Introduce vendor.mime.types
Like mime.types and android.mime.types, this file specifies mappings
between MIME types and file extensions. Unlike those files, it can
only be used to define _additional_ mapping but not modify (change,
remove) any mappings defined by those files.
This is done by prepending '?' to every line element from
vendor.mime.types that doesn't already have one; when there is a
leading "?", it is ignored so that it's okay to move a line from
{android,vendor}.mime.types without necessarily changing it.
Test: Checked manually that vendor.mime.types works as expected.
Specifically, after adding these lines to vendor.mime.type:
audio/mpeg testmpeg
audio/testmpeg mp3
?mime/foo ?fooext
the following test passes:
MimeTypeMap map = MimeTypeMap.getSingleton();
// Original mapping is unchanged
assertEquals("mp3", map.getExtensionFromMimeType("audio/mpeg"));
assertEquals("audio/mpeg", map.getMimeTypeFromExtension("mp3"));
// Map from the key to existing value is added
assertEquals("audio/mpeg", map.getMimeTypeFromExtension("testmpeg"));
assertEquals("mp3", map.getExtensionFromMimeType("audio/testmpeg"));
// Completely new mapping is added both ways
assertEquals("mime/foo", map.getMimeTypeFromExtension("fooext"));
assertEquals("fooext", map.getExtensionFromMimeType("mime/foo"));
Bug: 141842825
Change-Id: Iaf918ce39324709ff58a8e0f9612e4827a673323
diff --git a/mime/java/android/content/type/DefaultMimeMapFactory.java b/mime/java/android/content/type/DefaultMimeMapFactory.java
index 545fb3c..56b234f 100644
--- a/mime/java/android/content/type/DefaultMimeMapFactory.java
+++ b/mime/java/android/content/type/DefaultMimeMapFactory.java
@@ -21,6 +21,7 @@
import java.io.BufferedReader;
import java.io.IOException;
import java.io.InputStreamReader;
+import java.util.ArrayList;
import java.util.Arrays;
import java.util.List;
import java.util.regex.Pattern;
@@ -44,20 +45,17 @@
* Android's default mapping between MIME types and extensions.
*/
public static MimeMap create() {
- return parseFromResources("/mime.types", "/android.mime.types");
+ MimeMap.Builder builder = MimeMap.builder();
+ parseTypes(builder, true, "/mime.types");
+ parseTypes(builder, true, "/android.mime.types");
+ parseTypes(builder, false, "/vendor.mime.types");
+ return builder.build();
}
private static final Pattern SPLIT_PATTERN = Pattern.compile("\\s+");
- static MimeMap parseFromResources(String... resourceNames) {
- MimeMap.Builder builder = MimeMap.builder();
- for (String resourceName : resourceNames) {
- parseTypes(builder, resourceName);
- }
- return builder.build();
- }
-
- private static void parseTypes(MimeMap.Builder builder, String resource) {
+ private static void parseTypes(MimeMap.Builder builder, boolean allowOverwrite,
+ String resource) {
try (BufferedReader r = new BufferedReader(
new InputStreamReader(DefaultMimeMapFactory.class.getResourceAsStream(resource)))) {
String line;
@@ -71,6 +69,12 @@
continue;
}
List<String> specs = Arrays.asList(SPLIT_PATTERN.split(line));
+ if (!allowOverwrite) {
+ // Pretend that the mimeType and each file extension listed in the line
+ // carries a "?" prefix, which means that it can add new mappings but
+ // not modify existing mappings (putIfAbsent() semantics).
+ specs = ensurePrefix("?", specs);
+ }
builder.put(specs.get(0), specs.subList(1, specs.size()));
}
} catch (IOException | RuntimeException e) {
@@ -78,4 +82,15 @@
}
}
+ private static List<String> ensurePrefix(String prefix, List<String> strings) {
+ List<String> result = new ArrayList<>(strings.size());
+ for (String s : strings) {
+ if (!s.startsWith(prefix)) {
+ s = prefix + s;
+ }
+ result.add(s);
+ }
+ return result;
+ }
+
}