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19
20
21
22 package org.apache.james.context;
23
24 /**
25 * This class is a placeholder for Avalon Context keys.
26 *
27 * In order to decouple James from Phoenix, and to allow James
28 * to run in any Avalon Framework container it is necessary that
29 * James not depend on the BlockContext class from Phoenix, but
30 * rather only on the Context interface. This requires that we
31 * look up context values directly, using String keys. This
32 * class stores the String keys that are used by James to
33 * look up context values.
34 *
35 * The lifetime of this class is expected to be limited. At some
36 * point in the near future the Avalon folks will make a decision
37 * about how exactly to define, describe, and publish context
38 * values. At that point we can replace this temporary mechanism
39 * with the Avalon mechanism. Unfortunately right now that decision
40 * is still unmade, so we need to use this class as a temporary
41 * solution.
42 */
43 public class AvalonContextConstants {
44
45 /**
46 * Private constructor to prevent instantiation or subclassing
47 */
48 private AvalonContextConstants() {}
49
50 /**
51 * The context key associated with the home directory of the application
52 * being run. The object returned on a
53 * context.get(AvalonContextConstants.APPLICATION_HOME) should be of
54 * type <code>java.io.File</code> and should be the home directory
55 * for the application (in our case, James)
56 */
57 public static final String APPLICATION_HOME = "app.home";
58 }