will fail Map.of() was added in Java 9*/
+        def map = new HashMap<String, String>()
+        map.put("foo", "bar")
+
+        def json = JSON.builder().enable(JSON.Feature.USE_FIELD_NAME_GETTERS).build().asString(new Cow("foo", map))
+        def expected = """{"message":"foo","object":{"foo":"bar"}}"""
+        Assert.assertEquals(expected, json)
+    }
+
+    @Test
+    void testRecordEquivalentObjects() throws Exception {
+        def expected = """{"message":"foo","object":{"foo":"bar"}}"""
+
+        /* We need to use this since build (8, ubuntu-20.04), will fail Map.of() was added in Java 9*/
+        def map = new HashMap<String, String>()
+        map.put("foo", "bar")
+
+        def json = JSON.builder().enable(JSON.Feature.USE_FIELD_NAME_GETTERS).build().asString(new SimpleGroovyObject("foo", map))
+        Assert.assertEquals(expected, json)
+
+        def json2 = JSON.builder().enable(JSON.Feature.USE_FIELD_NAME_GETTERS).build().asString(new GroovyObjectWithNamedGetters("foo", map))
+        Assert.assertEquals(expected, json2)
+    }
+}
+
+class SimpleGroovyObject {
+    public final String message
+    public final Map<String, String> object
+
+    SimpleGroovyObject(String message, Map<String, String> object) {
+        this.message = message
+        this.object = object
+    }
+}
+
+class GroovyObjectWithNamedGetters {
+    private final String message
+    private final Map<String, String> object
+
+    GroovyObjectWithNamedGetters(String message, Map<String, String> object) {
+        this.message = message
+        this.object = object
+    }
+
+    String message() {
+        return message
+    }
+
+    Map<String, String> object() {
+        return object
+    }
+}
+
+record Cow(String message, Map<String, String> object) {}

jr-test-module/src/test/java/Java14RecordTest.java

@@ -0,0 +1,22 @@
+import com.fasterxml.jackson.jr.ob.JSON;
+import org.junit.Assert;
+import org.junit.Test;
+
+import java.io.IOException;
+import java.util.Map;
+
+/**
+ * This test is in test module since the JDK version to be tested is higher than other, and hence supports Records.
+ */
+public class Java14RecordTest {
+
+    @Test
+    public void testJava14RecordSupport() throws IOException {
+        var expectedString = "{\"message\":\"MOO\",\"object\":{\"Foo\":\"Bar\"}}";
+        var json = JSON.builder().enable(JSON.Feature.USE_FIELD_NAME_GETTERS).build().asString(new Cow("MOO", Map.of("Foo", "Bar")));
+        Assert.assertEquals(expectedString, json);
+    }
+
+    record Cow(String message, Map<String, String> object) {
+    }
+}