Add FontFamily.Builder instead of constructor

Bug: 181124737
Test: atest FontFamilyUpdateRequestTest
Change-Id: I6fd9b7cb40e6f4d168f95953cb488b2c43d6abef

2 files changed, 46 insertions, 7 deletions

diff --git a/core/api/system-current.txt b/core/api/system-current.txt
index 5ca4d35d4c22..6f7a4d061248 100644
--- a/core/api/system-current.txt
+++ b/core/api/system-current.txt
@@ -2881,11 +2881,16 @@ package android.graphics.fonts {
   }
 
   public static final class FontFamilyUpdateRequest.FontFamily {
-    ctor public FontFamilyUpdateRequest.FontFamily(@NonNull String, @NonNull java.util.List<android.graphics.fonts.FontFamilyUpdateRequest.Font>);
     method @NonNull public java.util.List<android.graphics.fonts.FontFamilyUpdateRequest.Font> getFonts();
     method @NonNull public String getName();
   }
 
+  public static final class FontFamilyUpdateRequest.FontFamily.Builder {
+    ctor public FontFamilyUpdateRequest.FontFamily.Builder(@NonNull String, @NonNull java.util.List<android.graphics.fonts.FontFamilyUpdateRequest.Font>);
+    method @NonNull public android.graphics.fonts.FontFamilyUpdateRequest.FontFamily.Builder addFont(@NonNull android.graphics.fonts.FontFamilyUpdateRequest.Font);
+    method @NonNull public android.graphics.fonts.FontFamilyUpdateRequest.FontFamily build();
+  }
+
   public final class FontFileUpdateRequest {
     ctor public FontFileUpdateRequest(@NonNull android.os.ParcelFileDescriptor, @NonNull byte[]);
     method @NonNull public android.os.ParcelFileDescriptor getParcelFileDescriptor();
diff --git a/core/java/android/graphics/fonts/FontFamilyUpdateRequest.java b/core/java/android/graphics/fonts/FontFamilyUpdateRequest.java
index 25758e9d9a61..8c7695ad5a5a 100644
--- a/core/java/android/graphics/fonts/FontFamilyUpdateRequest.java
+++ b/core/java/android/graphics/fonts/FontFamilyUpdateRequest.java
@@ -72,6 +72,45 @@ public final class FontFamilyUpdateRequest {
      * A font family definition.
      */
     public static final class FontFamily {
+
+        /**
+         * Builds a {@link FontFamily}.
+         */
+        public static final class Builder {
+            @NonNull private final String mName;
+            @NonNull private final List<Font> mFonts;
+
+            /**
+             * Constructs a {@link FontFamily.Builder}.
+             */
+            public Builder(@NonNull String name, @NonNull List<Font> fonts) {
+                Objects.requireNonNull(name);
+                Preconditions.checkStringNotEmpty(name);
+                Objects.requireNonNull(fonts);
+                Preconditions.checkCollectionElementsNotNull(fonts, "fonts");
+                Preconditions.checkCollectionNotEmpty(fonts, "fonts");
+                mName = name;
+                mFonts = new ArrayList<>(fonts);
+            }
+
+            /**
+             * Adds a {@link Font} to the builder.
+             *
+             * @return This builder object.
+             */
+            public @NonNull Builder addFont(@NonNull Font font) {
+                mFonts.add(font);
+                return this;
+            }
+
+            /**
+             * Builds a {@link FontFamily}.
+             */
+            public @NonNull FontFamily build() {
+                return new FontFamily(mName, mFonts);
+            }
+        }
+
         @NonNull
         private final String mName;
         @NonNull
@@ -90,12 +129,7 @@ public final class FontFamilyUpdateRequest {
          * @see android.graphics.Typeface#create(String, int)
          * @see Font
          */
-        public FontFamily(@NonNull String name, @NonNull List<Font> fonts) {
-            Objects.requireNonNull(name);
-            Preconditions.checkStringNotEmpty(name);
-            Objects.requireNonNull(fonts);
-            Preconditions.checkCollectionElementsNotNull(fonts, "fonts");
-            Preconditions.checkCollectionNotEmpty(fonts, "fonts");
+        private FontFamily(@NonNull String name, @NonNull List<Font> fonts) {
             mName = name;
             mFonts = fonts;
         }