void setByte (Object obj, byte b) Sets byte field value. void setBoolean (Object obj, boolean z) Sets boolean field value. Note: We have to turn off the java access check for field modifiers. void set (Object obj, Object value) Sets the field value. The get() and set() method are used to get and set public field value in java. as side effect putValue() called that initializes integers the static values are set. (String. If you load a class in two different class loaders these classes can have static fields with different values. We can also set the value back to a field with reflection.
public static getFieldWithAnnotation(Class.I can get the value of a instace variable normally starting from the a instance, since static fields are class variable. Obtains the number value of a DocumentField typed as NUMBER. ("User object has been created using constructor User()") Is it possible to get a value os a static final variable of a class with reflection.
Our test class will be a simple model class having 2 constructors and a few methods for testing.
JAVA REFLECTION GET STATIC FIELD VALUE HOW TO
Here is an example how to execute a method using reflection in Java. Also provides the possibility to instantiate new objects, invoke methods and get/set field values. If the field is a static field, the argument of obj is ignored it may be null Otherwise, the underlying field is an instance field. If Field has a primitive type then the value of the field is automatically wrapped in an object. Reflection allows programmatic access to information about the fields, methods and constructors of loaded classes, and the use of reflected fields, methods, and constructors to operate on their underlying counterparts, within security restrictions. The get () method of used to get the value of the field object. Yet CONST_INT is still available reflectively.Java Reflection provides classes and interfaces for obtaining reflective information about classes and objects. You can see that CONST_INT is inlined, but CONST_STRING and CONST_OBJECT (of course) are not. If you know the type you can use one of the get methods with null (for static fields only, in fact with a static field the argument passed to the get method is ignored entirely). II.2 Access and modify any class variables / Returns an object containing the value of any static field (even private). Try to read the value of a potentially inaccessible static field. First retrieve the field property of the class, then you can retrieve the value. public static final String TEST PropertyFileReader.getProperty ('TEST') This prevents the compiler from optimizing the code, allowing you to tinker with it using Reflection. Test class: public class ReflectionConstantTest Find all fields of the supplied class or interface that match the. You can overcome this behavior by setting the value of the static final field using a method such as: 1. Assuming no SecurityManager is preventing you from doing this, you can use setAccessible to get around private and resetting the modifier to get rid of. I'll find out.Įdit: Yes, you can still access them even if they are inlined. Sun's compiler inlines primitive constants, but I don't know if they remove the entry from the class entirely. The reflected field may be a class variable ( static field) or an. I would guess that it depends on the type and the compiler (on second thought, it had sure better not!). A Field provides information about, and access to, a single field of a class or interface.