Merge outputs in java_common.merge.

RELNOTES: [JavaInfo] Outputs are merged in java_common.merge().
PiperOrigin-RevId: 203474741

2 files changed, 14 insertions, 3 deletions

diff --git a/src/main/java/com/google/devtools/build/lib/rules/java/JavaInfo.java b/src/main/java/com/google/devtools/build/lib/rules/java/JavaInfo.java
index e6aa29093e..ab6d409b1f 100644
--- a/src/main/java/com/google/devtools/build/lib/rules/java/JavaInfo.java
+++ b/src/main/java/com/google/devtools/build/lib/rules/java/JavaInfo.java
@@ -128,6 +128,8 @@ public final class JavaInfo extends NativeInfo implements JavaInfoApi<Artifact>
         JavaInfo.fetchProvidersFromList(providers, JavaPluginInfoProvider.class);
     List<JavaExportsProvider> javaExportsProviders =
         JavaInfo.fetchProvidersFromList(providers, JavaExportsProvider.class);
+    List<JavaRuleOutputJarsProvider> javaRuleOutputJarsProviders =
+        JavaInfo.fetchProvidersFromList(providers, JavaRuleOutputJarsProvider.class);
 
 
     Runfiles mergedRunfiles = Runfiles.EMPTY;
@@ -145,9 +147,8 @@ public final class JavaInfo extends NativeInfo implements JavaInfoApi<Artifact>
             JavaStrictCompilationArgsProvider.merge(javaStrictCompilationArgsProviders))
         .addProvider(
             JavaSourceJarsProvider.class, JavaSourceJarsProvider.merge(javaSourceJarsProviders))
-        // When a rule merges multiple JavaProviders, its purpose is to pass on information, so
-        // it doesn't have any output jars.
-        .addProvider(JavaRuleOutputJarsProvider.class, JavaRuleOutputJarsProvider.builder().build())
+        .addProvider(JavaRuleOutputJarsProvider.class,
+            JavaRuleOutputJarsProvider.merge(javaRuleOutputJarsProviders))
         .addProvider(JavaRunfilesProvider.class, new JavaRunfilesProvider(mergedRunfiles))
         .addProvider(
             JavaPluginInfoProvider.class, JavaPluginInfoProvider.merge(javaPluginInfoProviders))
diff --git a/src/main/java/com/google/devtools/build/lib/rules/java/JavaRuleOutputJarsProvider.java b/src/main/java/com/google/devtools/build/lib/rules/java/JavaRuleOutputJarsProvider.java
index 5595651c83..d7aa8ea514 100644
--- a/src/main/java/com/google/devtools/build/lib/rules/java/JavaRuleOutputJarsProvider.java
+++ b/src/main/java/com/google/devtools/build/lib/rules/java/JavaRuleOutputJarsProvider.java
@@ -27,6 +27,7 @@ import com.google.devtools.build.lib.skyframe.serialization.autocodec.AutoCodec;
 import com.google.devtools.build.lib.skylarkbuildapi.java.JavaRuleOutputJarsProviderApi;
 import com.google.devtools.build.lib.skylarkbuildapi.java.OutputJarApi;
 import com.google.devtools.build.lib.syntax.SkylarkList;
+import java.util.Collection;
 import java.util.stream.Collectors;
 import javax.annotation.Nullable;
 
@@ -150,6 +151,15 @@ public final class JavaRuleOutputJarsProvider
     return new Builder();
   }
 
+  public static JavaRuleOutputJarsProvider merge(
+      Collection<JavaRuleOutputJarsProvider> providers) {
+    Builder builder = new Builder();
+    for (JavaRuleOutputJarsProvider provider : providers) {
+      builder.addOutputJars(provider.getOutputJars());
+    }
+    return builder.build();
+  }
+
   /**
    * Builder for {@link JavaRuleOutputJarsProvider}.
    */