I find myself in a situation where it seems I would need to be able to cast an Object that is an array of some other, non-primitive type, into its concrete array type, to pass to a generic. The same thing is trivial to get to work with non-array types: desiredType.cast(o) yields an object of the correct type. Would someone
Tag: reflection
Get Values of variables under an Enum
I want to write into a file/print the constants of an enum, as well as the values of their variables. For example, here is what I thought of doing: However, I am not fully sure on how to do such a thing, as I only recently began working with reflection. This is the code that I currently have. Here is
How to explicitly invoke default method from a dynamic Proxy?
Since Java 8 interfaces could have default methods. I know how to invoke the method explicitly from the implementing method, i.e. (see Explicitly calling a default method in Java) But how do I explicitly invoke the default method using reflection for example on a proxy? Example: Edit: I know a similar question has been asked in How do I invoke
using Constructor without “new” word in java
So I’m trying to learn to use Reflection in java(so i think its called), so I did a little project to make an object without the optimal Constructor pattern with the “new” word. Unfortunately, it shows me an error for the class type array for the constructor. Here is my project: SomeClass.java: } Student.java: } The error: What is the
How have RecursiveToStringStyle and JSON_STYLE using commons-lang3
I’m using the dependency: I have the following objects: And I need to log the content of the class X recursively to get the class Y as well and using the JSON style. That is my goal and this is the purpose of this question. Approach 1: Approach 1 result: Approach 2: Approach 2 result: Successful Approach: Successful Approach result
Automatically delegating all methods of a java class
Say I have a class with many of public methods: Now I would like to create a wrapper class which would delegate all the methods to wrapped instance (delegate): Now if MyClass has a lot of methods I would need to override each of them which is more or less the same code which just “delegates”. I was wondering if
Access a private field for a junit test
I am trying to initialize a private field from a class in order to unit test its methods. For that I am using reflection but I am always getting an IllegalArgumentException and I don’t understand what I am doing wrong. My code looks something like this: I get this error when I am trying to run the test: I also
JSONPath resolver for Java objects
How can I get a value from an Java object instead from a JSON string by applying a JSONPath expression? I receive a Java object that is created from a JSON string (via Jackson, no way to influence it): I further have some JSONPath expressions as Java Strings reflecting values in the object (they might be much more complex): I
Accessing non-visible classes with reflection
I am trying to get an instance of a non-visible class, AKA package private class, using reflection. I was wondering if there was a way to switch the modifiers to make it public and then access it using Class.forName. When I try that now it stops me saying I can’t do it. Unfortunately there is no setAccesible method of the
How to parse a String variable into any data type in Java?
I want to build a method that can convert a String value to a given Field object data type through Java Reflection. Here is my code: String value = …; Class clazz = …