reset position in Strings.encode

esaulpaugh · Aug 21, 2024 · 1a4606b · 1a4606b
1 parent 9604408
commit 1a4606b
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Showing 2 changed files with 17 additions and 22 deletions.
diff --git a/src/main/java/com/esaulpaugh/headlong/util/Strings.java b/src/main/java/com/esaulpaugh/headlong/util/Strings.java
@@ -37,16 +37,15 @@ public static String encode(byte b) {
         return encode(new byte[] { b });
     }
 
-    public static String encode(ByteBuffer buffer) {
-        final byte[] bytes;
-        if (buffer.hasArray()) {
-            bytes = buffer.array();
+    public static String encode(ByteBuffer buf) {
+        if (buf.hasArray()) {
+            return encode(buf.array());
         } else {
-            buffer.position(0);
-            bytes = new byte[buffer.capacity()];
-            buffer.get(bytes);
+            final int pos = buf.position();
+            byte[] bytes = new byte[buf.position(0).limit()];
+            buf.get(bytes).position(pos);
+            return encode(bytes);
         }
-        return encode(bytes);
     }
 
     public static String encode(byte[] bytes) {

diff --git a/src/test/java/com/esaulpaugh/headlong/util/StringsTest.java b/src/test/java/com/esaulpaugh/headlong/util/StringsTest.java
@@ -49,24 +49,20 @@ private static void testEncoding(int n, int encoding, Supplier<byte[]> supplier)
 
     @Test
     public void testEncodeDirectBuffer() {
-        final int len = RAND.nextInt(257);
-        final ByteBuffer ro = ByteBuffer.allocateDirect(len);
-        assertTrue(ro.isDirect());
-        final String hex = Strings.encode(ro);
-        assertEquals(len * 2, hex.length());
-        for (int i = 0; i < len; i += 2) {
-            if (hex.charAt(i) != '0' || hex.charAt(i + 1) != '0') {
-                throw new AssertionError("" + i);
-            }
-        }
+        testEncodeBuffer(ByteBuffer.allocateDirect(RAND.nextInt(257)));
     }
 
     @Test
     public void testEncodeReadOnlyBuffer() {
-        final int len = RAND.nextInt(257);
-        final ByteBuffer ro = ByteBuffer.allocate(len).asReadOnlyBuffer();
-        assertTrue(ro.isReadOnly());
-        final String hex = Strings.encode(ro);
+        testEncodeBuffer(ByteBuffer.allocate(RAND.nextInt(257)).asReadOnlyBuffer());
+    }
+
+    private void testEncodeBuffer(ByteBuffer bb) {
+        final int len = bb.capacity();
+        final int pos = RAND.nextInt(len + 1);
+        bb.position(pos);
+        final String hex = Strings.encode(bb);
+        assertEquals(pos, bb.position());
         assertEquals(len * 2, hex.length());
         for (int i = 0; i < len; i += 2) {
             if (hex.charAt(i) != '0' || hex.charAt(i + 1) != '0') {