diff --git a/core/src/main/java/com/google/errorprone/bugpatterns/UnsafeLocaleUsage.java b/core/src/main/java/com/google/errorprone/bugpatterns/UnsafeLocaleUsage.java
index 1746c86ab6f..442f01bab4e 100644
--- a/core/src/main/java/com/google/errorprone/bugpatterns/UnsafeLocaleUsage.java
+++ b/core/src/main/java/com/google/errorprone/bugpatterns/UnsafeLocaleUsage.java
@@ -84,10 +84,9 @@ public Description matchNewClass(NewClassTree tree, VisitorState state) {
         String replacementArg =
             arg instanceof JCLiteral
                 ? String.format(
-                    "\"%s\"", ASTHelpers.constValue(arg, String.class).replace("_", "-"))
+                    "\"%s\"", ASTHelpers.constValue(arg, String.class).replace('_', '-'))
                 : String.format(
-                    "%s.replace(\"_\", \"-\")",
-                    state.getSourceForNode(constructorArguments.get(0)));
+                    "%s.replace('_', '-')", state.getSourceForNode(constructorArguments.get(0)));
 
         descriptionBuilder.addFix(
             SuggestedFix.replace(tree, String.format("Locale.forLanguageTag(%s)", replacementArg)));
diff --git a/core/src/test/java/com/google/errorprone/bugpatterns/UnsafeLocaleUsageTest.java b/core/src/test/java/com/google/errorprone/bugpatterns/UnsafeLocaleUsageTest.java
index a690f816147..fbcee7a2c31 100644
--- a/core/src/test/java/com/google/errorprone/bugpatterns/UnsafeLocaleUsageTest.java
+++ b/core/src/test/java/com/google/errorprone/bugpatterns/UnsafeLocaleUsageTest.java
@@ -60,7 +60,7 @@ class Test {
               static class Inner {
                 private Locale locale;
                 Inner(String a) {
-                   locale = Locale.forLanguageTag(a.replace("_", "-"));
+                   locale = Locale.forLanguageTag(a.replace('_', '-'));
                 }
               }