Set field value with reflection

by

Hope this is something what you are trying to do :

import java.lang.reflect.Field;
import java.util.HashMap;
import java.util.Map;
import java.util.concurrent.ConcurrentHashMap;

public class Test {

    private Map ttp = new HashMap(); 

    public  void test() {
        Field declaredField =  null;
        try {

            declaredField = Test.class.getDeclaredField("ttp");
            boolean accessible = declaredField.isAccessible();

            declaredField.setAccessible(true);

            ConcurrentHashMap<Object, Object> concHashMap = new ConcurrentHashMap<Object, Object>();
            concHashMap.put("key1", "value1");
            declaredField.set(this, concHashMap);
            Object value = ttp.get("key1");

            System.out.println(value);

            declaredField.setAccessible(accessible);

        } catch (NoSuchFieldException 
                | SecurityException
                | IllegalArgumentException 
                | IllegalAccessException e) {
            e.printStackTrace();
        }

    }

    public static void main(String... args) {
        Test test = new Test();
        test.test(); 
    }
}

It prints :

value1

More Related Contents:

  1. How to read the value of a private field from a different class in Java?
  2. Retrieve only static fields declared in Java class
  3. How can I improve performance of Field.set (perhap using MethodHandles)?
  4. How do I invoke a Java method when given the method name as a string?
  5. Getting the name of the currently executing method
  6. Why are my fields initialized to null or to the default value of zero when I’ve declared and initialized them in my class’ constructor?
  7. Any way to Invoke a private method?
  8. Can a Java class add a method to itself at runtime?
  9. Can I get information about the local variables using Java reflection?
  10. Retrieving the inherited attribute names/values using Java Reflection
  11. How to limit setAccessible to only “legitimate” uses?
  12. Get declared fields of java.lang.reflect.Fields in jdk12
  13. Java Reflection: How can I get the all getter methods of a java class and invoke them
  14. How do I find out what type each object is in a ArrayList?
  15. How to use URLClassLoader to load a *.class file?
  16. Is there something like instanceOf(Class c) in Java?
  17. How to get annotations of a member variable?
  18. Java reflection: how to get field value from an object, not knowing its class
  19. How to get the parameter names of an object’s constructors (reflection)? [duplicate]
  20. Java Reflection calling constructor with primitive types
  21. Java Lombok: Omitting one field in @AllArgsConstructor?
  22. Proguard and reflection in Android
  23. Java reflection – impact of setAccessible(true)
  24. Determine if a Class implements a interface in Java
  25. How do I iterate over class members?
  26. How to get all imports defined in a class using java reflection?
  27. How do I print the method body reflectively?
  28. Java introspection and reflection
  29. Get jar version in runtime
  30. ElementType.LOCAL_VARIABLE annotation type

Leave a Comment