diff -r e3dcdd73a549 -r d51e64840b4f test/jdk/sun/nio/cs/EUCTWBufferBoundaryDecodeTest.java
--- /dev/null	Thu Jan 01 00:00:00 1970 +0000
+++ b/test/jdk/sun/nio/cs/EUCTWBufferBoundaryDecodeTest.java	Wed Jan 31 12:04:53 2018 +0800
@@ -0,0 +1,88 @@
+/*
+ * Copyright (c) 2018, 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.
+ */
+
+/*
+ * @test
+ * @bug 4734607 4767225 4863613
+ * @summary Decode a file using EUC-TW, test for decode errors
+ * @modules jdk.charsets
+ * @run main EUCTWBufferBoundaryDecodeTest
+ */
+import java.io.BufferedReader;
+import java.io.BufferedWriter;
+import java.io.ByteArrayOutputStream;
+import java.io.File;
+import java.io.FileInputStream;
+import java.io.InputStreamReader;
+import java.io.OutputStreamWriter;
+
+/*
+ * Tests for decode errors in NIO EUC-TW decoder. 4734607 details
+ * decoding errors which occur when the input file > 8k in size
+ * and contains numerous US-ASCII range chars
+ */
+public class EUCTWBufferBoundaryDecodeTest {
+
+    public static void main(String[] args) throws Exception {
+        final String inputFileName
+                = System.getProperty("os.name").startsWith("Windows")
+                ? "tradChinese.win.po"
+                : "tradChinese.po";
+
+        ByteArrayOutputStream bos = new ByteArrayOutputStream(1024 * 120);
+
+        File inputFile = new File(System.getProperty("test.src"), inputFileName);
+        FileInputStream fis = new FileInputStream(inputFile);
+
+        // Decode the EUC_TW source file, re-encode it -- (roundtrip)
+        // input and output files ought to be byte for byte identical
+        BufferedReader bin
+                = new BufferedReader(new InputStreamReader(fis, "EUC_TW"));
+        BufferedWriter bout
+                = new BufferedWriter(new OutputStreamWriter(bos, "EUC-TW"));
+
+        String line = bin.readLine();
+
+        while (line != null) {
+            bout.write(line);
+            bout.newLine();
+            line = bin.readLine();
+        }
+
+        bout.close();
+        bin.close();
+
+        // Compare the output with the expected output byte by byte
+        byte[] outputBytes = bos.toByteArray();
+        int i = 0;
+        FileInputStream fi = new FileInputStream(inputFile);
+
+        while (i < outputBytes.length) {
+            byte b = (byte) fi.read();
+            if (b != outputBytes[i++]) {
+                throw new Exception("bug 4734607: test failed");
+            }
+        }
+        fi.close();
+    }
+}