Don't fail the build if compiling a module without direct jars.

Closes #18

Author: guw

compiler/src/main/buildjar/com/google/devtools/build/buildjar/BazelEcjJavaBuilder.java

@@ -14,6 +14,8 @@
 
 package com.google.devtools.build.buildjar;
 
+import static com.google.devtools.build.buildjar.StrictDepsClasspathJavaLibraryBuilder.OPTION_STRICT_DEPS_BUILDER;
+
 import java.io.IOException;
 import java.io.OutputStreamWriter;
 import java.io.PrintWriter;
@@ -28,7 +30,6 @@
 import com.google.common.collect.ImmutableList;
 import com.google.devtools.build.buildjar.javac.BlazeJavacResult;
 import com.google.devtools.build.buildjar.javac.BlazeJavacResult.Status;
-import com.google.devtools.build.buildjar.javac.FormattedDiagnostic;
 import com.google.devtools.build.buildjar.javac.JavacOptions;
 import com.google.devtools.build.buildjar.javac.plugins.BlazeJavaCompilerPlugin;
 import com.google.devtools.build.buildjar.javac.plugins.dependency.DependencyModule;
@@ -90,7 +91,7 @@ public int parseAndBuild(List<String> args, PrintWriter pw) {
   }
 
   private Supplier<SimpleJavaLibraryBuilder> getBuilder(JavaLibraryBuildRequest build) {
-    if(build.getJavacOpts().contains("-Xecj_use_direct_deps_only"))
+    if(build.getJavacOpts().contains(OPTION_STRICT_DEPS_BUILDER))
       return StrictDepsClasspathJavaLibraryBuilder::new;
     return build.getDependencyModule().reduceClasspath()
         ? ReducedClasspathJavaLibraryBuilder::new

compiler/src/main/buildjar/com/google/devtools/build/buildjar/StrictDepsClasspathJavaLibraryBuilder.java

@@ -31,6 +31,8 @@
  */
 public class StrictDepsClasspathJavaLibraryBuilder extends SimpleJavaLibraryBuilder {
 
+	static final String OPTION_STRICT_DEPS_BUILDER = "-Xecj_use_direct_deps_only";
+
 	/**
 	 * Attempts to minimize the compile-time classpath before invoking javac,
 	 * falling back to a regular compile.
@@ -41,13 +43,20 @@ public class StrictDepsClasspathJavaLibraryBuilder extends SimpleJavaLibraryBuil
 	 */
 	@Override
 	BlazeJavacResult compileSources(JavaLibraryBuildRequest build, JavacRunner javacRunner) throws IOException {
-		if(build.getDependencyModule().directJars().isEmpty()) {
-			// in this case the direct jars list is empty
-			return BlazeJavacResult.error("No direct jars information supplied by Bazel. Please adjust Bazel settings to allow submission of direct dependency information (e.g., don't use --strict_java_deps=off).");
-		}
+		ImmutableList<Path> compressedClasspath;
+		switch (build.getDependencyModule().getStrictJavaDeps()) {
+		case OFF:
+			// this does nor really make sense but the user selected to do so
+			compressedClasspath = build.getClassPath();
+			break;
 
-		ImmutableList<Path> compressedClasspath = build.getDependencyModule().directJars().stream()
-				.collect(toImmutableList());
+		case ERROR:
+		case WARN:
+		default:
+			// compile with the direct jars only
+			compressedClasspath = build.getDependencyModule().directJars().stream().collect(toImmutableList());
+			break;
+		}
 
 		BlazeJavacResult result = javacRunner.invokeJavac(build.toBlazeJavacArguments(compressedClasspath));