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
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
|
/* Copyright 2016 Software Freedom Conservancy Inc.
*
* This software is licensed under the GNU Lesser General Public License
* (version 2.1 or later). See the COPYING file in this distribution.
*/
//
// PhotoFileAdapter
//
// PhotoFileAdapter (and its immediate children, PhotoFileReader and PhotoFileWriter) are drivers
// hiding details of reading and writing image files and their metadata. They should keep
// minimal state beyond the filename, if any stat at all. In particular, they should avoid caching
// values, especially the readers, as writers may be created at any time and invalidate that
// information, unless the readers monitor the file for these changes.
//
// PhotoFileAdapters should be entirely thread-safe. They are not, however, responsible for
// atomicity on the filesystem.
//
public abstract class PhotoFileAdapter {
private string filepath;
private PhotoFileFormat file_format;
private File file = null;
protected PhotoFileAdapter(string filepath, PhotoFileFormat file_format) {
this.filepath = filepath;
this.file_format = file_format;
}
public bool file_exists() {
return FileUtils.test(filepath, FileTest.IS_REGULAR);
}
public string get_filepath() {
return filepath;
}
public File get_file() {
File result;
lock (file) {
if (file == null)
file = File.new_for_path(filepath);
result = file;
}
return result;
}
public PhotoFileFormat get_file_format() {
return file_format;
}
}
//
// PhotoFileReader
//
public abstract class PhotoFileReader : PhotoFileAdapter {
public enum Role {
DEFAULT,
THUMBNAIL
}
PhotoFileReader.Role role = Role.DEFAULT;
protected PhotoFileReader(string filepath, PhotoFileFormat file_format) {
base (filepath, file_format);
}
public PhotoFileWriter create_writer() throws PhotoFormatError {
return get_file_format().create_writer(get_filepath());
}
public PhotoFileMetadataWriter create_metadata_writer() throws PhotoFormatError {
return get_file_format().create_metadata_writer(get_filepath());
}
public abstract PhotoMetadata read_metadata() throws Error;
public abstract Gdk.Pixbuf unscaled_read() throws Error;
public virtual Gdk.Pixbuf scaled_read(Dimensions full, Dimensions scaled) throws Error {
return resize_pixbuf(unscaled_read(), scaled, Gdk.InterpType.BILINEAR);
}
public void set_role (PhotoFileReader.Role role) {
this.role = role;
}
public PhotoFileReader.Role get_role () {
return this.role;
}
}
//
// PhotoFileWriter
//
public abstract class PhotoFileWriter : PhotoFileAdapter {
protected PhotoFileWriter(string filepath, PhotoFileFormat file_format) {
base (filepath, file_format);
}
public PhotoFileReader create_reader() {
return get_file_format().create_reader(get_filepath());
}
public abstract void write(Gdk.Pixbuf pixbuf, Jpeg.Quality quality) throws Error;
}
//
// PhotoFileMetadataWriter
//
public abstract class PhotoFileMetadataWriter : PhotoFileAdapter {
protected PhotoFileMetadataWriter(string filepath, PhotoFileFormat file_format) {
base (filepath, file_format);
}
public PhotoFileReader create_reader() {
return get_file_format().create_reader(get_filepath());
}
public abstract void write_metadata(PhotoMetadata metadata) throws Error;
}
|
