Read the .jdeps files created from Java header compilations when finishing the action. The benefit is that reading these files is distributed more evenly across the build. A single Javac compile at the end cannot be bottlenecked upon needing to read hundreds of these files. RELNOTES: None. PiperOrigin-RevId: 253010039

diff --git a/src/main/java/com/google/devtools/build/lib/analysis/actions/SpawnAction.java b/src/main/java/com/google/devtools/build/lib/analysis/actions/SpawnAction.java
index fcc15da..a8c6f70 100644
--- a/src/main/java/com/google/devtools/build/lib/analysis/actions/SpawnAction.java
+++ b/src/main/java/com/google/devtools/build/lib/analysis/actions/SpawnAction.java

@@ -56,6 +56,7 @@
 import com.google.devtools.build.lib.actions.SingleStringArgFormatter;
 import com.google.devtools.build.lib.actions.Spawn;
 import com.google.devtools.build.lib.actions.SpawnContinuation;
+import com.google.devtools.build.lib.actions.SpawnResult;
 import com.google.devtools.build.lib.actions.extra.EnvironmentVariable;
 import com.google.devtools.build.lib.actions.extra.ExtraActionInfo;
 import com.google.devtools.build.lib.actions.extra.SpawnInfo;
@@ -71,6 +72,7 @@
 import com.google.devtools.build.lib.syntax.SkylarkList;
 import com.google.devtools.build.lib.util.Fingerprint;
 import com.google.devtools.build.lib.util.LazyString;
+import com.google.devtools.build.lib.util.Pair;
 import com.google.devtools.build.lib.util.ShellEscaper;
 import com.google.devtools.build.lib.vfs.PathFragment;
 import com.google.errorprone.annotations.CompileTimeConstant;
@@ -81,6 +83,7 @@
 import java.util.LinkedHashMap;
 import java.util.List;
 import java.util.Map;
+import java.util.function.Consumer;
 import javax.annotation.CheckReturnValue;
 import javax.annotation.Nullable;
 
@@ -108,6 +111,7 @@
 
   private final ExtraActionInfoSupplier extraActionInfoSupplier;
   private final Artifact primaryOutput;
+  private final Consumer<Pair<ActionExecutionContext, List<SpawnResult>>> resultConsumer;
 
   /**
    * Constructs a SpawnAction using direct initialization arguments.
@@ -160,6 +164,7 @@
         EmptyRunfilesSupplier.INSTANCE,
         mnemonic,
         false,
+        null,
         null);
   }
 
@@ -203,7 +208,8 @@
       RunfilesSupplier runfilesSupplier,
       String mnemonic,
       boolean executeUnconditionally,
-      ExtraActionInfoSupplier extraActionInfoSupplier) {
+      ExtraActionInfoSupplier extraActionInfoSupplier,
+      Consumer<Pair<ActionExecutionContext, List<SpawnResult>>> resultConsumer) {
     super(owner, tools, inputs, runfilesSupplier, outputs, env);
     this.primaryOutput = primaryOutput;
     this.resourceSet = resourceSet;
@@ -215,6 +221,7 @@
     this.mnemonic = mnemonic;
     this.executeUnconditionally = executeUnconditionally;
     this.extraActionInfoSupplier = extraActionInfoSupplier;
+    this.resultConsumer = resultConsumer;
   }
 
   @Override
@@ -589,6 +596,8 @@
     protected ExtraActionInfoSupplier extraActionInfoSupplier = null;
     private boolean disableSandboxing = false;
 
+    private Consumer<Pair<ActionExecutionContext, List<SpawnResult>>> resultConsumer = null;
+
     /**
      * Creates a SpawnAction builder.
      */
@@ -752,7 +761,8 @@
           runfilesSupplier,
           mnemonic,
           executeUnconditionally,
-          extraActionInfoSupplier);
+          extraActionInfoSupplier,
+          resultConsumer);
     }
 
     /**
@@ -1255,6 +1265,12 @@
       this.disableSandboxing = true;
       return this;
     }
+
+    public Builder addResultConsumer(
+        Consumer<Pair<ActionExecutionContext, List<SpawnResult>>> resultConsumer) {
+      this.resultConsumer = resultConsumer;
+      return this;
+    }
   }
 
   /**
@@ -1327,6 +1343,9 @@
       try {
         SpawnContinuation nextContinuation = spawnContinuation.execute();
         if (nextContinuation.isDone()) {
+          if (resultConsumer != null) {
+            resultConsumer.accept(Pair.of(actionExecutionContext, nextContinuation.get()));
+          }
           afterExecute(actionExecutionContext);
           return ActionContinuationOrResult.of(ActionResult.create(nextContinuation.get()));
         }

diff --git a/src/main/java/com/google/devtools/build/lib/analysis/actions/StarlarkAction.java b/src/main/java/com/google/devtools/build/lib/analysis/actions/StarlarkAction.java
index 83a9971..00173c0 100644
--- a/src/main/java/com/google/devtools/build/lib/analysis/actions/StarlarkAction.java
+++ b/src/main/java/com/google/devtools/build/lib/analysis/actions/StarlarkAction.java

@@ -98,7 +98,8 @@
         runfilesSupplier,
         mnemonic,
         /* executeUnconditionally */ false,
-        /* extraActionInfoSupplier */ null);
+        /* extraActionInfoSupplier */ null,
+        /* resultConsumer */ null);
     this.allInputs = inputs;
     this.unusedInputsList = unusedInputsList;
   }

diff --git a/src/main/java/com/google/devtools/build/lib/analysis/extra/ExtraAction.java b/src/main/java/com/google/devtools/build/lib/analysis/extra/ExtraAction.java
index 4762ba7..c4cfef3 100644
--- a/src/main/java/com/google/devtools/build/lib/analysis/extra/ExtraAction.java
+++ b/src/main/java/com/google/devtools/build/lib/analysis/extra/ExtraAction.java

@@ -91,6 +91,7 @@
         CompositeRunfilesSupplier.of(shadowedAction.getRunfilesSupplier(), runfilesSupplier),
         mnemonic,
         false,
+        null,
         null);
     this.shadowedAction = shadowedAction;
     this.createDummyOutput = createDummyOutput;

diff --git a/src/main/java/com/google/devtools/build/lib/rules/cpp/LtoBackendAction.java b/src/main/java/com/google/devtools/build/lib/rules/cpp/LtoBackendAction.java
index 05b9146..c4fc42d 100644
--- a/src/main/java/com/google/devtools/build/lib/rules/cpp/LtoBackendAction.java
+++ b/src/main/java/com/google/devtools/build/lib/rules/cpp/LtoBackendAction.java

@@ -94,6 +94,7 @@
         runfilesSupplier,
         mnemonic,
         false,
+        null,
         null);
     mandatoryInputs = inputs;
     Preconditions.checkState(

diff --git a/src/main/java/com/google/devtools/build/lib/rules/genrule/GenRuleAction.java b/src/main/java/com/google/devtools/build/lib/rules/genrule/GenRuleAction.java
index ed9a977..6e69d32 100644
--- a/src/main/java/com/google/devtools/build/lib/rules/genrule/GenRuleAction.java
+++ b/src/main/java/com/google/devtools/build/lib/rules/genrule/GenRuleAction.java

@@ -64,6 +64,7 @@
         runfilesSupplier,
         MNEMONIC,
         false,
+        null,
         null);
   }
 

diff --git a/src/main/java/com/google/devtools/build/lib/rules/java/JavaHeaderCompileActionBuilder.java b/src/main/java/com/google/devtools/build/lib/rules/java/JavaHeaderCompileActionBuilder.java
index 606158e..edf4b96 100644
--- a/src/main/java/com/google/devtools/build/lib/rules/java/JavaHeaderCompileActionBuilder.java
+++ b/src/main/java/com/google/devtools/build/lib/rules/java/JavaHeaderCompileActionBuilder.java

@@ -21,10 +21,15 @@
 import static java.util.stream.Collectors.joining;
 
 import com.google.common.collect.ImmutableList;
+import com.google.common.collect.ImmutableMap;
 import com.google.common.collect.ImmutableSet;
+import com.google.common.collect.Iterables;
+import com.google.devtools.build.lib.actions.ActionExecutionContext;
 import com.google.devtools.build.lib.actions.Artifact;
+import com.google.devtools.build.lib.actions.ExecutionRequirements;
 import com.google.devtools.build.lib.actions.ParamFileInfo;
 import com.google.devtools.build.lib.actions.ParameterFile.ParameterFileType;
+import com.google.devtools.build.lib.actions.SpawnResult;
 import com.google.devtools.build.lib.analysis.FilesToRunProvider;
 import com.google.devtools.build.lib.analysis.RuleContext;
 import com.google.devtools.build.lib.analysis.actions.CustomCommandLine;
@@ -38,6 +43,9 @@
 import com.google.devtools.build.lib.skyframe.serialization.autocodec.AutoCodec;
 import com.google.devtools.build.lib.util.LazyString;
 import com.google.devtools.build.lib.vfs.PathFragment;
+import com.google.devtools.build.lib.view.proto.Deps;
+import java.io.IOException;
+import java.io.InputStream;
 import java.util.ArrayList;
 import java.util.Collection;
 import javax.annotation.Nullable;
@@ -294,6 +302,36 @@
       }
     }
 
+    JavaConfiguration javaConfiguration =
+        ruleContext.getConfiguration().getFragment(JavaConfiguration.class);
+    if (javaConfiguration.inmemoryJdepsFiles()) {
+      builder.setExecutionInfo(
+          ImmutableMap.of(
+              ExecutionRequirements.REMOTE_EXECUTION_INLINE_OUTPUTS,
+              outputDepsProto.getExecPathString()));
+    }
+    builder.addResultConsumer(
+        contextAndResults -> {
+          ActionExecutionContext context = contextAndResults.getFirst();
+          JavaCompileActionContext javaContext = context.getContext(JavaCompileActionContext.class);
+          if (javaContext == null) {
+            return;
+          }
+          SpawnResult spawnResult = Iterables.getOnlyElement(contextAndResults.getSecond());
+          try {
+            InputStream inMemoryOutput = spawnResult.getInMemoryOutput(outputDepsProto);
+            try (InputStream input =
+                inMemoryOutput == null
+                    ? context.getInputPath(outputDepsProto).getInputStream()
+                    : inMemoryOutput) {
+              javaContext.insertDependencies(outputDepsProto, Deps.Dependencies.parseFrom(input));
+            }
+          } catch (IOException e) {
+            // Left empty. If we cannot read the .jdeps file now, we will read it later or throw
+            // an appropriate error then.
+          }
+        });
+
     // The action doesn't require annotation processing, so use the non-javac-based turbine
     // implementation.
     if (!requiresAnnotationProcessing) {