Object Class

Contains methods that are implemented by all Apex types.

System

All Apex classes have the Object class as the base class, and therefore implement all the Object class methods.

The following are methods for Object.

  • equals(obj)

    Compares an object to the specified object and returns true if both are equal. Otherwise, returns false.

  • hashCode()

    Returns a hash code for the object.

  • toString()

    Returns a string that represents the object. The string includes the class name of which the object is an instance, the at (@) character, and the unsigned hexadecimal representation of the object’s hash code value.

Compares an object to the specified object and returns true if both are equal. Otherwise, returns false.

public Boolean equals(Object obj)

  • obj: Type: Object The object with which to compare.

Type: Boolean

If x, y, and z are non-null instances of a class, the equals method must be:

  • Reflexive: x.equals(x)
  • Symmetric: x.equals(y) returns true if and only if y.equals(x) returns true
  • Transitive: If x.equals(y) returns true and y.equals(z) returns true, then x.equals(z) returns true
  • Consistent: Multiple invocations of x.equals(y) consistently return true or consistently return false, provided the objects used in comparison are not modified.
  • For any non-null reference value x, x.equals(null) returns false

Use the equals method in your class to simplify comparision of objects. You can use the == operator to compare objects, or the equals method. For example:

Returns a hash code for the object.

public Integer hashCode()

Type: Integer

  • If the hashCode method is invoked on the same object more than once during execution of an Apex request, it must return the same value.

    • The hash code value is same provided no information used in equals comparisons on the object is modified.
    • The hash code value need not remain consistent from one Apex execution request to another execution of the same application.

  • If two objects are equal, based on the equals method, hashCode must return the same value.

  • If two objects are unequal, based on the result of the equals method, it is not required that hashCode return distinct values.

Returns a string that represents the object. The string includes the class name of which the object is an instance, the at (@) character, and the unsigned hexadecimal representation of the object’s hash code value.

public String toString()

Type: String

In API version 57.0 and later, the toString() method only includes member variables of Apex objects that are visible in the current namespace. Non-global properties are suppressed from output when you invoke toString() on managed Apex types. To keep the non-global state of the object visible in debug output, you can explicitly override the toString() method.