In this example we shall show you how to use a null safe equals method to compare objects. To use a null safe equals method to compare objects we have performed the following steps:
- We have created an
abstractclass,ObjectUtilsthat has astaticmethodboolean nullSafeEquals(Object o1, Object o2)that determines if two objects are equal. If the two objects are equal it returnstrue, if one of them isnullit returnsfalse. Then it checks if the two obejcts are instances of any kind of array, eg.Object[],boolean[]etc. Then it usesequals()API method of Arrays to determine if the two arrays are equal. - We have also created a class
A, that has an int and a String field, and overridesequals(Object o)API method of Object. In this method an instance of the class A is compared to an object. If the given object is also instance ofAand its fields are equal to the object’s fields, then true is returned. - We create two new instances of A, with different parameters and call the
nullSafeEquals(Object o1, Object o2)method, in classNullSafeEqualsthat extendsObjectUtils,
as described in the code snippet below.
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Output:
false
This was an example of how to use a null safe equals method to compare objects in Java.
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