# devopsgym / testgen__fasterxml__jackson-databind-4087 - taskset: [devopsgym](https://harnessreport.com/tasks/devopsgym.md) - difficulty: hard - category: test-generation - language: - runnable from the site: no - agent timeout: 3000s ## Results by harness _none yet_ ## Instruction ``` The following text contains a user issue (in <issue/> brackets) posted at a repository. Further, you are provided with file contents of several files in the repository that contain relevant code (in <code> brackets). It may be necessary to use code from third party dependencies or files not contained in the attached documents however. Your task is to identify the issue and implement a test case that verifies a proposed solution to this issue. More details at the end of this text. <issue> ### Search before asking - [X] I searched in the [issues](https://github.com/FasterXML/jackson-databind/issues) and found nothing similar. ### Describe the bug Please consider the following trivial Java code: ```java package org.myapp; import com.fasterxml.jackson.databind.ObjectMapper; import java.util.OptionalInt; public class Main { public static void main(final String[] args) throws Exception { final ObjectMapper objectMapper = new ObjectMapper(); final String json = "{ }"; // empty final Data data = objectMapper.readValue(json, Data.class); System.out.println("Read data: " + data); } public static class Data { private OptionalInt value; public Data() { } public void setValue(OptionalInt i) { this.value = i; } public OptionalInt getValue() { return this.value; } @Override public String toString() { return "Data[value=" + this.value + "]"; } } } ``` When using `jackson-databind` `2.15.2` and Java version 17 and running this program, it results in: ```console Caused by: java.lang.reflect.InaccessibleObjectException: Unable to make private java.util.OptionalInt() accessible: module java.base does not "opens java.util" to unnamed module @4cf328c3 at java.lang.reflect.AccessibleObject.throwInaccessibleObjectException (AccessibleObject.java:387) at java.lang.reflect.AccessibleObject.checkCanSetAccessible (AccessibleObject.java:363) at java.lang.reflect.AccessibleObject.checkCanSetAccessible (AccessibleObject.java:311) at java.lang.reflect.Constructor.checkCanSetAccessible (Constructor.java:192) at java.lang.reflect.Constructor.setAccessible (Constructor.java:185) at com.fasterxml.jackson.databind.util.ClassUtil.checkAndFixAccess (ClassUtil.java:995) at com.fasterxml.jackson.databind.deser.impl.CreatorCollector._fixAccess (CreatorCollector.java:278) at com.fasterxml.jackson.databind.deser.impl.CreatorCollector.setDefaultCreator (CreatorCollector.java:130) at com.fasterxml.jackson.databind.deser.BasicDeserializerFactory._addExplicitConstructorCreators (BasicDeserializerFactory.java:438) at com.fasterxml.jackson.databind.deser.BasicDeserializerFactory._constructDefaultValueInstantiator (BasicDeserializerFactory.java:293) at com.fasterxml.jackson.databind.deser.BasicDeserializerFactory.findValueInstantiator (BasicDeserializerFactory.java:222) at com.fasterxml.jackson.databind.deser.BeanDeserializerFactory.buildBeanDeserializer (BeanDeserializerFactory.java:262) at com.fasterxml.jackson.databind.deser.BeanDeserializerFactory.createBeanDeserializer (BeanDeserializerFactory.java:151) at com.fasterxml.jackson.databind.deser.DeserializerCache._createDeserializer2 (DeserializerCache.java:415) at com.fasterxml.jackson.databind.deser.DeserializerCache._createDeserializer (DeserializerCache.java:350) at com.fasterxml.jackson.databind.deser.DeserializerCache._createAndCache2 (DeserializerCache.java:264) at com.fasterxml.jackson.databind.deser.DeserializerCache._createAndCacheValueDeserializer (DeserializerCache.java:244) at com.fasterxml.jackson.databind.deser.DeserializerCache.findValueDeserializer (DeserializerCache.java:142) at com.fasterxml.jackson.databind.DeserializationContext.findNonContextualValueDeserializer (DeserializationContext.java:644) at com.fasterxml.jackson.databind.deser.BeanDeserializerBase.resolve (BeanDeserializerBase.java:539) at com.fasterxml.jackson.databind.deser.DeserializerCache._createAndCache2 (DeserializerCache.java:294) at com.fasterxml.jackson.databind.deser.DeserializerCache._createAndCacheValueDeserializer (DeserializerCache.java:244) at com.fasterxml.jackson.databind.deser.DeserializerCache.findValueDeserializer (DeserializerCache.java:142) at com.fasterxml.jackson.databind.DeserializationContext.findRootValueDeserializer (DeserializationContext.java:654) at com.fasterxml.jackson.databind.ObjectMapper._findRootDeserializer (ObjectMapper.java:4956) at com.fasterxml.jackson.databind.ObjectMapper._readMapAndClose (ObjectMapper.java:4826) at com.fasterxml.jackson.databind.ObjectMapper.readValue (ObjectMapper.java:3772) at com.fasterxml.jackson.databind.ObjectMapper.readValue (ObjectMapper.java:3740) at org.myapp.Main.main (Main.java:10) ``` So `com.fasterxml.jackson.databind.util.ClassUtil` is trying to `setAccessible()` on the private constructor of a JDK class `java.util.OptionalInt`. One way to solve this issue is to configure the `ObjectMapper` instance as follows: ```java objectMapper.configure(MapperFeature.CAN_OVERRIDE_ACCESS_MODIFIERS, false); ``` However, while looking at the code in `com.fasterxml.jackson.databind.util.ClassUtil` I noticed that there's a specific logic which tries to not `setAccessible()` on JDK internal classes here https://github.com/FasterXML/jackson-databind/blob/jackson-databind-2.15.2/src/main/java/com/fasterxml/jackson/databind/util/ClassUtil.java#L994 which looks like: ```java if (!isPublic || (evenIfAlreadyPublic && !isJDKClass(declaringClass))) { ao.setAccessible(true); } ``` Should that `!isJDKClass(declaringClass)` be perhaps applied even when `evenIfAlreadyPublic` is false? Something like: ```java if (!isJDKClass(declaringClass) && (!isPublic || evenIfAlreadyPublic)) { ao.setAccessible(true); } ``` That way, it won't try to access the internal JDK classes and run into these exceptions on Java 17+? ### Version Information 2.15.2 ### Reproduction _No response_ ### Expected behavior _No response_ ### Additional context _No response_ </issue> Please generate test cases that check whether an implemented solution resolves the issue of the user (at the top, within <issue/> brackets). You may apply changes to several files. Apply as much reasoning as you please and see necessary. Make sure to implement only test cases and don't try to fix the issue itself. You are not allowed to read git history. ``` --- Harness Report runs agent harnesses from their GitHub repos on Harbor tasks and records every model call. Every page is also `.md` and `.json`; index: https://harnessreport.com/llms.txt · MCP: https://harnessreport.com/mcp