I am writing a test case using JUnit and the method under test takes a final class with a private constructor as a parameter. Since I cannot instantiate it with the new keyword I tried using Mockito but found out that Mockito doesn’t like final class. I went to use PowerMockito which seemed reasonable to me but PowerMockito.mockStatic(Field.class); is a void method and I need a reference of Field so that I can pass it as an argument while invoking the method.
I want to catch IllegalArgumentException but first I need to pass reference of Field as an argument
Method under test
public boolean accept(Field field) {
if( ignoreNulls ) {
try {
if( field.get( super.getObject() ) == null ) {
return false;
}
} catch (IllegalArgumentException e) {
} catch (IllegalAccessException e) {
}
}
return super.accept(field);
}
JUnit test case
@Test(expected=IllegalArgumentException.class)
public void testAccept() throws Exception {
DefaultToStringBuilder builder = new DefaultToStringBuilder(new Object());
PowerMockito.mockStatic(Field.class);
builder.accept(?);
}
I am not sure how should I be doing this.
Thanks in advance
解决方案
We can actually use Core Java to achieve this. Code below shows how to do it.
private Field field;
@Test(expected=IllegalArgumentException.class)
public void testAccept() throws Exception {
Class> clazz = Field.class;
Constructor> [] constructors = clazz.getDeclaredConstructors();
for(Constructor cons: constructors) {
cons.setAccessible(true);
field = (Field) cons.newInstance();
}
DefaultToStringBuilder builder = new DefaultToStringBuilder(new Object());
builder.accept(field);
assertNotNull(builder);
}