Shard Javac

Test: m nothing
Test: allowlist frameworks/opt/calendar to bp2build convert
Test: add `javac_shard_size: 2` to calendar-common
Test: b //frameworks/opt/calendar:calendar-common
Bug: 297356812
Change-Id: Ie22bcf04946f3945952a74a46772b777b1522b70
diff --git a/bp2build/java_library_conversion_test.go b/bp2build/java_library_conversion_test.go
index c88af1b..5099b49 100644
--- a/bp2build/java_library_conversion_test.go
+++ b/bp2build/java_library_conversion_test.go
@@ -1109,3 +1109,23 @@
 		ctx.RegisterModuleType("java_import", java.ImportFactory)
 	})
 }
+
+func TestJavaLibrarySharding(t *testing.T) {
+	runJavaLibraryTestCase(t, Bp2buildTestCase{
+		Description: "java library with sharded compilation",
+		Blueprint: `java_library {
+			name: "lib1",
+			srcs: ["a.java"],
+			javac_shard_size: 3,
+			sdk_version: "current",
+		}`,
+		ExpectedBazelTargets: []string{
+			MakeBazelTarget("java_library", "lib1", AttrNameToString{
+				"srcs":             `["a.java"]`,
+				"sdk_version":      `"current"`,
+				"javac_shard_size": "3",
+			}),
+			MakeNeverlinkDuplicateTarget("java_library", "lib1"),
+		},
+	})
+}
diff --git a/java/java.go b/java/java.go
index 990a084..bc24050 100644
--- a/java/java.go
+++ b/java/java.go
@@ -2916,6 +2916,7 @@
 	Sdk_version             bazel.StringAttribute
 	Java_version            bazel.StringAttribute
 	Errorprone_force_enable bazel.BoolAttribute
+	Javac_shard_size        *int64
 }
 
 type javaDependencyLabels struct {
@@ -3101,6 +3102,7 @@
 		Java_version:            bazel.StringAttribute{Value: m.properties.Java_version},
 		Sdk_version:             bazel.StringAttribute{Value: m.deviceProperties.Sdk_version},
 		Errorprone_force_enable: errorproneForceEnable,
+		Javac_shard_size:        m.properties.Javac_shard_size,
 	}
 
 	for axis, configToProps := range archVariantProps {