[CAMEL-16943] MainPropertyPlaceholderWithEnvTest failed with JDK17

• Type: Sub-task
• Status: Resolved
• Priority: Major
• Resolution: Fixed
• Fix Version/s: Future
• Component/s: camel-main
• Estimated Complexity: Unknown
• Assignee: Freeman Yue Fang
• Reporter: Freeman Yue Fang
• Created: 10/Sep/21 17:41
• Updated: 19/Apr/22 13:36
• Resolved: 19/Apr/22 13:36

Description

get exception like

Suppressed: java.lang.reflect.InaccessibleObjectException: Unable to make field private final java.util.Map java.util.Collections$UnmodifiableMap.m accessible: module java.base does not "opens java.util" to unnamed module @bf20622
		at java.base/java.lang.reflect.AccessibleObject.checkCanSetAccessible(AccessibleObject.java:354)
		at java.base/java.lang.reflect.AccessibleObject.checkCanSetAccessible(AccessibleObject.java:297)
		at java.base/java.lang.reflect.Field.checkCanSetAccessible(Field.java:178)
		at java.base/java.lang.reflect.Field.setAccessible(Field.java:172)
		at org.apache.camel.main.MainPropertyPlaceholderWithEnvTest.getFieldValue(MainPropertyPlaceholderWithEnvTest.java:276)
		at org.apache.camel.main.MainPropertyPlaceholderWithEnvTest.getEditableMapOfVariables(MainPropertyPlaceholderWithEnvTest.java:226)
		at org.apache.camel.main.MainPropertyPlaceholderWithEnvTest.doEnvVariable(MainPropertyPlaceholderWithEnvTest.java:206)
		at org.apache.camel.main.MainPropertyPlaceholderWithEnvTest.tearDown(MainPropertyPlaceholderWithEnvTest.java:182)
		at java.base/jdk.internal.reflect.NativeMethodAccessorImpl.invoke0(Native Method)
		at java.base/jdk.internal.reflect.NativeMethodAccessorImpl.invoke(NativeMethodAccessorImpl.java:77)
		at java.base/jdk.internal.reflect.DelegatingMethodAccessorImpl.invoke(DelegatingMethodAccessorImpl.java:43)
		at java.base/java.lang.reflect.Method.invoke(Method.java:568)

This is because System.getEnv() returns a java.util.Collections$UnmodifiableMap which isn't supposed to be changed during runtime code. To workaround this, normally we need to use reflection way to make a private field in java.util.Collections$UnmodifiableMap accessible.

But this is kind of against the encapsulation(Strongly Encapsulate JDK Internals ) rule of java Modules since JDK9. Before JDK17, it is it possible to access internal APIs via the --illegal-access command line option which is enabled by default. However, since JDK17 this --illegal-access is removed and we need to either explicitly use --add-opens modules to enable deep reflection for JDK internal code, or we need to get rid of the way to use JDK Internals