How to Modify Annotation Parameter Values at Runtime
Problem Statement
Consider a compiled class with an annotation defined as follows:
Without altering the source code, can we modify the value of "someProperty" at runtime to a different value, such that subsequent reflection will retrieve the updated value instead of the default?
Solution
Disclaimer: The solution may not be applicable on all platforms (e.g., macOS).
Approach:
Leveraging Java's annotation reflection mechanism, we can dynamically modify the underlying annotation values by manipulating its internal data structures.
Code:
Usage Example:
Advantages:
- No need to create a new annotation instance
- Does not require prior knowledge of the concrete annotation class
- Minimal side effects as it operates on the original annotation instance
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