FSInfo.java revision 3155:30e288cb2d22 
1
2package com.sun.tools.javac.file;
3
4import java.io.IOException;
5import java.nio.file.Files;
6import java.nio.file.Path;
7import java.nio.file.Paths;
8import java.util.ArrayList;
9import java.util.Collections;
10import java.util.List;
11import java.util.StringTokenizer;
12import java.util.jar.Attributes;
13import java.util.jar.JarFile;
14import java.util.jar.Manifest;
15
16import com.sun.tools.javac.util.Context;
17
18/**
19 * Get meta-info about files. Default direct (non-caching) implementation.
20 * @see CacheFSInfo
21 *
22 * <p><b>This is NOT part of any supported API.
23 * If you write code that depends on this, you do so at your own risk.
24 * This code and its internal interfaces are subject to change or
25 * deletion without notice.</b>
26 */
27public class FSInfo {
28
29    /** Get the FSInfo instance for this context.
30     *  @param context the context
31     *  @return the Paths instance for this context
32     */
33    public static FSInfo instance(Context context) {
34        FSInfo instance = context.get(FSInfo.class);
35        if (instance == null)
36            instance = new FSInfo();
37        return instance;
38    }
39
40    protected FSInfo() {
41    }
42
43    protected FSInfo(Context context) {
44        context.put(FSInfo.class, this);
45    }
46
47    public Path getCanonicalFile(Path file) {
48        try {
49            return file.toRealPath();
50        } catch (IOException e) {
51            return file.toAbsolutePath().normalize();
52        }
53    }
54
55    public boolean exists(Path file) {
56        return Files.exists(file);
57    }
58
59    public boolean isDirectory(Path file) {
60        return Files.isDirectory(file);
61    }
62
63    public boolean isFile(Path file) {
64        return Files.isRegularFile(file);
65    }
66
67    public List<Path> getJarClassPath(Path file) throws IOException {
68        Path parent = file.getParent();
69        try (JarFile jarFile = new JarFile(file.toFile())) {
70            Manifest man = jarFile.getManifest();
71            if (man == null)
72                return Collections.emptyList();
73
74            Attributes attr = man.getMainAttributes();
75            if (attr == null)
76                return Collections.emptyList();
77
78            String path = attr.getValue(Attributes.Name.CLASS_PATH);
79            if (path == null)
80                return Collections.emptyList();
81
82            List<Path> list = new ArrayList<>();
83
84            for (StringTokenizer st = new StringTokenizer(path);
85                 st.hasMoreTokens(); ) {
86                String elt = st.nextToken();
87                Path f = Paths.get(elt);
88                if (!f.isAbsolute() && parent != null)
89                    f = parent.resolve(f).toAbsolutePath();
90                list.add(f);
91            }
92
93            return list;
94        }
95    }
96}
97