oracle/graal · error · IllegalArgumentException

Reclaimed JNI reference: <this>

Error message

Reclaimed JNI reference: <this>

What it means

Error "Reclaimed JNI reference: <this>" thrown in oracle/graal.

Source

Thrown at sdk/src/org.graalvm.jniutils/src/org/graalvm/jniutils/HSObject.java:149

     *
     * @return the number of objects in the list
     */
    static int invalidate(HSObject head) {
        HSObject o = head;
        int count = 0;
        while (o != null) {
            HSObject next = o.next;
            // Makes the handle now invalid.
            o.next = o;
            o = next;
            count++;
        }
        return count;
    }

    public final JObject getHandle() {
        if (next == this) {
            throw new IllegalArgumentException("Reclaimed JNI reference: " + this);
        }
        return handle;
    }

    @Override
    public String toString() {
        return String.format("%s[0x%x]", getClass().getSimpleName(), handle.rawValue());
    }

    public final void release(JNIEnv env) {
        if (cleaner != null) {
            assert next == null || next == this;
            this.next = this;
            cleaner.clean(env);
        }
    }

    /**

View on GitHub (pinned to a66e9ccd1d)

Solutions

1. Fix the condition reported by the error: Reclaimed JNI reference: <this>
2. Check the throwing call site and ensure its documented preconditions (argument values, types, environment, or configuration) are satisfied before the call.

Example fix

Validate inputs and environment so that the failing condition does not occur: Reclaimed JNI reference: <this>

When it happens

Trigger: Thrown at sdk/src/org.graalvm.jniutils/src/org/graalvm/jniutils/HSObject.java:149 when the library encounters an invalid state.

Common situations: Occurs when a caller violates the contract guarded by this check: Reclaimed JNI reference: <this>

AI-assisted analysis of oracle/graal@a66e9ccd1d (2026-08-14). Data as JSON: /api/errors/0ba8235c41970115. Report an issue: GitHub.