1 files changed, 124 insertions, 0 deletions
diff --git a/src/main/java/com/google/devtools/build/lib/rules/objc/J2ObjcEntryClassProvider.java b/src/main/java/com/google/devtools/build/lib/rules/objc/J2ObjcEntryClassProvider.java
new file mode 100644
index 0000000000..6bbc6a505f
--- /dev/null
+++ b/src/main/java/com/google/devtools/build/lib/rules/objc/J2ObjcEntryClassProvider.java
@@ -0,0 +1,124 @@
+// Copyright 2014 The Bazel Authors. All rights reserved.
+//
+// Licensed under the Apache License, Version 2.0 (the "License");
+// you may not use this file except in compliance with the License.
+// You may obtain a copy of the License at
+//
+//    http://www.apache.org/licenses/LICENSE-2.0
+//
+// Unless required by applicable law or agreed to in writing, software
+// distributed under the License is distributed on an "AS IS" BASIS,
+// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+// See the License for the specific language governing permissions and
+// limitations under the License.
+
+package com.google.devtools.build.lib.rules.objc;
+
+import com.google.devtools.build.lib.analysis.RuleConfiguredTarget.Mode;
+import com.google.devtools.build.lib.analysis.RuleContext;
+import com.google.devtools.build.lib.analysis.TransitiveInfoProvider;
+import com.google.devtools.build.lib.collect.nestedset.NestedSet;
+import com.google.devtools.build.lib.collect.nestedset.NestedSetBuilder;
+import com.google.devtools.build.lib.concurrent.ThreadSafety.Immutable;
+import com.google.devtools.build.lib.packages.BuildType;
+
+/**
+ * This provider is exported by j2objc_library to export entry class information necessary for
+ * J2ObjC dead code removal performed at the binary level in ObjC rules.
+ */
+@Immutable
+public final class J2ObjcEntryClassProvider implements TransitiveInfoProvider {
+  private final NestedSet<String> entryClasses;
+
+  /**
+   * A builder for J2ObjcEntryClassProvider.
+   */
+  public static class Builder {
+    private final NestedSetBuilder<String> entryClassesBuilder = NestedSetBuilder.stableOrder();
+
+    /**
+     * Constructs a new, empty J2ObjcEntryClassProvider builder.
+     */
+    public Builder() {}
+
+    /**
+     * Transitively adds the given {@link J2ObjcEntryClassProvider}
+     * and all its properties to this builder.
+     *
+     * @param provider the J2ObjcEntryClassProvider to add
+     * @return this builder
+     */
+    public Builder addTransitive(J2ObjcEntryClassProvider provider) {
+      entryClassesBuilder.addTransitive(provider.getEntryClasses());
+      return this;
+    }
+
+    /**
+     * Transitively adds all the J2ObjcEntryClassProviders and all their properties
+     * that can be reached through the "deps" attribute.
+     *
+     * @param ruleContext the rule context
+     * @return this builder
+     */
+    public Builder addTransitive(RuleContext ruleContext) {
+      if (ruleContext.attributes().has("deps", BuildType.LABEL_LIST)) {
+        for (J2ObjcEntryClassProvider provider :
+            ruleContext.getPrerequisites("deps", Mode.TARGET, J2ObjcEntryClassProvider.class)) {
+          addTransitive(provider);
+        }
+      }
+
+      return this;
+    }
+
+    /**
+     * Adds the given entry classes to this builder. See {@link #getEntryClasses()}.
+     *
+     * @param entryClasses the entry classes to add
+     * @return this builder
+     */
+    public Builder addEntryClasses(Iterable<String> entryClasses) {
+      entryClassesBuilder.addAll(entryClasses);
+      return this;
+    }
+
+    /**
+     * Builds a J2ObjcEntryClassProvider from the information in this builder.
+     *
+     * @return the J2ObjcEntryClassProvider to be built
+     */
+    public J2ObjcEntryClassProvider build() {
+      return new J2ObjcEntryClassProvider(entryClassesBuilder.build());
+    }
+  }
+
+  /**
+   * Constructs a new J2ObjcEntryClassProvider that contains all the information
+   * that can be transitively reached through the "deps" attribute of the given rule context.
+   *
+   * @param ruleContext the rule context in which to look for deps
+   */
+  public static J2ObjcEntryClassProvider buildFrom(RuleContext ruleContext) {
+    return new Builder().addTransitive(ruleContext).build();
+  }
+
+  /**
+   * Constructs a {@link J2ObjcEntryClassProvider} to supply J2ObjC-translated ObjC sources to
+   * objc_binary for compilation and linking.
+   *
+   * @param entryClasses a set of names of Java classes to used as entry point for J2ObjC dead code
+   *     analysis. The Java class names should be in canonical format as defined by the Java
+   *     Language Specification.
+   */
+  private J2ObjcEntryClassProvider(NestedSet<String> entryClasses) {
+    this.entryClasses = entryClasses;
+  }
+
+  /**
+   * Returns a set of entry classes specified on attribute entry_classes of j2objc_library targets
+   * transitively.
+   */
+  public NestedSet<String> getEntryClasses() {
+    return entryClasses;
+  }
+}