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TheHighScorePermission
class defines the permission thatTerrysGame
needs to update the user's high score.All permission classes should subclass from either
java.security.Permission
orjava.security.BasicPermission
. The basic difference between the two is thatjava.security.Permission
defines more complex permissions that require names and actions. For example, ajava.io.FilePermission
extends fromjava.security.Permission
, and requires a name (a filename), and actions allowed for that file (read/write/delete).In contrast,
java.security.BasicPermission
defines simpler permissions that only require a name. For example,java.lang.RuntimePermission
extends fromjava.security.BasicPermission
and simply needs a name (like "exitVM"), which allows programs to exit the Java Virtual Machine.Our
HighScorePermission
is a simple permission, and hence can be extended fromjava.security.BasicPermission
.Often, the method implementations in the
BasicPermission
class itself do not need to be overridden by its subclasses. That is the case with ourHighScorePermission
, so all we need to implement are the constructors, which just invoke the superclass constructors, as shown in thefollowing
:
package com.scoredev.scores; import java.security.*; public final class HighScorePermission extends BasicPermission { public HighScorePermission(String name) { super(name); } // note that actions is ignored and not used, // but this constructor is still needed public HighScorePermission(String name, String actions) { super(name, actions); } }
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