dain / parameternames

Parameter Names

Parameter Names contains utility methods for fetching the parameter names for a method or constructor.

Java 8 added the ability to access the parameter names of a method or constructor, but this only works if the code was compiled with the Java 8 version of javac with the -parameters option enabled. This utility falls back to reading parameters from the debug symbols in the method bytecode for classes compiled without the -parameters option enabled.

Usage

Simply, pass java.lang.reflect.Method or java.lang.reflect.Constructor to ParameterNames.getParameterNames. For example:

    Method method = ParameterNames.class.getMethod("getParameterNames", Executable.class);
    List<String> parameterNames = ParameterNames.getParameterNames(method);

Parameter names are loaded in the following order:

1. Java 8 reflection names created by javac with the -parameters option
2. Bytecode debug symbols created by javac with the -g option
3. Default name of argN where N is the index of the parameter starting from zero

Maven Dependency

<dependency>
    <groupId>io.airlift</groupId>
    <artifactId>parameternames</artifactId>
    <version>1.0</version>
</dependency>

License

Parameter Names is released under the Apache License, Version 2.0.