I am trying to obtain a field’s value via reflection. The problem is I don’t know the field’s type and have to decide it while getting the value. This code results with this exception: Can not set java.lang.String field com….fieldName to java.lang.String I tried to cast, but I get compilation errors: or How can I do this? Answer Like answered
Tag: reflection
Is it possible to cast a retrieved Class object (via reflection) to an interface?
I have 3 projects in my workspace – A, B, and C which is an Android lib project. A contains an Activity named Atest B contains a class named Btest which implements interface I. C contains the I interface. Both A and B are installed on my Android device. During Atest runtime, i’m executing the next code: Now here is
Java seek a method with specific annotation and its annotation element
Suppose I have this annotation class So is there a way to look into an object, “seek” out the method with the @MethodXY annotation, where its element x = 3, y = 2, and invoke it? Thanks Answer Here is a method, which returns methods with specific annotations: It can be easily modified to your specific needs. Pls note that
calling numbered function name in loop using java reflection
i have a problem as : MyFirstClass.java MySecondClass.java TestClass.java I want to use java reflection and call the pObj.getP**Param() methods in for loop by providing the parameters to g How it can be made possible. I don’t want to use array of p*Params. Thanks in advance. Answer Are you sure this is what you need? For me, your code seems
Change private static final field using Java reflection
I have a class with a private static final field that, unfortunately, I need to change it at run-time. Using reflection I get this error: java.lang.IllegalAccessException: Can not set static final boolean field Is there any way to change the value? Answer Assuming no SecurityManager is preventing you from doing this, you can use setAccessible to get around private and
How do I programmatically compile and instantiate a Java class?
I have the class name stored in a property file. I know that the classes store will implement IDynamicLoad. How do I instantiate the class dynamically? Right now I have Does the newInstance only load compiled .class files? How do I load a Java Class that is not compiled? Answer How do I load a Java Class that is not
Java – Get a list of all Classes loaded in the JVM
I would like to get a list of all the classes belonging to a certain package as well as all of their children. The classes may or may not be already loaded in the JVM. Answer Well, what I did was simply listing all the files in the classpath. It may not be a glorious solution, but it works reliably
Get type of a generic parameter in Java with reflection
Is it possible to get the type of a generic parameter? An example: Answer One construct, I once stumbled upon looked like So there seems to be some reflection-magic around that I unfortunetly don’t fully understand… Sorry.
Simple way to get wrapper class type in Java
I have a piece of code where I need to pass the class of a field in a method. Because of the mechanics of my code I can only handle reference objects and not primitives. I want an easy way of determining if a Field’s type is primitive and swap it with the appropriate wrapper class. So in code what
Is there a general “back-end” library for Java reflection
I’m currently working with a specialized, interpreted, programming language implemented in Java. As a very small part of the language, I’d like to add the ability to make calls into Java. Before I dive into all of the nitty-gritty of reflection, I was wondering if anyone knew of a general library for doing the “back-end” part of invoking Java code