The Java™ Tutorials
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The HighScorePermission Class
Trail: Security Features in Java SE
Lesson: Implementing Your Own Permission

The HighScorePermission Class

The HighScorePermission class defines the permission that ExampleGame needs to update the user's high score.

All permission classes should subclass from either or The basic difference between the two is that defines more complex permissions that require names and actions. For example, a extends from, and requires a name (a filename), and actions allowed for that file (read/write/delete).

In contrast, defines simpler permissions that only require a name. For example, java.lang.RuntimePermission extends from 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 from

Often, the method implementations in the BasicPermission class itself do not need to be overridden by its subclasses. That is the case with our HighScorePermission, so all we need to implement are the constructors, which just invoke the superclass constructors, as shown in the following:

package com.scoredev.scores;


public final class HighScorePermission extends BasicPermission {

    public HighScorePermission(String 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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