--

MOS_MIGRATED_REVID=110484622

3 files changed, 240 insertions, 159 deletions

diff --git a/src/main/java/com/google/devtools/build/lib/rules/android/AndroidAaptActionHelper.java b/src/main/java/com/google/devtools/build/lib/rules/android/AndroidAaptActionHelper.java
index 7f02e310bf..4ce4cfcf9d 100644
--- a/src/main/java/com/google/devtools/build/lib/rules/android/AndroidAaptActionHelper.java
+++ b/src/main/java/com/google/devtools/build/lib/rules/android/AndroidAaptActionHelper.java
@@ -45,7 +45,7 @@ public final class AndroidAaptActionHelper {
   private final RuleContext ruleContext;
   private final Artifact manifest;
   private final Collection<Artifact> inputs = new LinkedHashSet<>();
-  private final List<ResourceContainer> resourceContainers;
+  private final Iterable<ResourceContainer> resourceContainers;
 
   /**
    * Constructs an instance of AndroidAaptActionHelper.
@@ -57,7 +57,7 @@ public final class AndroidAaptActionHelper {
    * @param resourceContainers The transitive closure of the ResourceContainers.
    */
   public AndroidAaptActionHelper(RuleContext ruleContext, Artifact manifest,
-      List<ResourceContainer> resourceContainers) {
+      Iterable<ResourceContainer> resourceContainers) {
     this.ruleContext = ruleContext;
     this.manifest = manifest;
     this.resourceContainers = resourceContainers;
@@ -277,7 +277,7 @@ public final class AndroidAaptActionHelper {
             ruleContext.getExecutablePrerequisite("$android_aapt_apk_generator", Mode.HOST))
         .setCommandLine(CommandLine.of(aaptCommand, false))
         .useParameterFile(ParameterFileType.UNQUOTED)
-        .setProgressMessage("Generating Proguard Configuration")
+        .setProgressMessage("Generating Proguard configuration for resources")
         .setMnemonic("AndroidAapt")
         .build(ruleContext));
   }
diff --git a/src/main/java/com/google/devtools/build/lib/rules/android/AndroidBinary.java b/src/main/java/com/google/devtools/build/lib/rules/android/AndroidBinary.java
index 638db7ed97..64b078d200 100644
--- a/src/main/java/com/google/devtools/build/lib/rules/android/AndroidBinary.java
+++ b/src/main/java/com/google/devtools/build/lib/rules/android/AndroidBinary.java
@@ -14,13 +14,12 @@
 package com.google.devtools.build.lib.rules.android;
 
 import static com.google.common.base.Strings.isNullOrEmpty;
+import static com.google.devtools.build.lib.rules.android.ProguardHelper.PROGUARD_SPECS;
 
-import com.google.common.base.Joiner;
 import com.google.common.base.Optional;
 import com.google.common.collect.ImmutableList;
 import com.google.common.collect.ImmutableMap;
 import com.google.common.collect.ImmutableSet;
-import com.google.common.collect.ImmutableSortedSet;
 import com.google.common.collect.Iterables;
 import com.google.common.collect.Multimap;
 import com.google.common.collect.MultimapBuilder;
@@ -38,7 +37,6 @@ import com.google.devtools.build.lib.analysis.RunfilesProvider;
 import com.google.devtools.build.lib.analysis.TransitiveInfoCollection;
 import com.google.devtools.build.lib.analysis.actions.CommandLine;
 import com.google.devtools.build.lib.analysis.actions.CustomCommandLine;
-import com.google.devtools.build.lib.analysis.actions.FileWriteAction;
 import com.google.devtools.build.lib.analysis.actions.SpawnAction;
 import com.google.devtools.build.lib.analysis.actions.SpawnAction.Builder;
 import com.google.devtools.build.lib.analysis.config.BuildConfiguration;
@@ -50,6 +48,7 @@ import com.google.devtools.build.lib.packages.BuildType;
 import com.google.devtools.build.lib.packages.TriState;
 import com.google.devtools.build.lib.rules.RuleConfiguredTargetFactory;
 import com.google.devtools.build.lib.rules.android.AndroidRuleClasses.MultidexMode;
+import com.google.devtools.build.lib.rules.android.ProguardHelper.ProguardOutput;
 import com.google.devtools.build.lib.rules.cpp.CcToolchainProvider;
 import com.google.devtools.build.lib.rules.cpp.CppHelper;
 import com.google.devtools.build.lib.rules.java.DeployArchiveBuilder;
@@ -60,7 +59,6 @@ import com.google.devtools.build.lib.rules.java.JavaConfiguration.JavaOptimizati
 import com.google.devtools.build.lib.rules.java.JavaSemantics;
 import com.google.devtools.build.lib.rules.java.JavaSourceInfoProvider;
 import com.google.devtools.build.lib.rules.java.JavaTargetAttributes;
-import com.google.devtools.build.lib.rules.java.ProguardSpecProvider;
 import com.google.devtools.build.lib.syntax.Type;
 import com.google.devtools.build.lib.util.Preconditions;
 import com.google.devtools.build.lib.vfs.PathFragment;
@@ -71,13 +69,10 @@ import java.util.List;
 import java.util.Map;
 import java.util.Set;
 
-import javax.annotation.Nullable;
-
 /**
  * An implementation for the "android_binary" rule.
  */
 public abstract class AndroidBinary implements RuleConfiguredTargetFactory {
-  static final String PROGUARD_SPECS = "proguard_specs";
 
   protected abstract JavaSemantics createJavaSemantics();
   protected abstract AndroidSemantics createAndroidSemantics();
@@ -211,7 +206,7 @@ public abstract class AndroidBinary implements RuleConfiguredTargetFactory {
           ruleContext.attributes().get("application_id", Type.STRING),
           getExpandedMakeVarsForAttr(ruleContext, "version_code"),
           getExpandedMakeVarsForAttr(ruleContext, "version_name"),
-          false, getProguardConfigArtifact(ruleContext, ""));
+          false, ProguardHelper.getProguardConfigArtifact(ruleContext, ""));
       if (ruleContext.hasErrors()) {
         return null;
       }
@@ -228,7 +223,7 @@ public abstract class AndroidBinary implements RuleConfiguredTargetFactory {
               ruleContext.attributes().get("application_id", Type.STRING),
               getExpandedMakeVarsForAttr(ruleContext, "version_code"),
               getExpandedMakeVarsForAttr(ruleContext, "version_name"),
-              true, getProguardConfigArtifact(ruleContext, "incremental"));
+              true, ProguardHelper.getProguardConfigArtifact(ruleContext, "incremental"));
       if (ruleContext.hasErrors()) {
         return null;
       }
@@ -245,7 +240,7 @@ public abstract class AndroidBinary implements RuleConfiguredTargetFactory {
               ruleContext.attributes().get("application_id", Type.STRING),
               getExpandedMakeVarsForAttr(ruleContext, "version_code"),
               getExpandedMakeVarsForAttr(ruleContext, "version_name"),
-              true, getProguardConfigArtifact(ruleContext, "incremental_split"));
+              true, ProguardHelper.getProguardConfigArtifact(ruleContext, "incremental_split"));
       if (ruleContext.hasErrors()) {
         return null;
       }
@@ -264,10 +259,10 @@ public abstract class AndroidBinary implements RuleConfiguredTargetFactory {
             ruleContext,
             resourceDeps,
             true,
-            getProguardConfigArtifact(ruleContext, ""));
+            ProguardHelper.getProguardConfigArtifact(ruleContext, ""));
       } else {
         resourceApk = applicationManifest.useCurrentResources(ruleContext,
-            getProguardConfigArtifact(ruleContext, ""));
+            ProguardHelper.getProguardConfigArtifact(ruleContext, ""));
       }
       incrementalResourceApk = applicationManifest
           .addStubApplication(ruleContext)
@@ -277,7 +272,7 @@ public abstract class AndroidBinary implements RuleConfiguredTargetFactory {
               ruleContext,
               resourceDeps,
               false,
-              getProguardConfigArtifact(ruleContext, "incremental"));
+              ProguardHelper.getProguardConfigArtifact(ruleContext, "incremental"));
       if (ruleContext.hasErrors()) {
         return null;
       }
@@ -288,7 +283,7 @@ public abstract class AndroidBinary implements RuleConfiguredTargetFactory {
             ruleContext,
             resourceDeps,
             false,
-            getProguardConfigArtifact(ruleContext, "incremental_split"));
+            ProguardHelper.getProguardConfigArtifact(ruleContext, "incremental_split"));
       if (ruleContext.hasErrors()) {
         return null;
       }
@@ -346,7 +341,8 @@ public abstract class AndroidBinary implements RuleConfiguredTargetFactory {
       JavaTargetAttributes resourceClasses,
       ImmutableList<Artifact> apksUnderTest,
       Artifact proguardMapping) throws InterruptedException {
-    ImmutableList<Artifact> proguardSpecs = getTransitiveProguardSpecs(ruleContext, resourceApk);
+    ImmutableList<Artifact> proguardSpecs = ProguardHelper.collectTransitiveProguardSpecs(
+        ruleContext, resourceApk.getResourceProguardConfig());
 
     ProguardOutput proguardOutput =
         applyProguard(
@@ -356,7 +352,7 @@ public abstract class AndroidBinary implements RuleConfiguredTargetFactory {
             filesBuilder,
             proguardSpecs,
             proguardMapping);
-    Artifact jarToDex = proguardOutput.outputJar;
+    Artifact jarToDex = proguardOutput.getOutputJar();
     DexingOutput dexingOutput =
         shouldDexWithJack(ruleContext)
             ? dexWithJack(ruleContext, androidCommon, proguardSpecs)
@@ -562,9 +558,9 @@ public abstract class AndroidBinary implements RuleConfiguredTargetFactory {
     androidSemantics.addTransitiveInfoProviders(
         builder, ruleContext, javaCommon, androidCommon, jarToDex);
 
-    if (proguardOutput.mapping != null) {
+    if (proguardOutput.getMapping() != null) {
       builder.add(ProguardMappingProvider.class,
-          new ProguardMappingProvider(proguardOutput.mapping));
+          new ProguardMappingProvider(proguardOutput.getMapping()));
     }
 
     return builder
@@ -730,70 +726,6 @@ public abstract class AndroidBinary implements RuleConfiguredTargetFactory {
     return context.expandMakeVariables(attr, value);
   }
 
-  @Immutable
-  private static final class ProguardOutput {
-    private final Artifact outputJar;
-    @Nullable private final Artifact mapping;
-
-    private ProguardOutput(Artifact outputJar, Artifact mapping) {
-      this.outputJar = outputJar;
-      this.mapping = mapping;
-    }
-  }
-
-  /**
-   * Retrieves the full set of proguard specs that should be applied to this binary.
-   *
-   * <p>If Proguard shouldn't be applied, or the legacy link mode is used and there are no
-   * proguard_specs on this rule, an empty list will be returned, regardless of any specs from
-   * dependencies or the resourceApk.
-   */
-  private static ImmutableList<Artifact> getTransitiveProguardSpecs(
-      RuleContext ruleContext, ResourceApk resourceApk) {
-    JavaOptimizationMode optMode = getJavaOptimizationMode(ruleContext);
-    if (optMode == JavaOptimizationMode.NOOP) {
-      return ImmutableList.of();
-    }
-
-    ImmutableList<Artifact> proguardSpecs =
-        ruleContext.getPrerequisiteArtifacts(PROGUARD_SPECS, Mode.TARGET).list();
-    if (optMode == JavaOptimizationMode.LEGACY && proguardSpecs.isEmpty()) {
-      return ImmutableList.of();
-    }
-
-    // TODO(kmb): In modes other than LEGACY verify that proguard specs don't include -dont... flags
-    // since those flags would override the desired optMode (b/25621573)
-    ImmutableSortedSet.Builder<Artifact> builder =
-        ImmutableSortedSet.orderedBy(Artifact.EXEC_PATH_COMPARATOR)
-            .addAll(proguardSpecs)
-            .addAll(ruleContext
-                .getPrerequisiteArtifacts(":extra_proguard_specs", Mode.TARGET)
-                .list());
-    for (ProguardSpecProvider dep :
-        ruleContext.getPrerequisites("deps", Mode.TARGET, ProguardSpecProvider.class)) {
-      builder.addAll(dep.getTransitiveProguardSpecs());
-    }
-
-    // Include proguard spec generated from rule's resources
-    Artifact output = resourceApk.getResourceProguardConfig();
-    builder.add(output);
-
-    // Generate and include implicit Proguard spec for requested mode.
-    if (!optMode.getImplicitProguardDirectives().isEmpty()) {
-      Artifact implicitDirectives =
-          getProguardConfigArtifact(ruleContext, optMode.name().toLowerCase());
-      ruleContext.registerAction(
-          new FileWriteAction(
-              ruleContext.getActionOwner(),
-              implicitDirectives,
-              optMode.getImplicitProguardDirectives(),
-              /*executable*/ false));
-      builder.add(implicitDirectives);
-    }
-
-    return builder.build().asList();
-  }
-
   private static JavaOptimizationMode getJavaOptimizationMode(RuleContext ruleContext) {
     return ruleContext.getConfiguration().getFragment(JavaConfiguration.class)
         .getJavaOptimizationMode();
@@ -821,8 +753,13 @@ public abstract class AndroidBinary implements RuleConfiguredTargetFactory {
     }
 
     AndroidSdkProvider sdk = AndroidSdkProvider.fromRuleContext(ruleContext);
-    return createProguardAction(ruleContext, common, sdk.getProguard(), deployJarArtifact,
-        proguardSpecs, proguardMapping, sdk.getAndroidJar(), proguardOutputJar, filesBuilder);
+    NestedSet<Artifact> libraryJars = NestedSetBuilder.<Artifact>naiveLinkOrder()
+        .add(sdk.getAndroidJar())
+        .addTransitive(common.getTransitiveNeverLinkLibraries())
+        .build();
+    return ProguardHelper.createProguardAction(ruleContext, sdk.getProguard(), deployJarArtifact,
+        proguardSpecs, proguardMapping, libraryJars, proguardOutputJar,
+        ruleContext.attributes().get("proguard_generate_mapping", Type.BOOLEAN), filesBuilder);
   }
 
   private static ProguardOutput createEmptyProguardAction(RuleContext ruleContext,
@@ -845,66 +782,6 @@ public abstract class AndroidBinary implements RuleConfiguredTargetFactory {
     return new ProguardOutput(deployJarArtifact, null);
   }
 
-  private static ProguardOutput createProguardAction(RuleContext ruleContext, AndroidCommon common,
-      FilesToRunProvider proguard,
-      Artifact jar, ImmutableList<Artifact> proguardSpecs,
-      Artifact proguardMapping, Artifact androidJar, Artifact proguardOutputJar,
-      NestedSetBuilder<Artifact> filesBuilder) throws InterruptedException {
-    Iterable<Artifact> libraryJars = NestedSetBuilder.<Artifact>naiveLinkOrder()
-        .add(androidJar)
-        .addTransitive(common.getTransitiveNeverLinkLibraries())
-        .build();
-
-    Builder builder = new SpawnAction.Builder()
-        .addInput(jar)
-        .addInputs(libraryJars)
-        .addInputs(proguardSpecs)
-        .addOutput(proguardOutputJar)
-        .setExecutable(proguard)
-        .setProgressMessage("Trimming binary with proguard")
-        .setMnemonic("Proguard")
-        .addArgument("-injars")
-        .addArgument(jar.getExecPathString());
-
-    for (Artifact libraryJar : libraryJars) {
-      builder.addArgument("-libraryjars")
-          .addArgument(libraryJar.getExecPathString());
-    }
-
-    filesBuilder.add(proguardOutputJar);
-
-    if (proguardMapping != null) {
-      builder.addInput(proguardMapping)
-          .addArgument("-applymapping")
-          .addArgument(proguardMapping.getExecPathString());
-    }
-
-    builder.addArgument("-outjars")
-        .addArgument(proguardOutputJar.getExecPathString());
-
-    for (Artifact proguardSpec : proguardSpecs) {
-      builder.addArgument("@" + proguardSpec.getExecPathString());
-    }
-
-    Artifact proguardOutputMap = null;
-    JavaOptimizationMode optMode = getJavaOptimizationMode(ruleContext);
-    if (ruleContext.attributes().get("proguard_generate_mapping", Type.BOOLEAN)
-        || optMode.alwaysGenerateOutputMapping()) {
-      // TODO(kmb): Verify that proguard spec files don't contain -printmapping directions which
-      // this -printmapping command line flag will override.
-      proguardOutputMap = ruleContext.getImplicitOutputArtifact(
-          AndroidRuleClasses.ANDROID_BINARY_PROGUARD_MAP);
-
-      builder.addOutput(proguardOutputMap)
-          .addArgument("-printmapping")
-          .addArgument(proguardOutputMap.getExecPathString());
-      filesBuilder.add(proguardOutputMap);
-    }
-
-    ruleContext.registerAction(builder.build(ruleContext));
-    return new ProguardOutput(proguardOutputJar, proguardOutputMap);
-  }
-
   @Immutable
   private static final class DexingOutput {
     private final Artifact classesDexZip;
@@ -1419,16 +1296,4 @@ public abstract class AndroidBinary implements RuleConfiguredTargetFactory {
     return ruleContext.getUniqueDirectoryArtifact("_dx", baseName,
         ruleContext.getBinOrGenfilesDirectory());
   }
-
-  /**
-   * Returns an intermediate artifact used to run Proguard.
-   */
-  public static Artifact getProguardConfigArtifact(RuleContext ruleContext, String prefix) {
-    // TODO(bazel-team): Remove the redundant inclusion of the rule name, as getUniqueDirectory
-    // includes the rulename as well.
-    return Preconditions.checkNotNull(ruleContext.getUniqueDirectoryArtifact(
-        "proguard",
-        Joiner.on("_").join(prefix, ruleContext.getLabel().getName(), "proguard.cfg"),
-        ruleContext.getBinOrGenfilesDirectory()));
-  }
 }
diff --git a/src/main/java/com/google/devtools/build/lib/rules/android/ProguardHelper.java b/src/main/java/com/google/devtools/build/lib/rules/android/ProguardHelper.java
new file mode 100644
index 0000000000..f752e182a5
--- /dev/null
+++ b/src/main/java/com/google/devtools/build/lib/rules/android/ProguardHelper.java
@@ -0,0 +1,216 @@
+// Copyright 2015 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.android;
+
+import com.google.common.base.Joiner;
+import com.google.common.base.Preconditions;
+import com.google.common.collect.ImmutableList;
+import com.google.common.collect.ImmutableSortedSet;
+import com.google.devtools.build.lib.actions.Artifact;
+import com.google.devtools.build.lib.analysis.FilesToRunProvider;
+import com.google.devtools.build.lib.analysis.RuleConfiguredTarget.Mode;
+import com.google.devtools.build.lib.analysis.RuleContext;
+import com.google.devtools.build.lib.analysis.actions.FileWriteAction;
+import com.google.devtools.build.lib.analysis.actions.SpawnAction;
+import com.google.devtools.build.lib.analysis.actions.SpawnAction.Builder;
+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;
+import com.google.devtools.build.lib.rules.java.JavaConfiguration;
+import com.google.devtools.build.lib.rules.java.JavaConfiguration.JavaOptimizationMode;
+import com.google.devtools.build.lib.rules.java.ProguardSpecProvider;
+
+import javax.annotation.Nullable;
+
+/**
+ * Common code for proguarding Android binaries.
+ */
+public class ProguardHelper {
+
+  static final String PROGUARD_SPECS = "proguard_specs";
+
+  @Immutable
+  static final class ProguardOutput {
+    private final Artifact outputJar;
+    @Nullable private final Artifact mapping;
+
+    ProguardOutput(Artifact outputJar, @Nullable Artifact mapping) {
+      this.outputJar = outputJar;
+      this.mapping = mapping;
+    }
+
+    public Artifact getOutputJar() {
+      return outputJar;
+    }
+
+    @Nullable
+    public Artifact getMapping() {
+      return mapping;
+    }
+
+  }
+
+  private ProguardHelper() {}
+
+  /**
+   * Retrieves the full set of proguard specs that should be applied to this binary, including the
+   * specs passed in, if Proguard should run on the given rule.  {@link #createProguardAction}
+   * relies on this method returning an empty list if the given rule doesn't declare specs in
+   * --java_optimization_mode=legacy.
+   *
+   * <p>If Proguard shouldn't be applied, or the legacy link mode is used and there are no
+   * proguard_specs on this rule, an empty list will be returned, regardless of any given specs or
+   * specs from dependencies.  {@link AndroidBinary#createAndroidBinary} relies on that behavior.
+   */
+  public static ImmutableList<Artifact> collectTransitiveProguardSpecs(RuleContext ruleContext,
+      Artifact... specsToInclude) {
+    JavaOptimizationMode optMode = getJavaOptimizationMode(ruleContext);
+    if (optMode == JavaOptimizationMode.NOOP) {
+      return ImmutableList.of();
+    }
+
+    ImmutableList<Artifact> proguardSpecs =
+        ruleContext.attributes().has(PROGUARD_SPECS, BuildType.LABEL_LIST)
+            ? ruleContext.getPrerequisiteArtifacts(PROGUARD_SPECS, Mode.TARGET).list()
+            : ImmutableList.<Artifact>of();
+    if (optMode == JavaOptimizationMode.LEGACY && proguardSpecs.isEmpty()) {
+      return ImmutableList.of();
+    }
+
+    // TODO(bazel-team): In modes except LEGACY verify that proguard specs don't include -dont...
+    // flags since those flags would override the desired optMode
+    ImmutableSortedSet.Builder<Artifact> builder =
+        ImmutableSortedSet.orderedBy(Artifact.EXEC_PATH_COMPARATOR)
+            .addAll(proguardSpecs)
+            .add(specsToInclude)
+            .addAll(ruleContext
+                .getPrerequisiteArtifacts(":extra_proguard_specs", Mode.TARGET)
+                .list());
+    for (ProguardSpecProvider dep :
+        ruleContext.getPrerequisites("deps", Mode.TARGET, ProguardSpecProvider.class)) {
+      builder.addAll(dep.getTransitiveProguardSpecs());
+    }
+
+    // Generate and include implicit Proguard spec for requested mode.
+    if (!optMode.getImplicitProguardDirectives().isEmpty()) {
+      Artifact implicitDirectives =
+          getProguardConfigArtifact(ruleContext, optMode.name().toLowerCase());
+      ruleContext.registerAction(
+          new FileWriteAction(
+              ruleContext.getActionOwner(),
+              implicitDirectives,
+              optMode.getImplicitProguardDirectives(),
+              /*executable*/ false));
+      builder.add(implicitDirectives);
+    }
+
+    return builder.build().asList();
+  }
+
+  /**
+   * Creates an action to run Proguard over the given {@code programJar} with various other given
+   * inputs to produce {@code proguardOutputJar}.  If requested explicitly, or implicitly with
+   * --java_optimization_mode, the action also produces a mapping file (which shows what methods and
+   * classes in the output Jar correspond to which methods and classes in the input).  The "pair"
+   * returned by this method indicates whether a mapping is being produced.
+   *
+   * <p>See the Proguard manual for the meaning of the various artifacts in play.
+   *
+   * @param proguard Proguard executable to use
+   * @param proguardSpecs Proguard specification files to pass to Proguard
+   * @param proguardMapping optional mapping file for Proguard to apply
+   * @param libraryJars any other Jar files that the {@code programJar} will run against
+   * @param mappingRequested whether to ask Proguard to output a mapping file (a mapping will be
+   *        produced anyway if --java_optimization_mode includes obfuscation)
+   * @param filesBuilder all artifacts produced by this rule will be added to this builder
+   */
+  public static ProguardOutput createProguardAction(RuleContext ruleContext,
+      FilesToRunProvider proguard,
+      Artifact programJar,
+      ImmutableList<Artifact> proguardSpecs,
+      @Nullable Artifact proguardMapping,
+      NestedSet<Artifact> libraryJars,
+      Artifact proguardOutputJar,
+      boolean mappingRequested,
+      NestedSetBuilder<Artifact> filesBuilder) throws InterruptedException {
+    JavaOptimizationMode optMode = getJavaOptimizationMode(ruleContext);
+    Preconditions.checkArgument(optMode != JavaOptimizationMode.NOOP);
+    Preconditions.checkArgument(optMode != JavaOptimizationMode.LEGACY || !proguardSpecs.isEmpty());
+
+    Builder builder = new SpawnAction.Builder()
+        .addInput(programJar)
+        .addInputs(libraryJars)
+        .addInputs(proguardSpecs)
+        .addOutput(proguardOutputJar)
+        .setExecutable(proguard)
+        .setProgressMessage("Trimming binary with Proguard")
+        .setMnemonic("Proguard")
+        .addArgument("-injars")
+        .addArgument(programJar.getExecPathString());
+
+    for (Artifact libraryJar : libraryJars) {
+      builder.addArgument("-libraryjars")
+          .addArgument(libraryJar.getExecPathString());
+    }
+
+    filesBuilder.add(proguardOutputJar);
+
+    if (proguardMapping != null) {
+      builder.addInput(proguardMapping)
+          .addArgument("-applymapping")
+          .addArgument(proguardMapping.getExecPathString());
+    }
+
+    builder.addArgument("-outjars")
+        .addArgument(proguardOutputJar.getExecPathString());
+
+    for (Artifact proguardSpec : proguardSpecs) {
+      builder.addArgument("@" + proguardSpec.getExecPathString());
+    }
+
+    Artifact proguardOutputMap = null;
+    if (mappingRequested || optMode.alwaysGenerateOutputMapping()) {
+      // TODO(bazel-team): Verify that proguard spec files don't contain -printmapping directions
+      // which this -printmapping command line flag will override.
+      proguardOutputMap = ruleContext.getImplicitOutputArtifact(
+          AndroidRuleClasses.ANDROID_BINARY_PROGUARD_MAP);
+
+      builder.addOutput(proguardOutputMap)
+          .addArgument("-printmapping")
+          .addArgument(proguardOutputMap.getExecPathString());
+      filesBuilder.add(proguardOutputMap);
+    }
+
+    ruleContext.registerAction(builder.build(ruleContext));
+    return new ProguardOutput(proguardOutputJar, proguardOutputMap);
+  }
+
+  /**
+   * Returns an intermediate artifact used to run Proguard.
+   */
+  public static Artifact getProguardConfigArtifact(RuleContext ruleContext, String prefix) {
+    // TODO(bazel-team): Remove the redundant inclusion of the rule name, as getUniqueDirectory
+    // includes the rulename as well.
+    return Preconditions.checkNotNull(ruleContext.getUniqueDirectoryArtifact(
+        "proguard",
+        Joiner.on("_").join(prefix, ruleContext.getLabel().getName(), "proguard.cfg"),
+        ruleContext.getBinOrGenfilesDirectory()));
+  }
+
+  private static JavaOptimizationMode getJavaOptimizationMode(RuleContext ruleContext) {
+    return ruleContext.getConfiguration().getFragment(JavaConfiguration.class)
+        .getJavaOptimizationMode();
+  }
+}