FileLocation is a superinterface for all file location types that can be represented under this interface.
A file location specifies the location of a file. The manners of how the file should be accessed depends on the type of the file location and is the responsibility of the consumer.
When using file locations, you shouldn't downcast them or use instanceof
, but use the
accept(
Clients shouldn't implement this interface.
You can create a new FileLocation by using the create
methods of the actual subinterfaces.
public void | accept( Accepts a visitor and calls an appropriate visit method on it. |
public boolean | Indicates whether some other object is "equal to" this one. |
public int | hashCode() Returns a hash code value for the object. |
visit
method on it.null
.
The equals
method implements an equivalence relation on non-null object references:
- It is reflexive: for any non-null reference value
x
,x.equals(x)
should returntrue
. - It is symmetric: for any non-null reference values
x
andy
,x.equals(y)
should returntrue
if and only ify.equals(x)
returnstrue
. - It is transitive: for any non-null reference values
x
,y
, andz
, ifx.equals(y)
returnstrue
andy.equals(z)
returnstrue
, thenx.equals(z)
should returntrue
. - It is consistent: for any non-null reference values
x
andy
, multiple invocations ofx.equals(y)
consistently returntrue
or consistently returnfalse
, provided no information used inequals
comparisons on the objects is modified. - For any non-null reference value
x
,x.equals(null)
should returnfalse
.
The equals
method for class Object
implements the most discriminating possible equivalence
relation on objects; that is, for any non-null reference values x
and y
, this method returns
true
if and only if x
and y
refer to the same object (x == y
has the value
true
).
Note that it is generally necessary to override the hashCode
method whenever this method is overridden,
so as to maintain the general contract for the hashCode
method, which states that equal objects must have
equal hash codes.
true
if this object is the same as the obj argument; false
otherwise.
The general contract of hashCode
is:
- Whenever it is invoked on the same object more than once during an execution of a Java application, the
hashCode
method must consistently return the same integer, provided no information used inequals
comparisons on the object is modified. This integer need not remain consistent from one execution of an application to another execution of the same application. - If two objects are equal according to the
equals(Object)
method, then calling thehashCode
method on each of the two objects must produce the same integer result. - It is not required that if two objects are unequal according to the
Object.equals(
Object) method, then calling thehashCode
method on each of the two objects must produce distinct integer results. However, the programmer should be aware that producing distinct integer results for unequal objects may improve the performance of hash tables.
As much as is reasonably practical, the hashCode method defined by class Object
does return distinct
integers for distinct objects. (This is typically implemented by converting the internal address of the object
into an integer, but this implementation technique is not required by the Java™ programming language.)