Check if a Class Object is subclass of another Class Object in Java

You want this method:

boolean isList = List.class.isAssignableFrom(myClass);

where in general, List (above) should be replaced with superclass and myClass should be replaced with subclass

From the JavaDoc:

Determines if the class or interface represented by this Class object is either the same as, or is a superclass or superinterface of, the class or interface represented by the specified Class parameter. It returns true if so; otherwise it returns false. If this Class object represents a primitive type, this method returns true if the specified Class parameter is exactly this Class object; otherwise it returns false.

Reference:


Related:

a) Check if an Object is an instance of a Class or Interface (including subclasses) you know at compile time:

boolean isInstance = someObject instanceof SomeTypeOrInterface;

Example:

assertTrue(Arrays.asList("a", "b", "c") instanceof List<?>);

b) Check if an Object is an instance of a Class or Interface (including subclasses) you only know at runtime:

Class<?> typeOrInterface = // acquire class somehow
boolean isInstance = typeOrInterface.isInstance(someObject);

Example:

public boolean checkForType(Object candidate, Class<?> type){
    return type.isInstance(candidate);
}

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