1 files changed, 88 insertions, 0 deletions
diff --git a/src/java_tools/buildjar/java/com/google/devtools/build/buildjar/javac/BlazeJavacLog.java b/src/java_tools/buildjar/java/com/google/devtools/build/buildjar/javac/BlazeJavacLog.java
new file mode 100644
index 0000000000..6c0ee495fd
--- /dev/null
+++ b/src/java_tools/buildjar/java/com/google/devtools/build/buildjar/javac/BlazeJavacLog.java
@@ -0,0 +1,88 @@
+// Copyright 2014 Google Inc. 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.buildjar.javac;
+
+import com.sun.tools.javac.util.Context;
+import com.sun.tools.javac.util.JCDiagnostic;
+import com.sun.tools.javac.util.Log;
+
+/**
+ * Log class for our custom patched javac.
+ *
+ * <p> This log class tweaks the standard javac log class so
+ * that it drops all non-errors after the first error that
+ * gets reported. By doing this, we
+ * ensure that all warnings are listed before all errors in javac's
+ * output. This makes life easier for everybody.
+ */
+public class BlazeJavacLog extends Log {
+
+  private boolean hadError = false;
+
+  /**
+   * Registers a custom BlazeJavacLog for the given context and -Werror spec.
+   *
+   * @param context Context
+   * @param warningsAsErrors Werror value
+   */
+  public static void preRegister(final Context context) {
+    context.put(logKey, new Context.Factory<Log>() {
+      @Override
+      public Log make(Context c) {
+        return new BlazeJavacLog(c);
+      }
+    });
+  }
+
+  public static BlazeJavacLog instance(Context context) {
+    return (BlazeJavacLog) context.get(logKey);
+  }
+
+  BlazeJavacLog(Context context) {
+    super(context);
+  }
+
+  /**
+   * Returns true if we should display the note diagnostic
+   * passed in as argument, and false if we should discard
+   * it.
+   */
+  private boolean shouldDisplayNote(JCDiagnostic diag) {
+    String noteCode = diag.getCode();
+    return noteCode == null ||
+        (!noteCode.startsWith("compiler.note.deprecated") &&
+         !noteCode.startsWith("compiler.note.unchecked"));
+  }
+
+  @Override
+  protected void writeDiagnostic(JCDiagnostic diag) {
+    switch (diag.getKind()) {
+      case NOTE:
+        if (shouldDisplayNote(diag)) {
+          super.writeDiagnostic(diag);
+        }
+        break;
+      case ERROR:
+        hadError = true;
+        super.writeDiagnostic(diag);
+        break;
+      default:
+        if (!hadError) {
+          // Do not print further warnings if an error has occured.
+          super.writeDiagnostic(diag);
+        }
+    }
+  }
+}