Fix exception message

* Add message for exception thrown when redefining custom proto adapter
Faire · Jun 27, 2016 · 7b2d875 · 7b2d875
1 parent 931a235
commit 7b2d875
Showing 1 changed file with 1 addition and 1 deletion.
diff --git a/wire-java-generator/src/main/java/com/squareup/wire/java/JavaGenerator.java b/wire-java-generator/src/main/java/com/squareup/wire/java/JavaGenerator.java
@@ -195,7 +195,7 @@ public JavaGenerator withCustomProtoAdapter(
       ImmutableMap<ProtoType, ClassName> protoTypeToCustomJavaName,
       ImmutableMap<ProtoType, AdapterConstant> protoTypeToAdapterConstant) {
     if (!this.nameToProtoFieldsJavaName.isEmpty()) {
-      throw new IllegalStateException();
+      throw new IllegalStateException("Redefining custom proto adapter is illegal.");
     }
 
     Map<ProtoType, ClassName> nameToJavaName = new LinkedHashMap<>(this.nameToJavaName);