diff --git a/utbot-core/src/main/kotlin/org/utbot/common/KClassUtil.kt b/utbot-core/src/main/kotlin/org/utbot/common/KClassUtil.kt
index 1f6bb848a5..7a6158665b 100644
--- a/utbot-core/src/main/kotlin/org/utbot/common/KClassUtil.kt
+++ b/utbot-core/src/main/kotlin/org/utbot/common/KClassUtil.kt
@@ -1,29 +1,11 @@
 package org.utbot.common
 
-import java.lang.reflect.Field
 import java.lang.reflect.InvocationTargetException
 import java.lang.reflect.Method
 
 
 val Class<*>.packageName: String get() = `package`?.name?:""
 
-fun Class<*>.findField(name: String): Field =
-    findFieldOrNull(name) ?: error("Can't find field $name in $this")
-
-fun Class<*>.findFieldOrNull(name: String): Field? = generateSequence(this) { it.superclass }
-    .mapNotNull {
-        try {
-            it.getField(name)
-        } catch (e: NoSuchFieldException) {
-            try {
-                it.getDeclaredField(name)
-            } catch (e: NoSuchFieldException) {
-                null
-            }
-        }
-    }
-    .firstOrNull()
-
 fun Method.invokeCatching(obj: Any?, args: List<Any?>) = try {
     Result.success(invoke(obj, *args.toTypedArray()))
 } catch (e: InvocationTargetException) {
diff --git a/utbot-framework-api/src/main/kotlin/org/utbot/framework/plugin/api/Api.kt b/utbot-framework-api/src/main/kotlin/org/utbot/framework/plugin/api/Api.kt
index 565bb51a25..ae2e311802 100644
--- a/utbot-framework-api/src/main/kotlin/org/utbot/framework/plugin/api/Api.kt
+++ b/utbot-framework-api/src/main/kotlin/org/utbot/framework/plugin/api/Api.kt
@@ -20,7 +20,6 @@ import org.utbot.framework.plugin.api.util.charClassId
 import org.utbot.framework.plugin.api.util.constructor
 import org.utbot.framework.plugin.api.util.doubleClassId
 import org.utbot.framework.plugin.api.util.executableId
-import org.utbot.framework.plugin.api.util.findFieldOrNull
 import org.utbot.framework.plugin.api.util.floatClassId
 import org.utbot.framework.plugin.api.util.id
 import org.utbot.framework.plugin.api.util.intClassId
@@ -30,6 +29,7 @@ import org.utbot.framework.plugin.api.util.jClass
 import org.utbot.framework.plugin.api.util.longClassId
 import org.utbot.framework.plugin.api.util.method
 import org.utbot.framework.plugin.api.util.primitiveTypeJvmNameOrNull
+import org.utbot.framework.plugin.api.util.safeJField
 import org.utbot.framework.plugin.api.util.shortClassId
 import org.utbot.framework.plugin.api.util.toReferenceTypeBytecodeSignature
 import org.utbot.framework.plugin.api.util.voidClassId
@@ -366,7 +366,7 @@ data class UtCompositeModel(
             if (fields.isNotEmpty()) {
                 append(" ")
                 append(fields.entries.joinToString(", ", "{", "}") { (field, value) ->
-                    if (value.classId != classId || value.isNull()) "${field.name}: $value" else "${field.name}: not evaluated"
+                    if (value.classId != classId || value.isNull()) "(${field.declaringClass}) ${field.name}: $value" else "${field.name}: not evaluated"
                 }) // TODO: here we can get an infinite recursion if we have cyclic dependencies.
             }
             if (mocks.isNotEmpty()) {
@@ -876,7 +876,7 @@ open class FieldId(val declaringClass: ClassId, val name: String) {
         return result
     }
 
-    override fun toString() = declaringClass.findFieldOrNull(name).toString()
+    override fun toString() = safeJField.toString()
 }
 
 inline fun <T> withReflection(block: () -> T): T {
diff --git a/utbot-framework-api/src/main/kotlin/org/utbot/framework/plugin/api/impl/FieldIdStrategies.kt b/utbot-framework-api/src/main/kotlin/org/utbot/framework/plugin/api/impl/FieldIdStrategies.kt
index 8ce32fdbc2..21e23f0b26 100644
--- a/utbot-framework-api/src/main/kotlin/org/utbot/framework/plugin/api/impl/FieldIdStrategies.kt
+++ b/utbot-framework-api/src/main/kotlin/org/utbot/framework/plugin/api/impl/FieldIdStrategies.kt
@@ -3,7 +3,7 @@ package org.utbot.framework.plugin.api.impl
 import org.utbot.framework.plugin.api.ClassId
 import org.utbot.framework.plugin.api.FieldId
 import org.utbot.framework.plugin.api.classId
-import org.utbot.framework.plugin.api.util.field
+import org.utbot.framework.plugin.api.util.jField
 import org.utbot.framework.plugin.api.util.id
 import java.lang.reflect.Modifier
 import soot.Scene
@@ -32,25 +32,25 @@ interface FieldIdStrategy {
 class FieldIdReflectionStrategy(val fieldId: FieldId) : FieldIdStrategy {
 
     override val isPublic: Boolean
-        get() = Modifier.isPublic(fieldId.field.modifiers)
+        get() = Modifier.isPublic(fieldId.jField.modifiers)
 
     override val isProtected: Boolean
-        get() = Modifier.isProtected(fieldId.field.modifiers)
+        get() = Modifier.isProtected(fieldId.jField.modifiers)
 
     override val isPrivate: Boolean
-        get() = Modifier.isPrivate(fieldId.field.modifiers)
+        get() = Modifier.isPrivate(fieldId.jField.modifiers)
 
     override val isFinal: Boolean
-        get() = Modifier.isFinal(fieldId.field.modifiers)
+        get() = Modifier.isFinal(fieldId.jField.modifiers)
 
     override val isStatic: Boolean
-        get() = Modifier.isStatic(fieldId.field.modifiers)
+        get() = Modifier.isStatic(fieldId.jField.modifiers)
 
     override val isSynthetic: Boolean
-        get() = fieldId.field.isSynthetic
+        get() = fieldId.jField.isSynthetic
 
     override val type: ClassId
-        get() = fieldId.field.type.id
+        get() = fieldId.jField.type.id
 }
 
 class FieldIdSootStrategy(val declaringClass: ClassId, val fieldId: FieldId) : FieldIdStrategy {
diff --git a/utbot-framework-api/src/main/kotlin/org/utbot/framework/plugin/api/util/IdUtil.kt b/utbot-framework-api/src/main/kotlin/org/utbot/framework/plugin/api/util/IdUtil.kt
index 02779a6e93..29e4cc8995 100644
--- a/utbot-framework-api/src/main/kotlin/org/utbot/framework/plugin/api/util/IdUtil.kt
+++ b/utbot-framework-api/src/main/kotlin/org/utbot/framework/plugin/api/util/IdUtil.kt
@@ -1,6 +1,5 @@
 package org.utbot.framework.plugin.api.util
 
-import org.utbot.common.findFieldOrNull
 import org.utbot.framework.plugin.api.BuiltinClassId
 import org.utbot.framework.plugin.api.BuiltinMethodId
 import org.utbot.framework.plugin.api.ClassId
@@ -286,9 +285,17 @@ val ClassId.isMap: Boolean
 val ClassId.isIterableOrMap: Boolean
     get() = isIterable || isMap
 
-fun ClassId.findFieldOrNull(fieldName: String): Field? = jClass.findFieldOrNull(fieldName)
+fun ClassId.findFieldByIdOrNull(fieldId: FieldId): Field? {
+    if (isNotSubtypeOf(fieldId.declaringClass)) {
+        return null
+    }
+
+    return fieldId.safeJField
+}
 
-fun ClassId.hasField(fieldName: String): Boolean = findFieldOrNull(fieldName) != null
+fun ClassId.hasField(fieldId: FieldId): Boolean {
+    return findFieldByIdOrNull(fieldId) != null
+}
 
 fun ClassId.defaultValueModel(): UtModel = when (this) {
     intClassId -> UtPrimitiveModel(0)
@@ -303,11 +310,12 @@ fun ClassId.defaultValueModel(): UtModel = when (this) {
 }
 
 // FieldId utils
+val FieldId.safeJField: Field?
+    get() = declaringClass.jClass.declaredFields.firstOrNull { it.name == name }
 
 // TODO: maybe cache it somehow in the future
-val FieldId.field: Field
-    get() = declaringClass.jClass.declaredFields.firstOrNull { it.name == name }
-        ?: error("Field $name is not found in class ${declaringClass.jClass.name}")
+val FieldId.jField: Field
+    get() = safeJField ?: error("Field $name is not declared in class ${declaringClass.jClass.name}")
 
 // https://docstore.mik.ua/orelly/java-ent/jnut/ch03_13.htm
 val FieldId.isInnerClassEnclosingClassReference: Boolean
diff --git a/utbot-framework/src/main/kotlin/org/utbot/engine/Hierarchy.kt b/utbot-framework/src/main/kotlin/org/utbot/engine/Hierarchy.kt
index 113485b18a..c610ab822c 100644
--- a/utbot-framework/src/main/kotlin/org/utbot/engine/Hierarchy.kt
+++ b/utbot-framework/src/main/kotlin/org/utbot/engine/Hierarchy.kt
@@ -28,10 +28,12 @@ class Hierarchy(private val typeRegistry: TypeRegistry) {
         type as? RefType ?: error("$type is not a refType")
 
         val realType = typeRegistry.findRealType(type) as RefType
+        val realFieldDeclaringType = typeRegistry.findRealType(field.declaringClass.type) as RefType
 
-        val ancestorType = ancestors(realType.sootClass.id).lastOrNull { it.declaresField(field.subSignature) }?.type
-            ?: error("No such field ${field.subSignature} found in ${realType.sootClass.name}")
-        return ChunkId("$ancestorType", field.name)
+        if (realFieldDeclaringType.sootClass !in ancestors(realType.sootClass.id)) {
+            error("No such field ${field.subSignature} found in ${realType.sootClass.name}")
+        }
+        return ChunkId("$realFieldDeclaringType", field.name)
     }
 
     /**
diff --git a/utbot-framework/src/main/kotlin/org/utbot/engine/Strings.kt b/utbot-framework/src/main/kotlin/org/utbot/engine/Strings.kt
index cb0e1fba1d..8c31fda3ad 100644
--- a/utbot-framework/src/main/kotlin/org/utbot/engine/Strings.kt
+++ b/utbot-framework/src/main/kotlin/org/utbot/engine/Strings.kt
@@ -313,7 +313,7 @@ sealed class UtAbstractStringBuilderWrapper(className: String) : BaseOverriddenW
 
         val arrayValuesChunkId = typeRegistry.arrayChunkId(charArrayType)
 
-        val valuesFieldChunkId = hierarchy.chunkIdForField(utStringClass.type, overriddenClass.valueField)
+        val valuesFieldChunkId = hierarchy.chunkIdForField(overriddenClass.type, overriddenClass.valueField)
         val valuesArrayAddrDescriptor = MemoryChunkDescriptor(valuesFieldChunkId, wrapper.type, charType)
         val valuesArrayAddr = findArray(valuesArrayAddrDescriptor, MemoryState.CURRENT).select(wrapper.addr)
 
diff --git a/utbot-framework/src/main/kotlin/org/utbot/engine/Traverser.kt b/utbot-framework/src/main/kotlin/org/utbot/engine/Traverser.kt
index 4563012cb4..74c8d7b624 100644
--- a/utbot-framework/src/main/kotlin/org/utbot/engine/Traverser.kt
+++ b/utbot-framework/src/main/kotlin/org/utbot/engine/Traverser.kt
@@ -8,7 +8,6 @@ import kotlinx.collections.immutable.toPersistentMap
 import kotlinx.collections.immutable.toPersistentSet
 import org.utbot.common.WorkaroundReason.HACK
 import org.utbot.common.WorkaroundReason.REMOVE_ANONYMOUS_CLASSES
-import org.utbot.common.findField
 import org.utbot.common.unreachableBranch
 import org.utbot.common.withAccessibility
 import org.utbot.common.workaround
@@ -90,8 +89,9 @@ import org.utbot.framework.plugin.api.MethodId
 import org.utbot.framework.plugin.api.UtMethod
 import org.utbot.framework.plugin.api.classId
 import org.utbot.framework.plugin.api.id
-import org.utbot.framework.plugin.api.util.id
+import org.utbot.framework.plugin.api.util.jField
 import org.utbot.framework.plugin.api.util.jClass
+import org.utbot.framework.plugin.api.util.id
 import org.utbot.framework.plugin.api.util.signature
 import org.utbot.framework.plugin.api.util.utContext
 import org.utbot.framework.util.executableId
@@ -582,7 +582,7 @@ class Traverser(
         declaringClass: SootClass,
         stmt: Stmt
     ): SymbolicStateUpdate {
-        val concreteValue = extractConcreteValue(field, declaringClass)
+        val concreteValue = extractConcreteValue(field)
         val (symbolicResult, symbolicStateUpdate) = toMethodResult(concreteValue, field.type)
         val symbolicValue = (symbolicResult as SymbolicSuccess).value
 
@@ -634,12 +634,20 @@ class Traverser(
     // Some fields are inaccessible with reflection, so we have to instantiate it by ourselves.
     // Otherwise, extract it from the class.
     // TODO JIRA:1593
-    private fun extractConcreteValue(field: SootField, declaringClass: SootClass): Any? =
+    private fun extractConcreteValue(field: SootField): Any? =
         when (field.signature) {
             SECURITY_FIELD_SIGNATURE -> SecurityManager()
             FIELD_FILTER_MAP_FIELD_SIGNATURE -> mapOf(Reflection::class to arrayOf("fieldFilterMap", "methodFilterMap"))
             METHOD_FILTER_MAP_FIELD_SIGNATURE -> emptyMap<Class<*>, Array<String>>()
-            else -> declaringClass.id.jClass.findField(field.name).let { it.withAccessibility { it.get(null) } }
+            else -> {
+                val fieldId = field.fieldId
+                val jField = fieldId.jField
+                jField.let {
+                    it.withAccessibility {
+                        it.get(null)
+                    }
+                }
+            }
         }
 
     private fun isStaticInstanceInMethodResult(id: ClassId, methodResult: MethodResult?) =
diff --git a/utbot-framework/src/main/kotlin/org/utbot/engine/TypeResolver.kt b/utbot-framework/src/main/kotlin/org/utbot/engine/TypeResolver.kt
index 95565eb600..323dd552e6 100644
--- a/utbot-framework/src/main/kotlin/org/utbot/engine/TypeResolver.kt
+++ b/utbot-framework/src/main/kotlin/org/utbot/engine/TypeResolver.kt
@@ -70,8 +70,6 @@ class TypeResolver(private val typeRegistry: TypeRegistry, private val hierarchy
         hierarchy
             .ancestors(type.sootClass.id)
             .flatMap { it.fields }
-            .asReversed() // to take fields of the farthest parent in the distinctBy
-            .distinctBy { it.name } // TODO we lose hidden fields here JIRA:315
     }
 
     /**
diff --git a/utbot-framework/src/main/kotlin/org/utbot/engine/ValueConstructor.kt b/utbot-framework/src/main/kotlin/org/utbot/engine/ValueConstructor.kt
index 06928beda1..74750c6005 100644
--- a/utbot-framework/src/main/kotlin/org/utbot/engine/ValueConstructor.kt
+++ b/utbot-framework/src/main/kotlin/org/utbot/engine/ValueConstructor.kt
@@ -1,7 +1,5 @@
 package org.utbot.engine
 
-import org.utbot.common.findField
-import org.utbot.common.findFieldOrNull
 import org.utbot.common.invokeCatching
 import org.utbot.common.withAccessibility
 import org.utbot.framework.plugin.api.ClassId
@@ -37,6 +35,7 @@ import org.utbot.framework.plugin.api.UtValueExecutionState
 import org.utbot.framework.plugin.api.UtVoidModel
 import org.utbot.framework.plugin.api.isMockModel
 import org.utbot.framework.plugin.api.util.constructor
+import org.utbot.framework.plugin.api.util.jField
 import org.utbot.framework.plugin.api.util.jClass
 import org.utbot.framework.plugin.api.util.method
 import org.utbot.framework.plugin.api.util.utContext
@@ -212,9 +211,8 @@ class ValueConstructor {
         val classInstance = javaClass.anyInstance
         constructedObjects[model] = classInstance
 
-        model.fields.forEach { (field, fieldModel) ->
-            val declaredField =
-                javaClass.findFieldOrNull(field.name) ?: error("Can't find field: $field for $javaClass")
+        model.fields.forEach { (fieldId, fieldModel) ->
+            val declaredField = fieldId.jField
             val accessible = declaredField.isAccessible
 
             try {
@@ -228,7 +226,7 @@ class ValueConstructor {
                         fieldModel.classId.name,
                         model.classId.name,
                         UtConcreteValue(classInstance),
-                        field.name
+                        fieldId.name
                     )
                 }
                 val value = construct(fieldModel, target).value
@@ -360,7 +358,7 @@ class ValueConstructor {
         val instanceClassId = instanceModel.classId
         val fieldModel = directSetterModel.fieldModel
 
-        val field = instance::class.java.findField(directSetterModel.fieldId.name)
+        val field = directSetterModel.fieldId.jField
         val isAccessible = field.isAccessible
 
         try {
diff --git a/utbot-framework/src/main/kotlin/org/utbot/engine/util/statics/concrete/EnumConcreteUtils.kt b/utbot-framework/src/main/kotlin/org/utbot/engine/util/statics/concrete/EnumConcreteUtils.kt
index f1d547628c..96329b4c01 100644
--- a/utbot-framework/src/main/kotlin/org/utbot/engine/util/statics/concrete/EnumConcreteUtils.kt
+++ b/utbot-framework/src/main/kotlin/org/utbot/engine/util/statics/concrete/EnumConcreteUtils.kt
@@ -10,7 +10,7 @@ import org.utbot.engine.pc.select
 import org.utbot.engine.symbolic.SymbolicStateUpdate
 import org.utbot.engine.symbolic.asHardConstraint
 import org.utbot.framework.plugin.api.FieldId
-import org.utbot.framework.plugin.api.util.field
+import org.utbot.framework.plugin.api.util.jField
 import soot.SootClass
 import soot.SootField
 import soot.SootMethod
@@ -43,7 +43,7 @@ fun associateEnumSootFieldsWithConcreteValues(
     enumConstants: List<Enum<*>>
 ): List<Pair<SootField, List<Any>>> =
     enumFields.map { enumSootField ->
-        val enumField = enumSootField.fieldId.field
+        val enumField = enumSootField.fieldId.jField
 
         val fieldValues = if (enumSootField.isStatic) {
             val staticFieldValue = enumField.withAccessibility { enumField.get(null) }
diff --git a/utbot-framework/src/main/kotlin/org/utbot/framework/codegen/model/constructor/tree/CgFieldStateManager.kt b/utbot-framework/src/main/kotlin/org/utbot/framework/codegen/model/constructor/tree/CgFieldStateManager.kt
index 570dbe3a6f..64a50e17a8 100644
--- a/utbot-framework/src/main/kotlin/org/utbot/framework/codegen/model/constructor/tree/CgFieldStateManager.kt
+++ b/utbot-framework/src/main/kotlin/org/utbot/framework/codegen/model/constructor/tree/CgFieldStateManager.kt
@@ -177,7 +177,7 @@ internal class CgFieldStateManagerImpl(val context: CgContext)
                     }
 
                     // if previous field has type that does not have current field, this field is inaccessible
-                    if (index > 0 && !path[index - 1].type.hasField(fieldPathElement.field.name)) {
+                    if (index > 0 && !path[index - 1].type.hasField(fieldPathElement.field)) {
                         lastAccessibleIndex = index - 1
                         break
                     }
diff --git a/utbot-framework/src/main/kotlin/org/utbot/framework/codegen/model/constructor/tree/CgMethodConstructor.kt b/utbot-framework/src/main/kotlin/org/utbot/framework/codegen/model/constructor/tree/CgMethodConstructor.kt
index 3a5bc8e7c3..744eecb7fa 100644
--- a/utbot-framework/src/main/kotlin/org/utbot/framework/codegen/model/constructor/tree/CgMethodConstructor.kt
+++ b/utbot-framework/src/main/kotlin/org/utbot/framework/codegen/model/constructor/tree/CgMethodConstructor.kt
@@ -121,7 +121,7 @@ import org.utbot.framework.plugin.api.util.doubleArrayClassId
 import org.utbot.framework.plugin.api.util.doubleClassId
 import org.utbot.framework.plugin.api.util.doubleWrapperClassId
 import org.utbot.framework.plugin.api.util.executable
-import org.utbot.framework.plugin.api.util.field
+import org.utbot.framework.plugin.api.util.jField
 import org.utbot.framework.plugin.api.util.floatArrayClassId
 import org.utbot.framework.plugin.api.util.floatClassId
 import org.utbot.framework.plugin.api.util.floatWrapperClassId
@@ -873,8 +873,8 @@ internal class CgMethodConstructor(val context: CgContext) : CgContextOwner by c
     private fun FieldId.getAccessExpression(variable: CgVariable): CgExpression =
         // Can directly access field only if it is declared in variable class (or in its ancestors)
         // and is accessible from current package
-        if (variable.type.hasField(name) && isAccessibleFrom(testClassPackageName)) {
-            if (field.isStatic) CgStaticFieldAccess(this) else CgFieldAccess(variable, this)
+        if (variable.type.hasField(this) && isAccessibleFrom(testClassPackageName)) {
+            if (jField.isStatic) CgStaticFieldAccess(this) else CgFieldAccess(variable, this)
         } else {
             testClassThisInstance[getFieldValue](variable, stringLiteral(name))
         }
diff --git a/utbot-framework/src/main/kotlin/org/utbot/framework/codegen/model/constructor/tree/CgVariableConstructor.kt b/utbot-framework/src/main/kotlin/org/utbot/framework/codegen/model/constructor/tree/CgVariableConstructor.kt
index 880b199022..0f13a1a958 100644
--- a/utbot-framework/src/main/kotlin/org/utbot/framework/codegen/model/constructor/tree/CgVariableConstructor.kt
+++ b/utbot-framework/src/main/kotlin/org/utbot/framework/codegen/model/constructor/tree/CgVariableConstructor.kt
@@ -47,8 +47,8 @@ import org.utbot.framework.plugin.api.UtPrimitiveModel
 import org.utbot.framework.plugin.api.UtReferenceModel
 import org.utbot.framework.plugin.api.UtVoidModel
 import org.utbot.framework.plugin.api.util.defaultValueModel
-import org.utbot.framework.plugin.api.util.field
-import org.utbot.framework.plugin.api.util.findFieldOrNull
+import org.utbot.framework.plugin.api.util.jField
+import org.utbot.framework.plugin.api.util.findFieldByIdOrNull
 import org.utbot.framework.plugin.api.util.id
 import org.utbot.framework.plugin.api.util.intClassId
 import org.utbot.framework.plugin.api.util.isArray
@@ -128,9 +128,9 @@ internal class CgVariableConstructor(val context: CgContext) :
         }
 
         for ((fieldId, fieldModel) in model.fields) {
-            val field = fieldId.field
+            val field = fieldId.jField
             val variableForField = getOrCreateVariable(fieldModel)
-            val fieldFromVariableSpecifiedType = obj.type.findFieldOrNull(field.name)
+            val fieldFromVariableSpecifiedType = obj.type.findFieldByIdOrNull(fieldId)
 
             // we cannot set field directly if variable declared type does not have such field
             // or we cannot directly create variable for field with the specified type (it is private, for example)
diff --git a/utbot-framework/src/main/kotlin/org/utbot/framework/concrete/MockValueConstructor.kt b/utbot-framework/src/main/kotlin/org/utbot/framework/concrete/MockValueConstructor.kt
index d1452b2cef..170f9c743b 100644
--- a/utbot-framework/src/main/kotlin/org/utbot/framework/concrete/MockValueConstructor.kt
+++ b/utbot-framework/src/main/kotlin/org/utbot/framework/concrete/MockValueConstructor.kt
@@ -1,7 +1,5 @@
 package org.utbot.framework.concrete
 
-import org.utbot.common.findField
-import org.utbot.common.findFieldOrNull
 import org.utbot.common.invokeCatching
 import org.utbot.framework.plugin.api.ClassId
 import org.utbot.framework.plugin.api.ConstructorId
@@ -33,6 +31,7 @@ import org.utbot.framework.plugin.api.UtVoidModel
 import org.utbot.framework.plugin.api.isMockModel
 import org.utbot.framework.plugin.api.util.constructor
 import org.utbot.framework.plugin.api.util.executableId
+import org.utbot.framework.plugin.api.util.jField
 import org.utbot.framework.plugin.api.util.jClass
 import org.utbot.framework.plugin.api.util.method
 import org.utbot.framework.plugin.api.util.utContext
@@ -169,9 +168,8 @@ class MockValueConstructor(
             mockInstance
         }
 
-        model.fields.forEach { (field, fieldModel) ->
-            val declaredField =
-                javaClass.findFieldOrNull(field.name) ?: error("Can't find field: $field for $javaClass")
+        model.fields.forEach { (fieldId, fieldModel) ->
+            val declaredField = fieldId.jField
             val accessible = declaredField.isAccessible
             declaredField.isAccessible = true
 
@@ -179,7 +177,7 @@ class MockValueConstructor(
             modifiersField.isAccessible = true
 
             val target = mockTarget(fieldModel) {
-                FieldMockTarget(fieldModel.classId.name, model.classId.name, UtConcreteValue(classInstance), field.name)
+                FieldMockTarget(fieldModel.classId.name, model.classId.name, UtConcreteValue(classInstance), fieldId.name)
             }
             val value = construct(fieldModel, target).value
             val instance = if (Modifier.isStatic(declaredField.modifiers)) null else classInstance
@@ -394,7 +392,7 @@ class MockValueConstructor(
         val instanceClassId = instanceModel.classId
         val fieldModel = directSetterModel.fieldModel
 
-        val field = instance::class.java.findField(directSetterModel.fieldId.name)
+        val field = directSetterModel.fieldId.jField
         val isAccessible = field.isAccessible
 
         try {
diff --git a/utbot-framework/src/main/kotlin/org/utbot/framework/concrete/UtExecutionInstrumentation.kt b/utbot-framework/src/main/kotlin/org/utbot/framework/concrete/UtExecutionInstrumentation.kt
index 5c587a48ee..6a7ca07ec2 100644
--- a/utbot-framework/src/main/kotlin/org/utbot/framework/concrete/UtExecutionInstrumentation.kt
+++ b/utbot-framework/src/main/kotlin/org/utbot/framework/concrete/UtExecutionInstrumentation.kt
@@ -23,7 +23,7 @@ import org.utbot.framework.plugin.api.UtNewInstanceInstrumentation
 import org.utbot.framework.plugin.api.UtStaticMethodInstrumentation
 import org.utbot.framework.plugin.api.UtTimeoutException
 import org.utbot.framework.plugin.api.util.UtContext
-import org.utbot.framework.plugin.api.util.field
+import org.utbot.framework.plugin.api.util.jField
 import org.utbot.framework.plugin.api.util.id
 import org.utbot.framework.plugin.api.util.singleExecutableId
 import org.utbot.framework.plugin.api.util.utContext
@@ -178,7 +178,7 @@ object UtExecutionInstrumentation : Instrumentation<UtConcreteExecutionResult> {
                     val stateAfterParametersWithThis = params.map { construct(it.value, it.clazz.id) }
                     val stateAfterStatics = (staticFields.keys/* + traceHandler.computePutStatics()*/)
                         .associateWith { fieldId ->
-                            fieldId.field.run { construct(withAccessibility { get(null) }, fieldId.type) }
+                            fieldId.jField.run { construct(withAccessibility { get(null) }, fieldId.type) }
                         }
                     val (stateAfterThis, stateAfterParameters) = if (stateBefore.thisInstance == null) {
                         null to stateAfterParametersWithThis
@@ -258,7 +258,7 @@ object UtExecutionInstrumentation : Instrumentation<UtConcreteExecutionResult> {
         val savedFields = mutableMapOf<FieldId, Any?>()
         try {
             staticFields.forEach { (fieldId, value) ->
-                fieldId.field.run {
+                fieldId.jField.run {
                     withAccessibility {
                         savedFields[fieldId] = get(null)
                         set(null, value)
@@ -268,7 +268,7 @@ object UtExecutionInstrumentation : Instrumentation<UtConcreteExecutionResult> {
             return block()
         } finally {
             savedFields.forEach { (fieldId, value) ->
-                fieldId.field.run {
+                fieldId.jField.run {
                     withAccessibility {
                         set(null, value)
                     }
diff --git a/utbot-framework/src/test/kotlin/org/utbot/examples/UtModelTestCaseChecker.kt b/utbot-framework/src/test/kotlin/org/utbot/examples/UtModelTestCaseChecker.kt
index 177f63565b..2d66c07750 100644
--- a/utbot-framework/src/test/kotlin/org/utbot/examples/UtModelTestCaseChecker.kt
+++ b/utbot-framework/src/test/kotlin/org/utbot/examples/UtModelTestCaseChecker.kt
@@ -6,10 +6,10 @@ import org.utbot.common.ClassLocation
 import org.utbot.common.FileUtil.findPathToClassFiles
 import org.utbot.common.FileUtil.locateClass
 import org.utbot.common.WorkaroundReason.HACK
-import org.utbot.common.findField
 import org.utbot.common.workaround
 import org.utbot.engine.prettify
 import org.utbot.framework.UtSettings.checkSolverTimeoutMillis
+import org.utbot.framework.plugin.api.ClassId
 import org.utbot.framework.plugin.api.CodegenLanguage
 import org.utbot.framework.plugin.api.FieldId
 import org.utbot.framework.plugin.api.MockStrategyApi
@@ -27,8 +27,6 @@ import org.utbot.framework.plugin.api.getOrThrow
 import org.utbot.framework.plugin.api.util.UtContext
 import org.utbot.framework.plugin.api.util.defaultValueModel
 import org.utbot.framework.plugin.api.util.executableId
-import org.utbot.framework.plugin.api.util.fieldId
-import org.utbot.framework.plugin.api.util.jClass
 import org.utbot.framework.plugin.api.util.withUtContext
 import java.nio.file.Path
 import kotlin.reflect.KClass
@@ -176,8 +174,8 @@ internal abstract class UtModelTestCaseChecker(
     /**
      * Finds field model in [UtCompositeModel] and [UtAssembleModel]. For assemble model supports direct field access only.
      */
-    protected fun UtModel.findField(fieldName: String): UtModel =
-        findField(this.classId.jClass.findField(fieldName).fieldId)
+    protected fun UtModel.findField(fieldName: String, declaringClass: ClassId = this.classId): UtModel =
+        findField(FieldId(declaringClass, fieldName))
 
     /**
      * Finds field model in [UtCompositeModel] and [UtAssembleModel]. For assemble model supports direct field access only.
diff --git a/utbot-framework/src/test/kotlin/org/utbot/examples/enums/ClassWithEnumTest.kt b/utbot-framework/src/test/kotlin/org/utbot/examples/enums/ClassWithEnumTest.kt
index 48fb11b8ba..57628fc21c 100644
--- a/utbot-framework/src/test/kotlin/org/utbot/examples/enums/ClassWithEnumTest.kt
+++ b/utbot-framework/src/test/kotlin/org/utbot/examples/enums/ClassWithEnumTest.kt
@@ -1,6 +1,5 @@
 package org.utbot.examples.enums
 
-import org.utbot.common.findField
 import org.utbot.examples.UtValueTestCaseChecker
 import org.utbot.examples.DoNotCalculate
 import org.utbot.examples.enums.ClassWithEnum.StatusEnum.ERROR
@@ -13,6 +12,7 @@ import org.utbot.framework.plugin.api.FieldId
 import org.utbot.framework.plugin.api.util.id
 import org.junit.jupiter.api.Disabled
 import org.junit.jupiter.api.Test
+import org.utbot.framework.plugin.api.util.jField
 
 class ClassWithEnumTest : UtValueTestCaseChecker(testClass = ClassWithEnum::class) {
     @Test
@@ -111,7 +111,7 @@ class ClassWithEnumTest : UtValueTestCaseChecker(testClass = ClassWithEnum::clas
             eq(1),
             { t, staticsAfter, r ->
                 // for some reasons x is inaccessible
-                val x = t.javaClass.findField("x").get(t) as Int
+                val x = FieldId(t.javaClass.id, "x").jField.get(t) as Int
 
                 val y = staticsAfter[FieldId(ClassWithEnum.ClassWithStaticField::class.id, "y")]!!.value as Int
 
diff --git a/utbot-framework/src/test/kotlin/org/utbot/examples/objects/HiddenFieldAccessModifiersTest.kt b/utbot-framework/src/test/kotlin/org/utbot/examples/objects/HiddenFieldAccessModifiersTest.kt
new file mode 100644
index 0000000000..2a66eb2288
--- /dev/null
+++ b/utbot-framework/src/test/kotlin/org/utbot/examples/objects/HiddenFieldAccessModifiersTest.kt
@@ -0,0 +1,21 @@
+package org.utbot.examples.objects
+
+import org.utbot.examples.UtValueTestCaseChecker
+import org.utbot.examples.eq
+import org.junit.jupiter.api.Test
+
+internal class HiddenFieldAccessModifiersTest : UtValueTestCaseChecker(testClass = HiddenFieldAccessModifiersExample::class) {
+    @Test
+    fun testCheckSuperFieldEqualsOne() {
+        // TODO: currently, codegen can't handle tests with field hiding (see #646)
+        withEnabledTestingCodeGeneration(testCodeGeneration = false) {
+            check(
+                HiddenFieldAccessModifiersExample::checkSuperFieldEqualsOne,
+                eq(3),
+                { o, _ -> o == null },
+                { _, r -> r == true },
+                { _, r -> r == false },
+            )
+        }
+    }
+}
\ No newline at end of file
diff --git a/utbot-framework/src/test/kotlin/org/utbot/examples/objects/HiddenFieldExampleTest.kt b/utbot-framework/src/test/kotlin/org/utbot/examples/objects/HiddenFieldExampleTest.kt
index 70664a6359..d316d2a68d 100644
--- a/utbot-framework/src/test/kotlin/org/utbot/examples/objects/HiddenFieldExampleTest.kt
+++ b/utbot-framework/src/test/kotlin/org/utbot/examples/objects/HiddenFieldExampleTest.kt
@@ -3,12 +3,10 @@ package org.utbot.examples.objects
 import org.utbot.examples.UtValueTestCaseChecker
 import org.utbot.examples.DoNotCalculate
 import org.utbot.examples.eq
-import org.junit.jupiter.api.Disabled
 import org.junit.jupiter.api.Test
 
 internal class HiddenFieldExampleTest : UtValueTestCaseChecker(testClass = HiddenFieldExample::class) {
     @Test
-    // Engine creates HiddenFieldSuccClass instead of HiddenFieldSuperClass, feels wrong field and matchers fail
     fun testCheckHiddenField() {
         check(
             HiddenFieldExample::checkHiddenField,
@@ -22,18 +20,18 @@ internal class HiddenFieldExampleTest : UtValueTestCaseChecker(testClass = Hidde
     }
 
     @Test
-    @Disabled("SAT-315 Engine cannot work with hidden fields")
-    // Engine translates calls to super.b as calls to succ.b
     fun testCheckSuccField() {
-        check(
-            HiddenFieldExample::checkSuccField,
-            eq(5),
-            { o, _ -> o == null },
-            { o, r -> o.a == 1 && r == 1 },
-            { o, r -> o.a != 1 && o.b == 2.0 && r == 2 },
-            { o, r -> o.a != 1 && o.b != 2.0 && (o as HiddenFieldSuperClass).b == 3 && r == 3 },
-            { o, r -> o.a != 1 && o.b != 2.0 && (o as HiddenFieldSuperClass).b != 3 && r == 4 },
-            coverage = DoNotCalculate
-        )
+        // TODO: currently, codegen can't handle tests with field hiding (see #646)
+        withEnabledTestingCodeGeneration(testCodeGeneration = false) {
+            check(
+                HiddenFieldExample::checkSuccField,
+                eq(5),
+                { o, _ -> o == null },
+                { o, r -> o.a == 1 && r == 1 },
+                { o, r -> o.a != 1 && o.b == 2.0 && r == 2 },
+                { o, r -> o.a != 1 && o.b != 2.0 && (o as HiddenFieldSuperClass).b == 3 && r == 3 },
+                { o, r -> o.a != 1 && o.b != 2.0 && (o as HiddenFieldSuperClass).b != 3 && r == 4 },
+            )
+        }
     }
 }
\ No newline at end of file
diff --git a/utbot-instrumentation-tests/src/test/kotlin/org/utbot/examples/et/TestStaticsUsage.kt b/utbot-instrumentation-tests/src/test/kotlin/org/utbot/examples/et/TestStaticsUsage.kt
index a7ec3e5780..f4aef6ead6 100644
--- a/utbot-instrumentation-tests/src/test/kotlin/org/utbot/examples/et/TestStaticsUsage.kt
+++ b/utbot-instrumentation-tests/src/test/kotlin/org/utbot/examples/et/TestStaticsUsage.kt
@@ -3,7 +3,7 @@ package org.utbot.examples.et
 import org.utbot.examples.objects.ObjectWithStaticFieldsClass
 import org.utbot.examples.objects.ObjectWithStaticFieldsExample
 import org.utbot.framework.plugin.api.util.UtContext
-import org.utbot.framework.plugin.api.util.field
+import org.utbot.framework.plugin.api.util.jField
 import org.utbot.instrumentation.execute
 import org.utbot.instrumentation.instrumentation.et.ExecutionTraceInstrumentation
 import org.utbot.instrumentation.withInstrumentation
@@ -39,7 +39,7 @@ class StaticsUsageDetectionTest {
             classInstance.x = 200
             classInstance.y = 200
             val result = it.execute(ObjectWithStaticFieldsExample::setStaticField, arrayOf(instance, classInstance))
-            assertEquals(ObjectWithStaticFieldsClass::staticValue.javaField, result.usedStatics.single().field)
+            assertEquals(ObjectWithStaticFieldsClass::staticValue.javaField, result.usedStatics.single().jField)
         }
     }
 
diff --git a/utbot-instrumentation/src/main/kotlin/org/utbot/instrumentation/instrumentation/InvokeWithStaticsInstrumentation.kt b/utbot-instrumentation/src/main/kotlin/org/utbot/instrumentation/instrumentation/InvokeWithStaticsInstrumentation.kt
index 0d7c785153..b4ea56bab0 100644
--- a/utbot-instrumentation/src/main/kotlin/org/utbot/instrumentation/instrumentation/InvokeWithStaticsInstrumentation.kt
+++ b/utbot-instrumentation/src/main/kotlin/org/utbot/instrumentation/instrumentation/InvokeWithStaticsInstrumentation.kt
@@ -1,7 +1,7 @@
 package org.utbot.instrumentation.instrumentation
 
 import org.utbot.common.withAccessibility
-import org.utbot.framework.plugin.api.util.field
+import org.utbot.framework.plugin.api.util.jField
 import org.utbot.instrumentation.util.StaticEnvironment
 import java.lang.reflect.Field
 import java.lang.reflect.Modifier
@@ -46,7 +46,7 @@ class InvokeWithStaticsInstrumentation : Instrumentation<Result<*>> {
     private fun setStaticFields(staticEnvironment: StaticEnvironment?) {
         staticEnvironment?.run {
             listOfFields.forEach { (fieldId, value) ->
-                fieldId.field.run {
+                fieldId.jField.run {
                     withAccessibility {
                         set(null, value)
                     }
diff --git a/utbot-sample/src/main/java/org/utbot/examples/objects/HiddenFieldAccessModifiersExample.java b/utbot-sample/src/main/java/org/utbot/examples/objects/HiddenFieldAccessModifiersExample.java
new file mode 100644
index 0000000000..16cf7f50b9
--- /dev/null
+++ b/utbot-sample/src/main/java/org/utbot/examples/objects/HiddenFieldAccessModifiersExample.java
@@ -0,0 +1,7 @@
+package org.utbot.examples.objects;
+
+public class HiddenFieldAccessModifiersExample {
+    public boolean checkSuperFieldEqualsOne(HiddenFieldAccessModifiersSucc b) {
+        return b.getF() == 1;
+    }
+}
diff --git a/utbot-sample/src/main/java/org/utbot/examples/objects/HiddenFieldAccessModifiersSucc.java b/utbot-sample/src/main/java/org/utbot/examples/objects/HiddenFieldAccessModifiersSucc.java
new file mode 100644
index 0000000000..ba200f176f
--- /dev/null
+++ b/utbot-sample/src/main/java/org/utbot/examples/objects/HiddenFieldAccessModifiersSucc.java
@@ -0,0 +1,5 @@
+package org.utbot.examples.objects;
+
+public class HiddenFieldAccessModifiersSucc extends HiddenFieldAccessModifiersSuper {
+    private int f;
+}
diff --git a/utbot-sample/src/main/java/org/utbot/examples/objects/HiddenFieldAccessModifiersSuper.java b/utbot-sample/src/main/java/org/utbot/examples/objects/HiddenFieldAccessModifiersSuper.java
new file mode 100644
index 0000000000..1d819d711d
--- /dev/null
+++ b/utbot-sample/src/main/java/org/utbot/examples/objects/HiddenFieldAccessModifiersSuper.java
@@ -0,0 +1,11 @@
+package org.utbot.examples.objects;
+
+public class HiddenFieldAccessModifiersSuper {
+    public int f;
+    public int getF() {
+        return this.f;
+    }
+    public void setF(int val) {
+        this.f = val;
+    }
+}