Strip down PackageDeserializer#Context

Make Context DeserializationContext, use as a dumb container object for
one-time-use deserialization. The previous organization was imbalanced-
some deserialization was done by context, other was done by PackageDeserializer.
This will make it easer to add more context and make it available to
more parts of deserialization.

--
MOS_MIGRATED_REVID=100690973

1 files changed, 86 insertions, 84 deletions

diff --git a/src/main/java/com/google/devtools/build/lib/packages/PackageDeserializer.java b/src/main/java/com/google/devtools/build/lib/packages/PackageDeserializer.java
index d48c5e6bfe..3d4ab28cf6 100644
--- a/src/main/java/com/google/devtools/build/lib/packages/PackageDeserializer.java
+++ b/src/main/java/com/google/devtools/build/lib/packages/PackageDeserializer.java
@@ -75,89 +75,103 @@ public class PackageDeserializer {
   // TODO(bazel-team): Subclass ObjectOutputStream to pass this through instead.
   public static volatile PackageDeserializationEnvironment defaultPackageDeserializationEnvironment;
 
-  private class Context {
+  /** Class encapsulating state for a single package deserialization. */
+  private static class DeserializationContext {
     private final Package.Builder packageBuilder;
     private final PathFragment buildFilePath;
 
-    public Context(Path buildFilePath, Package.Builder packageBuilder) {
+    public DeserializationContext(Path buildFilePath, Package.Builder packageBuilder) {
       this.buildFilePath = buildFilePath.asFragment();
       this.packageBuilder = packageBuilder;
     }
+  }
 
-    Location deserializeLocation(Build.Location location) {
-      return new ExplicitLocation(buildFilePath, location);
-    }
+  private final PackageDeserializationEnvironment packageDeserializationEnvironment;
 
-    ParsedAttributeValue deserializeAttribute(Type<?> expectedType,
-        Build.Attribute attrPb)
-        throws PackageDeserializationException {
-      Object value = deserializeAttributeValue(expectedType, attrPb);
-      return new ParsedAttributeValue(
-          attrPb.hasExplicitlySpecified() && attrPb.getExplicitlySpecified(), value,
-          deserializeLocation(attrPb.getParseableLocation()));
-    }
+  /**
+   * Creates a {@link PackageDeserializer} using {@link #defaultPackageDeserializationEnvironment}.
+   */
+  public PackageDeserializer() {
+    this.packageDeserializationEnvironment = defaultPackageDeserializationEnvironment;
+  }
 
-    void deserializeInputFile(Build.SourceFile sourceFile)
-        throws PackageDeserializationException {
-      InputFile inputFile;
-      try {
-        inputFile = packageBuilder.createInputFile(
-            deserializeLabel(sourceFile.getName()).getName(),
-            deserializeLocation(sourceFile.getParseableLocation()));
-      } catch (GeneratedLabelConflict e) {
-        throw new PackageDeserializationException(e);
-      }
+  public PackageDeserializer(PackageDeserializationEnvironment packageDeserializationEnvironment) {
+    this.packageDeserializationEnvironment =
+        Preconditions.checkNotNull(packageDeserializationEnvironment);
+  }
 
-      if (!sourceFile.getVisibilityLabelList().isEmpty() || sourceFile.hasLicense()) {
-        packageBuilder.setVisibilityAndLicense(inputFile,
-            PackageFactory.getVisibility(deserializeLabels(sourceFile.getVisibilityLabelList())),
-            deserializeLicense(sourceFile.getLicense()));
-      }
-    }
+  private static Location deserializeLocation(DeserializationContext context,
+      Build.Location location) {
+    return new ExplicitLocation(context.buildFilePath, location);
+  }
 
-    void deserializePackageGroup(Build.PackageGroup packageGroupPb)
-        throws PackageDeserializationException {
-      List<String> specifications = new ArrayList<>();
-      for (String containedPackage : packageGroupPb.getContainedPackageList()) {
-        specifications.add("//" + containedPackage);
-      }
+  private static ParsedAttributeValue deserializeAttribute(DeserializationContext context,
+      Type<?> expectedType, Build.Attribute attrPb) throws PackageDeserializationException {
+    Object value = deserializeAttributeValue(expectedType, attrPb);
+    return new ParsedAttributeValue(
+        attrPb.hasExplicitlySpecified() && attrPb.getExplicitlySpecified(), value,
+        deserializeLocation(context, attrPb.getParseableLocation()));
+  }
 
-      try {
-        packageBuilder.addPackageGroup(
-            deserializeLabel(packageGroupPb.getName()).getName(),
-            specifications,
-            deserializeLabels(packageGroupPb.getIncludedPackageGroupList()),
-            NullEventHandler.INSTANCE,  // TODO(bazel-team): Handle errors properly
-            deserializeLocation(packageGroupPb.getParseableLocation()));
-      } catch (Label.SyntaxException | Package.NameConflictException e) {
-        throw new PackageDeserializationException(e);
-      }
+  private void deserializeInputFile(DeserializationContext context, Build.SourceFile sourceFile)
+      throws PackageDeserializationException {
+    InputFile inputFile;
+    try {
+      inputFile = context.packageBuilder.createInputFile(
+          deserializeLabel(sourceFile.getName()).getName(),
+          deserializeLocation(context, sourceFile.getParseableLocation()));
+    } catch (GeneratedLabelConflict e) {
+      throw new PackageDeserializationException(e);
     }
 
-    void deserializeRule(Build.Rule rulePb) throws PackageDeserializationException {
-      Location ruleLocation = deserializeLocation(rulePb.getParseableLocation());
-      RuleClass ruleClass = packageDeserializationEnvironment.getRuleClass(rulePb, ruleLocation);
-      Map<String, ParsedAttributeValue> attributeValues = new HashMap<>();
-      for (Build.Attribute attrPb : rulePb.getAttributeList()) {
-        Type<?> type = ruleClass.getAttributeByName(attrPb.getName()).getType();
-        attributeValues.put(attrPb.getName(), deserializeAttribute(type, attrPb));
-      }
+    if (!sourceFile.getVisibilityLabelList().isEmpty() || sourceFile.hasLicense()) {
+      context.packageBuilder.setVisibilityAndLicense(inputFile,
+          PackageFactory.getVisibility(deserializeLabels(sourceFile.getVisibilityLabelList())),
+          deserializeLicense(sourceFile.getLicense()));
+    }
+  }
 
-      Label ruleLabel = deserializeLabel(rulePb.getName());
-      try {
-        Rule rule = ruleClass.createRuleWithParsedAttributeValues(
-            ruleLabel, packageBuilder, ruleLocation, attributeValues,
-            NullEventHandler.INSTANCE);
-        packageBuilder.addRule(rule);
+  private void deserializePackageGroup(DeserializationContext context,
+      Build.PackageGroup packageGroupPb) throws PackageDeserializationException {
+    List<String> specifications = new ArrayList<>();
+    for (String containedPackage : packageGroupPb.getContainedPackageList()) {
+      specifications.add("//" + containedPackage);
+    }
 
-        Preconditions.checkState(!rule.containsErrors());
-      } catch (NameConflictException | SyntaxException e) {
-        throw new PackageDeserializationException(e);
-      }
+    try {
+      context.packageBuilder.addPackageGroup(
+          deserializeLabel(packageGroupPb.getName()).getName(),
+          specifications,
+          deserializeLabels(packageGroupPb.getIncludedPackageGroupList()),
+          NullEventHandler.INSTANCE,  // TODO(bazel-team): Handle errors properly
+          deserializeLocation(context, packageGroupPb.getParseableLocation()));
+    } catch (Label.SyntaxException | Package.NameConflictException e) {
+      throw new PackageDeserializationException(e);
     }
   }
 
-  private final PackageDeserializationEnvironment packageDeserializationEnvironment;
+  private void deserializeRule(DeserializationContext context, Build.Rule rulePb)
+      throws PackageDeserializationException {
+    Location ruleLocation = deserializeLocation(context, rulePb.getParseableLocation());
+    RuleClass ruleClass = packageDeserializationEnvironment.getRuleClass(rulePb, ruleLocation);
+    Map<String, ParsedAttributeValue> attributeValues = new HashMap<>();
+    for (Build.Attribute attrPb : rulePb.getAttributeList()) {
+      Type<?> type = ruleClass.getAttributeByName(attrPb.getName()).getType();
+      attributeValues.put(attrPb.getName(), deserializeAttribute(context, type, attrPb));
+    }
+
+    Label ruleLabel = deserializeLabel(rulePb.getName());
+    try {
+      Rule rule = ruleClass.createRuleWithParsedAttributeValues(
+          ruleLabel, context.packageBuilder, ruleLocation, attributeValues,
+          NullEventHandler.INSTANCE);
+      context.packageBuilder.addRule(rule);
+
+      Preconditions.checkState(!rule.containsErrors());
+    } catch (NameConflictException | SyntaxException e) {
+      throw new PackageDeserializationException(e);
+    }
+  }
 
   @Immutable
   private static final class ExplicitLocation extends Location {
@@ -223,18 +237,6 @@ public class PackageDeserializer {
   }
 
   /**
-   * Creates a {@link PackageDeserializer} using {@link #defaultPackageDeserializationEnvironment}.
-   */
-  public PackageDeserializer() {
-    this.packageDeserializationEnvironment = defaultPackageDeserializationEnvironment;
-  }
-
-  public PackageDeserializer(PackageDeserializationEnvironment packageDeserializationEnvironment) {
-    this.packageDeserializationEnvironment =
-        Preconditions.checkNotNull(packageDeserializationEnvironment);
-  }
-
-  /**
    * Exception thrown when something goes wrong during package deserialization.
    */
   public static class PackageDeserializationException extends Exception {
@@ -339,7 +341,7 @@ public class PackageDeserializer {
       Package.Builder builder, InputStream in) throws PackageDeserializationException, IOException {
     Path buildFile = packageDeserializationEnvironment.getPath(packagePb.getBuildFilePath());
     Preconditions.checkNotNull(buildFile);
-    Context context = new Context(buildFile, builder);
+    DeserializationContext context = new DeserializationContext(buildFile, builder);
     builder.setFilename(buildFile);
 
     if (packagePb.hasDefaultVisibilitySet() && packagePb.getDefaultVisibilitySet()) {
@@ -401,20 +403,20 @@ public class PackageDeserializer {
     deserializeTargets(in, context);
   }
 
-  private static void deserializeTargets(InputStream in, Context context) throws IOException,
-      PackageDeserializationException {
+  private void deserializeTargets(InputStream in, DeserializationContext context)
+      throws IOException, PackageDeserializationException {
     Build.TargetOrTerminator tot;
     while (!(tot = Build.TargetOrTerminator.parseDelimitedFrom(in)).getIsTerminator()) {
       Build.Target target = tot.getTarget();
       switch (target.getType()) {
         case SOURCE_FILE:
-          context.deserializeInputFile(target.getSourceFile());
+          deserializeInputFile(context, target.getSourceFile());
           break;
         case PACKAGE_GROUP:
-          context.deserializePackageGroup(target.getPackageGroup());
+          deserializePackageGroup(context, target.getPackageGroup());
           break;
         case RULE:
-          context.deserializeRule(target.getRule());
+          deserializeRule(context, target.getRule());
           break;
         default:
           throw new IllegalStateException("Unexpected Target type: " + target.getType());
@@ -465,10 +467,10 @@ public class PackageDeserializer {
   }
 
   private static void deserializeEvent(
-      Context context, StoredEventHandler eventHandler, Build.Event event) {
+      DeserializationContext context, StoredEventHandler eventHandler, Build.Event event) {
     Location location = null;
     if (event.hasLocation()) {
-      location = context.deserializeLocation(event.getLocation());
+      location = deserializeLocation(context, event.getLocation());
     }
 
     String message = event.getMessage();