/**
* Returns the value of a given {@link Field} from an {@link Object}. Or null if the {@link
* Object} doesn't have a {@link Field} with the given name.
*
* @param <T> The type of the value
* @param object The {@link Object} whose value is being retrieved
* @param fieldName The name of the {@link Field}
* @return The value of the {@link Field}
*/
@SuppressWarnings("unchecked")
public static <T> T getFieldValue(Object object, String fieldName) {
Field field = ReflectionUtils.getField(object.getClass(), fieldName);
field.setAccessible(true);
try {
return (T) field.get(object);
} catch (Exception ex) {
return null;
}
}
/**
* Set a value in the given object without using getters or setters
*
* @param object The object where we want to null the expression
* @param expression The expression we want to null
* @param value The new value to set
*/
public static void set(Object object, String expression, Object value) {
Field field = ReflectionUtils.getField(object.getClass(), expression);
field.setAccessible(true);
try {
field.set(object, value);
} catch (SecurityException e) {
throw new UnexpectedException(e);
} catch (IllegalArgumentException e) {
throw new UnexpectedException(e);
} catch (IllegalAccessException e) {
throw new UnexpectedException(e);
} finally {
field.setAccessible(false);
}
}
/**
* Returns a {@link Field} from a class or any of its super classes.
*
* @param clazz The Class whose {@link Field} is looked for
* @param fieldName The name of the {@link Field} to get
* @return The {@link Field}
*/
public static Field getField(Class<?> clazz, String fieldName) {
try {
return clazz.getDeclaredField(fieldName);
} catch (NoSuchFieldException e) {
// If the field wasn't found in the object class, its superclass must
// be checked
if (clazz.getSuperclass() != null) {
return ReflectionUtils.getField(clazz.getSuperclass(), fieldName);
}
// If the field wasn't found and the object doesn't have a
// superclass, an exception is thrown
throw new UnexpectedException(
"The class '" + clazz.getName() + "' doesn't have a field named '" + fieldName + "'.");
}
}