import java.lang.reflect.*;

public class ReflectUtils {


  public static void main(String[] args) throws Exception{
    TestClass test = new TestClass();

    System.out.println (ReflectUtils.getValueOf(test,"firstValue"));
    System.out.println (ReflectUtils.getValueOf(test,"secondValue"));
    System.out.println (ReflectUtils.getValueOf(test,"thirdValue"));

    /*
    output :
        3.1416
        42
        Hello world
    */
  }

  public static Object getValueOf(Object clazz, String lookingForValue)
       throws Exception {
    Field field = clazz.getClass().getField(lookingForValue);
    Class clazzType = field.getType();
    if (clazzType.toString().equals("double"))
      return field.getDouble(clazz);
    else if (clazzType.toString().equals("int"))
      return field.getInt(clazz);
    // else other type ...
    // and finally
    return field.get(clazz);
  }
}

class TestClass {
  public double firstValue  = 3.1416;
  public int    secondValue = 42;
  public String thirdValue = "Hello world";
}