From 5501fcae57188560b0fea61a51b3efc5b0313be5 Mon Sep 17 00:00:00 2001
From: Benedict Wong <benedictwong@google.com>
Date: Mon, 28 Oct 2019 19:03:05 -0700
Subject: [PATCH] Add message template support for checkStringNotEmpty

This change adds the ability for the Preconditions#checkStringNotEmpty()
to take a message template instead of just an error message, allowing
for template reuse.

Test: FrameworksNetTests passing
Change-Id: I6df1c3bff77b227126c35f066ee9112e959d6b1c
---
 .../android/internal/util/Preconditions.java   | 18 ++++++++++++++++++
 1 file changed, 18 insertions(+)

diff --git a/core/java/com/android/internal/util/Preconditions.java b/core/java/com/android/internal/util/Preconditions.java
index 731b93c18b093..3fff5c233890f 100644
--- a/core/java/com/android/internal/util/Preconditions.java
+++ b/core/java/com/android/internal/util/Preconditions.java
@@ -101,6 +101,24 @@ public class Preconditions {
         return string;
     }
 
+    /**
+     * Ensures that an string reference passed as a parameter to the calling method is not empty.
+     *
+     * @param string an string reference
+     * @param messageTemplate a printf-style message template to use if the check fails; will be
+     *     converted to a string using {@link String#format(String, Object...)}
+     * @param messageArgs arguments for {@code messageTemplate}
+     * @return the string reference that was validated
+     * @throws IllegalArgumentException if {@code string} is empty
+     */
+    public static @NonNull <T extends CharSequence> T checkStringNotEmpty(
+            final T string, final String messageTemplate, final Object... messageArgs) {
+        if (TextUtils.isEmpty(string)) {
+            throw new IllegalArgumentException(String.format(messageTemplate, messageArgs));
+        }
+        return string;
+    }
+
     /**
      * Ensures that an object reference passed as a parameter to the calling
      * method is not null.