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TheHighScorePermissionclass defines the permission thatTerrysGameneeds to update the user's high score.All permission classes should subclass from either
java.security.Permissionorjava.security.BasicPermission. The basic difference between the two is thatjava.security.Permissiondefines more complex permissions that require names and actions. For example, ajava.io.FilePermissionextends fromjava.security.Permission, and requires a name (a filename), and actions allowed for that file (read/write/delete).In contrast,
java.security.BasicPermissiondefines simpler permissions that only require a name. For example,java.lang.RuntimePermissionextends fromjava.security.BasicPermissionand simply needs a name (like "exitVM"), which allows programs to exit the Java Virtual Machine.Our
HighScorePermissionis a simple permission, and hence can be extended fromjava.security.BasicPermission.Often, the method implementations in the
BasicPermissionclass 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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