Is there a way to find if a Field is boolean the same as isPrimitive()?

Question

Is there a way to find if a Field is boolean in Java reflection the same as isPrimitive()?

Field fieldlist[] = clazz.getDeclaredFields();
for (int i = 0; fieldlist.length & gt; i; i++) {
 Field fld = fieldlist[i];
 if (fld.getClass().isPrimitive()) {
  fld.setInt(object, 0);
  continue;
 }
}

Tudor · Accepted Answer · 2012-01-14T18:30:38.897

33

if(fld.getType().equals(boolean.class))

Just tested this and it works for primitive boolean variables.

edited Jan 14 '12 at 18:30

answered Jan 14 '12 at 18:25

Tudor

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score 2 · Answer 2 · answered Jan 14 '12 at 18:23

2

I believe Boolean.class.isAssignableFrom(fld.getClass()) can be used to determine if the field is a boolean. I haven't had a chance to test whether this works for primitives though.

answered Jan 14 '12 at 18:23

Vala

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This shouldn't work for primitive booleans. If you're using Spring, you can call ClassUtils.isAssignable(Boolean.class, fld.getClass()), though, and that should work if fld is boolean or Boolean. – Dan Robinson Apr 05 '13 at 04:35
Thor84no: I got this error while doing that: The method isAssignableFrom(Class>) in the type Class is not applicable for the arguments (Boolean) – Akshaya Aradhya Jul 11 '14 at 00:09
Dan Robinson: ClassUtils didn't help either: The method isAssignable(Class>, Class>) in the type ClassUtils is not applicable for the arguments (Class, Boolean) – Akshaya Aradhya Jul 11 '14 at 00:14
I believe there should be a `boolean.class` that covers primitives (from Java 6 onward I think). You could combine the two `Boolean.class.isAssignableFrom(fld.getClass()) || boolean.class.isAssignableFrom(fld.getClass())`. I don't have an IDE handy atm though. – Vala Jul 11 '14 at 09:30

score 1 · Answer 3 · edited Nov 25 '13 at 05:23

Try this (reference):

public boolean getBoolean(Object obj)
               throws IllegalArgumentException,
                      IllegalAccessException

Gets the value of a static or instance boolean field.

Parameters:
    obj - the object to extract the boolean value from 
Returns:
    the value of the boolean field 
Throws:
    IllegalAccessException - if the underlying field is inaccessible. 
    IllegalArgumentException - if the specified object is not an instance of the class or interface declaring the underlying field (or a subclass or implementor thereof), **or if the field value cannot be converted to the type boolean** by a widening conversion. 
    NullPointerException - if the specified object is null and the field is an instance field. 
    ExceptionInInitializerError - if the initialization provoked by this method fails.

score 0 · Answer 4 · edited Jul 17 '18 at 15:01

0

This is for primitive and object:

boolean isBooleanType = field.getType().equals(boolean.class) || field.getType().equals(Boolean.class);

edited Jul 17 '18 at 15:01

WhatsThePoint

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answered Jul 17 '18 at 13:58

Rafał Rychlewski

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Is there a way to find if a Field is boolean the same as isPrimitive()?

4 Answers4