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I am attempting to do the equivalent of
if ( object1.class == object2.class ) { //do something } which of course doesn't work, what method am I overlooking?
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Java instanceof Operator The instanceof operator in Java is used to check whether an object is an instance of a particular class or not. objectName instanceOf className; Here, if objectName is an instance of className , the operator returns true . Otherwise, it returns false .
Yes, two or more references, say from parameters and/or local variables and/or instance variables and/or static variables can all reference the same object.
No, it never returns true unless you feed it the same exact object reference. The reason for it is that Java objects are not "embedded" in one another: there is a reference to B inside A , but it refers to a completely different object.
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.
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