Remove some usages of IoUtil methods

Continuing the long process of shrinking the core platform API
by switching users, particularly tests, to alternatives.

Bug: 124232146
Test: atest CtsLibcoreTestCases:libcore.android.system.OsTest
Change-Id: If1a473f4d7a120723602faa70129ead1bf8ebc64

1 files changed, 11 insertions, 0 deletions

diff --git a/support/src/test/java/libcore/testing/io/TestIoUtils.java b/support/src/test/java/libcore/testing/io/TestIoUtils.java
index 8e241df050..34a2cf7d4d 100644
--- a/support/src/test/java/libcore/testing/io/TestIoUtils.java
+++ b/support/src/test/java/libcore/testing/io/TestIoUtils.java
@@ -17,6 +17,10 @@
 package libcore.testing.io;
 
 import java.io.File;
+import java.io.IOException;
+import java.nio.charset.StandardCharsets;
+import java.nio.file.Files;
+import java.nio.file.Paths;
 import java.util.Random;
 
 public class TestIoUtils {
@@ -25,6 +29,13 @@ public class TestIoUtils {
     private TestIoUtils() {}
 
     /**
+     * Returns the contents of 'path' as a string. The contents are assumed to be UTF-8.
+     */
+    public static String readFileAsString(String absolutePath) throws IOException {
+        return new String(Files.readAllBytes(Paths.get(absolutePath)), StandardCharsets.UTF_8);
+    }
+
+    /**
      * Creates a unique new temporary directory under "java.io.tmpdir".
      */
     public static File createTemporaryDirectory(String prefix) {