Filter Alias which points non-existing font family name

The FontFamily will be removed if none of font files exist on the
device.

Bug: 192479819
Test: atest FontListParserTest
Change-Id: I36f6476fe37bc04ec8737936747385c63908d651
(cherry picked from commit 691cfe8818513e576300cdb963a65341984659c4)

1 files changed, 37 insertions, 2 deletions

diff --git a/graphics/java/android/graphics/FontListParser.java b/graphics/java/android/graphics/FontListParser.java
index 93a336e7a408..96b33259e739 100644
--- a/graphics/java/android/graphics/FontListParser.java
+++ b/graphics/java/android/graphics/FontListParser.java
@@ -25,6 +25,7 @@ import android.graphics.fonts.FontVariationAxis;
 import android.os.Build;
 import android.os.LocaleList;
 import android.text.FontConfig;
+import android.util.ArraySet;
 import android.util.Xml;
 
 import org.xmlpull.v1.XmlPullParser;
@@ -37,6 +38,7 @@ import java.io.InputStream;
 import java.util.ArrayList;
 import java.util.List;
 import java.util.Map;
+import java.util.Set;
 import java.util.regex.Pattern;
 
 /**
@@ -120,7 +122,23 @@ public class FontListParser {
         }
     }
 
-    private static FontConfig readFamilies(
+    /**
+     * Parses the familyset tag in font.xml
+     * @param parser a XML pull parser
+     * @param fontDir A system font directory, e.g. "/system/fonts"
+     * @param customization A OEM font customization
+     * @param updatableFontMap A map of updated font files
+     * @param lastModifiedDate A date that the system font is updated.
+     * @param configVersion A version of system font config.
+     * @param allowNonExistingFile true if allowing non-existing font files during parsing fonts.xml
+     * @return result of fonts.xml
+     *
+     * @throws XmlPullParserException
+     * @throws IOException
+     *
+     * @hide
+     */
+    public static FontConfig readFamilies(
             @NonNull XmlPullParser parser,
             @NonNull String fontDir,
             @NonNull FontCustomizationParser.Result customization,
@@ -159,7 +177,24 @@ public class FontListParser {
         }
 
         families.addAll(oemNamedFamilies.values());
-        return new FontConfig(families, aliases, lastModifiedDate, configVersion);
+
+        // Filters aliases that point to non-existing families.
+        Set<String> namedFamilies = new ArraySet<>();
+        for (int i = 0; i < families.size(); ++i) {
+            String name = families.get(i).getName();
+            if (name != null) {
+                namedFamilies.add(name);
+            }
+        }
+        List<FontConfig.Alias> filtered = new ArrayList<>();
+        for (int i = 0; i < aliases.size(); ++i) {
+            FontConfig.Alias alias = aliases.get(i);
+            if (namedFamilies.contains(alias.getOriginal())) {
+                filtered.add(alias);
+            }
+        }
+
+        return new FontConfig(families, filtered, lastModifiedDate, configVersion);
     }
 
     private static boolean keepReading(XmlPullParser parser)