Don't write empty Main-Class manifest entries

When java_binary.create_executable=0, omit the Main-Class entry in the deploy
jar's manifest instead of writing an empty main class name.

--
MOS_MIGRATED_REVID=120443936

1 files changed, 11 insertions, 16 deletions

diff --git a/src/main/java/com/google/devtools/build/lib/bazel/rules/java/BazelJavaSemantics.java b/src/main/java/com/google/devtools/build/lib/bazel/rules/java/BazelJavaSemantics.java
index 4e8513a1e1..980691f957 100644
--- a/src/main/java/com/google/devtools/build/lib/bazel/rules/java/BazelJavaSemantics.java
+++ b/src/main/java/com/google/devtools/build/lib/bazel/rules/java/BazelJavaSemantics.java
@@ -80,24 +80,19 @@ public class BazelJavaSemantics implements JavaSemantics {
   @Override
   public void checkRule(RuleContext ruleContext, JavaCommon javaCommon) {
   }
-  
+
   private String getMainClassInternal(RuleContext ruleContext, ImmutableList<Artifact> sources) {
-    String mainClass = ruleContext.getRule().isAttrDefined("main_class", Type.STRING)
-        ? ruleContext.attributes().get("main_class", Type.STRING) : "";
-    boolean createExecutable = ruleContext.attributes().get("create_executable", Type.BOOLEAN);
-    boolean useTestrunner = ruleContext.attributes().get("use_testrunner", Type.BOOLEAN)
-        && !useLegacyJavaTest(ruleContext);
-
-    if (createExecutable) {
-      if (useTestrunner) {
-        mainClass = "com.google.testing.junit.runner.BazelTestRunner";
-      } else { /* java_binary or non-Junit java_test */
-        if (mainClass.isEmpty()) {
-          mainClass = JavaCommon.determinePrimaryClass(ruleContext, sources);
-        }
-      }
+    if (!ruleContext.attributes().get("create_executable", Type.BOOLEAN)) {
+      return null;
+    }
+    if (ruleContext.attributes().get("use_testrunner", Type.BOOLEAN)
+        && !useLegacyJavaTest(ruleContext)) {
+      return "com.google.testing.junit.runner.BazelTestRunner";
+    }
+    String mainClass = ruleContext.attributes().get("main_class", Type.STRING);
+    if (mainClass.isEmpty()) {
+      mainClass = JavaCommon.determinePrimaryClass(ruleContext, sources);
     }
-
     return mainClass;
   }