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Determine if two Java objects are of the same class

开发者 https://www.devze.com 2023-03-23 07:49 出处:网络
I am attempting to do the equivalent of if ( object1.class == object2.class ) { //do something } which of course does开发者_StackOverflown\'t work, what method am I overlooking?If they\'re from the

I am attempting to do the equivalent of

if ( object1.class == object2.class )
{
    //do something
}  

which of course does开发者_StackOverflown't work, what method am I overlooking?


If they're from the exact same class:

boolean result = object1.getClass().equals( object2.getClass());

Now if they are compatible classes (if one is of a descendent class to the other):

HashMap<String,Object> hashMap = new HashMap<String,Object>();
LinkedHashMap<String,Object> linkedHashMap = new LinkedHashMap<String,Object>();
boolean result = hashMap.getClass().isAssignableFrom( linkedHashMap.getClass() );

As LinkedHashMap is a subclass of HashMap this result variable will be true, so this might probably be better for you as it's going to find exact and subclass matches.

Also, you should avoid using ".class" on variables, as it might not give you the correct result, example:

Object someText = "text value";
System.out.println( someText.class.getName() ); //this will print java.lang.Object and not java.lang.String

When you're using ".class" you're acessing the variable static property and not the class of the object itself.


You're missing the getClass() method,

if (object1.getClass().equals(object2.getClass())) 
{ 
    // do something 
}


object1.getClass() == object2.getClass()


You're looking for the getClass method, defined in java.lang.Class.

(Source: http://download.oracle.com/javase/7/docs/api/java/lang/Class.html)

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