Fluent accessor support for pojo config classes (#203)

Author: Squiry

config/config-annotation-processor/src/main/java/ru/tinkoff/kora/config/annotation/processor/ConfigUtils.java

@@ -151,12 +151,14 @@ class FieldAndAccessors {
                     equals = method;
                 } else if (name.equals("hashCode") && method.getParameters().isEmpty()) {
                     hashCode = method;
-                } else {
+                } else if (method.getParameters().isEmpty()) {
                     if (name.startsWith("get")) {
                         fieldsWithAccessors.computeIfAbsent(CommonUtils.decapitalize(name.substring(3)), n -> new FieldAndAccessors()).getter = method;
-                    } else if (name.startsWith("set")) {
-                        fieldsWithAccessors.computeIfAbsent(CommonUtils.decapitalize(name.substring(3)), n -> new FieldAndAccessors()).setter = method;
+                    } else {
+                        fieldsWithAccessors.computeIfAbsent(name, n -> new FieldAndAccessors()).getter = method;
                     }
+                } else if (method.getParameters().size() == 1 && name.startsWith("set")) {
+                    fieldsWithAccessors.computeIfAbsent(CommonUtils.decapitalize(name.substring(3)), n -> new FieldAndAccessors()).setter = method;
                 }
             }
         }
@@ -167,24 +169,27 @@ class FieldAndAccessors {
         var constructors = CommonUtils.findConstructors(te, m -> m.contains(Modifier.PUBLIC));
         var emptyConstructor = constructors.stream().filter(e -> e.getParameters().isEmpty()).findFirst().orElse(null);
         var nonEmptyConstructor = constructors.stream().filter(e -> !e.getParameters().isEmpty()).findFirst().orElse(null);
-        var constructorParams = nonEmptyConstructor == null ? Set.of() : nonEmptyConstructor.getParameters().stream().map(VariableElement::getSimpleName).map(Objects::toString).collect(Collectors.toSet());
+        var constructorParams = nonEmptyConstructor == null ? Map.of() : nonEmptyConstructor.getParameters().stream().collect(Collectors.toMap(
+            p -> p.getSimpleName().toString(),
+            p -> p
+        ));
 
         var seen = new HashSet<String>();
         var fields = new ArrayList<ConfigField>();
         for (var fieldWithAccessors : fieldsWithAccessors.entrySet()) {
             var name = fieldWithAccessors.getKey();
             var value = fieldWithAccessors.getValue();
-            if (value.getter == null) {
+            if (value.getter == null || value.field == null) {
                 continue;
             }
-            if (value.setter == null && !constructorParams.contains(value.field.getSimpleName().toString())) {
+            if (value.setter == null && !constructorParams.containsKey(value.field.getSimpleName().toString())) {
                 continue;
             }
             var fieldType = types.asMemberOf(typeMirror, value.field);
             if (seen.add(name)) {
                 var isNullable = CommonUtils.isNullable(value.field) && !fieldType.getKind().isPrimitive();
                 var mapping = CommonUtils.parseMapping(value.field).getMapping(ConfigClassNames.configValueExtractor);
-                var hasDefault = emptyConstructor != null || !constructorParams.contains(value.field.getSimpleName().toString());
+                var hasDefault = emptyConstructor != null || !constructorParams.containsKey(value.field.getSimpleName().toString());
                 fields.add(new ConfigUtils.ConfigField(
                     name, TypeName.get(fieldType), isNullable, hasDefault, mapping
                 ));

config/config-annotation-processor/src/test/java/ru/tinkoff/kora/config/annotation/processor/AnnotationConfigTest.java

@@ -256,6 +256,11 @@ public boolean equals(Object obj) {
               }
               
               public int hashCode() { return java.util.Objects.hashCode(value); }
+              
+              @Override
+              public String toString() {
+                return "TestConfig[%s]".formatted(value);
+              }
             }
             """);
 
@@ -343,4 +348,46 @@ public String toString() {
             .isEqualTo(expected);
     }
 
+    @Test
+    public void testPojoWithFluent() {
+        var extractor = this.compileConfig(List.of(), """
+            @ru.tinkoff.kora.config.common.annotation.ConfigValueExtractor
+            public class TestConfig {
+              @Nullable
+              private final String value1;
+              @Nullable
+              private final String value2;
+              
+              public TestConfig(String value1, String value2) {
+                this.value1 = value1;
+                this.value2 = value2;
+              }
+              
+              public String value1() {
+                return this.value1;
+              }
+                            
+              public String value2() {
+                return this.value2;
+              }
+              
+              @Override
+              public boolean equals(Object obj) {
+                return obj instanceof TestConfig that && java.util.Objects.equals(this.value1, that.value1) && java.util.Objects.equals(this.value2, that.value2);
+              }
+              
+              public int hashCode() { return java.util.Objects.hash(value1, value2); }
+              
+              public String toString() {
+                return "TestConfig(value1=%s, value2=%s)".formatted(this.value1, this.value2);
+              }
+            }
+            """);
+
+        var expected = newObject("TestConfig", "test", null);
+
+        assertThat(extractor.extract(MapConfigFactory.fromMap(Map.of("value1", "test")).root()))
+            .isEqualTo(expected);
+    }
+
 }

config/config-symbol-processor/src/main/kotlin/ru/tinkoff/kora/config/ksp/ConfigUtils.kt

@@ -44,7 +44,9 @@ object ConfigUtils {
             }
             var equals: KSFunctionDeclaration? = null
             var hashCode: KSFunctionDeclaration? = null
+
             class FieldAndAccessors(var property: KSPropertyDeclaration? = null, var getter: KSFunctionDeclaration? = null, var setter: KSFunctionDeclaration? = null)
+
             val propertyMap = hashMapOf<String, FieldAndAccessors>()
             for (function in typeDecl.getDeclaredFunctions()) {
                 val name = function.simpleName.asString()
@@ -58,16 +60,17 @@ object ConfigUtils {
                 } else {
                     if (name.startsWith("get")) {
                         val propertyName = name.substring(3).replaceFirstChar { it.lowercaseChar() }
-                        propertyMap.computeIfAbsent(propertyName) {FieldAndAccessors()}.getter = function
-                    }
-                    if (name.startsWith("set")) {
+                        propertyMap.computeIfAbsent(propertyName) { FieldAndAccessors() }.getter = function
+                    } else if (name.startsWith("set")) {
                         val propertyName = name.substring(3).replaceFirstChar { it.lowercaseChar() }
-                        propertyMap.computeIfAbsent(propertyName) {FieldAndAccessors()}.setter = function
+                        propertyMap.computeIfAbsent(propertyName) { FieldAndAccessors() }.setter = function
+                    } else {
+                        propertyMap.computeIfAbsent(name) { FieldAndAccessors() }.getter = function
                     }
                 }
             }
             for (property in typeDecl.getAllProperties()) {
-                propertyMap.computeIfAbsent(property.simpleName.asString()) {FieldAndAccessors()}.property = property
+                propertyMap.computeIfAbsent(property.simpleName.asString()) { FieldAndAccessors() }.property = property
             }
             val properties = propertyMap.values.asSequence().filter { it.setter != null && it.getter != null && it.property != null }.map { it.property!! }.toList()
             if (equals == null || hashCode == null) {