8067870: Fix java.io.ObjectInputStream.PeekInputStream#skip

Reviewed-by: rriggs, alanb

jdk/src/java.base/share/classes/java/io/ObjectInputStream.java

@@ -2345,7 +2345,7 @@ public class ObjectInputStream
                 skipped++;
                 n--;
             }
-            return skipped + skip(n);
+            return skipped + in.skip(n);
         }
 
         public int available() throws IOException {

jdk/test/java/io/ObjectInputStream/PeekInputStreamTest.java

@@ -0,0 +1,91 @@
+/*
+ * Copyright (c) 2014, Oracle and/or its affiliates. All rights reserved.
+ * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
+ *
+ * This code is free software; you can redistribute it and/or modify it
+ * under the terms of the GNU General Public License version 2 only, as
+ * published by the Free Software Foundation.
+ *
+ * This code is distributed in the hope that it will be useful, but WITHOUT
+ * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
+ * FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License
+ * version 2 for more details (a copy is included in the LICENSE file that
+ * accompanied this code).
+ *
+ * You should have received a copy of the GNU General Public License version
+ * 2 along with this work; if not, write to the Free Software Foundation,
+ * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA.
+ *
+ * Please contact Oracle, 500 Oracle Parkway, Redwood Shores, CA 94065 USA
+ * or visit www.oracle.com if you need additional information or have any
+ * questions.
+ */
+
+import java.io.ByteArrayInputStream;
+import java.io.IOException;
+import java.io.InputStream;
+import java.lang.reflect.Constructor;
+import java.lang.reflect.Method;
+
+/*
+ * @test
+ * @bug 8067870
+ * @summary verifies java.io.ObjectInputStream.PeekInputStream.skip works
+ *          as intended
+ */
+public class PeekInputStreamTest {
+
+    public static void main(String[] args) throws ReflectiveOperationException,
+            IOException {
+
+        InputStream pin = createPeekInputStream(
+                new ByteArrayInputStream(new byte[]{1, 2, 3, 4}));
+        peek(pin);
+        if (pin.skip(1) != 1 || pin.read() != 2)
+            throw new AssertionError();
+
+        InputStream pin1 = createPeekInputStream(
+                new ByteArrayInputStream(new byte[]{1, 2, 3, 4}));
+        if (pin1.skip(1) != 1 || pin1.read() != 2)
+            throw new AssertionError();
+
+        InputStream pin2 = createPeekInputStream(
+                new ByteArrayInputStream(new byte[]{1, 2, 3, 4}));
+        if (pin2.skip(0) != 0 || pin2.read() != 1)
+            throw new AssertionError();
+
+        InputStream pin3 = createPeekInputStream(
+                new ByteArrayInputStream(new byte[]{1, 2, 3, 4}));
+        if (pin3.skip(2) != 2 || pin3.read() != 3)
+            throw new AssertionError();
+
+        InputStream pin4 = createPeekInputStream(
+                new ByteArrayInputStream(new byte[]{1, 2, 3, 4}));
+        if (pin4.skip(3) != 3 || pin4.read() != 4)
+            throw new AssertionError();
+
+        InputStream pin5 = createPeekInputStream(
+                new ByteArrayInputStream(new byte[]{1, 2, 3, 4}));
+        if (pin5.skip(16) != 4 || pin5.read() != -1)
+            throw new AssertionError();
+    }
+
+    private static InputStream createPeekInputStream(InputStream underlying)
+            throws ReflectiveOperationException {
+        Class<? extends InputStream> clazz =
+                Class.forName("java.io.ObjectInputStream$PeekInputStream")
+                        .asSubclass(InputStream.class);
+
+        Constructor<? extends InputStream> ctr =
+                clazz.getDeclaredConstructor(InputStream.class);
+        ctr.setAccessible(true);
+        return ctr.newInstance(underlying);
+    }
+
+    private static void peek(InputStream pin)
+            throws ReflectiveOperationException {
+        Method p = pin.getClass().getDeclaredMethod("peek");
+        p.setAccessible(true);
+        p.invoke(pin);
+    }
+}