1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
package Torello.Java;

/**
 * Thrown when a <CODE>FileNode</CODE> operation has been invoked on an instance that represents
 * an Operating-System <B><CODE>File</CODE></B>, but that invoked-method may only be applied to
 * Operating-System <B><CODE>Directory</CODE></B> instances.  This is a {@code RuntimeException},
 * not a checked-exception.
 *
 * <BR /><BR /><EMBED CLASS='external-html' DATA-FILE-ID=EXPM>
 */
public class DirExpectedException extends FileNodeException
{
    /** <EMBED CLASS='external-html' DATA-FILE-ID=SVUIDEX>  */
    public static final long serialVersionUID = 1;

    /**
     * <EMBED CLASS='external-html' DATA-FILE-ID=EXPF>
     * 
     * <BR /><BR />This {@code public final} field contains the {@code FileNode} that caused an
     * exception to throw.
     */
    public final FileNode fn;

    /**
     * Constructs a new exception with the specified detail message, and one {@code public, final} 
     * parameter: {@code fn}.
     * 
     * @param message This is any message informing the user what has occurred.
     * 
     * @param fn This is the instance of {@code class FileNode} that was involved in the mistake.
     * 
     * <EMBED CLASS='external-html' DATA-FILE-ID=EXPF_PARAM>
     * 
     * @throws ExceptionCheckError If parameter {@code 'fn'} is passed null
     * 
     * @see #fn
     */
    public DirExpectedException(String message, FileNode fn)
    {
        super(message);
        this.fn = fn;

        if (this.fn == null) throw new ExceptionCheckError
            ("DirExpectedException constructor parameter 'fn' was passed null");
    }


    /**
     * Constructs a new exception with the specified detail message, cause-chain 
     * {@code Throwable}, and one {@code public, final} parameter: {@code fn}.
     * 
     * <BR /><BR /><DIV CLASS=JDHint>
     * <B STYLE='color:red;'>Note:</B> The detail message associated with cause is not
     * automatically incorporated into this exception's detail message.
     * </DIV>
     * 
     * @param message This is any message informing the user what has occurred.
     * 
     * @param cause This parameter may be used when generating "multiple-exceptions" that are
     * modified as they are thrown.
     * 
     * @param fn This is the instance of {@code class FileNode} that was involved in the mistake.
     * 
     * <EMBED CLASS='external-html' DATA-FILE-ID=EXPF_PARAM>
     * 
     * @throws ExceptionCheckError If parameter {@code 'fn'} is passed null
     * 
     * @see #fn
     */
    public DirExpectedException(String message, Throwable cause, FileNode fn)
    { 
        super(message, cause);
        this.fn = fn;

        if (this.fn == null) throw new ExceptionCheckError
            ("DirExpectedException constructor parameter 'fn' was passed null");
    }

    /**
     * Checks whether or not the {@code FileNode} parameter passed is actually one representing a 
     * directory, not a file.
     * 
     * @param fn This may be any instance of {@code FileNode} however if it is not one that is
     * meaning to represent an operating-system directory, then this method will automatically
     * throw an exception.
     * 
     * @throws DirExpectedException If parameter {@code 'fn'} is a file, not a directory.
     */
    public static void check(FileNode fn)
    {
        if (! fn.isDirectory) throw new DirExpectedException(
            "The invokation of the previous method on a FileNode that is, itself, a file and " +
            "not a directory cannot proceed.",
            fn
        );
    }
}