--- a/langtools/test/tools/javac/4846262/CheckEBCDICLocaleTest.java	Fri May 22 13:05:26 2015 +0200
+++ b/langtools/test/tools/javac/4846262/CheckEBCDICLocaleTest.java	Fri May 22 16:44:49 2015 -0700
@@ -34,6 +34,7 @@
  */
 
 import java.io.File;
+import java.nio.charset.Charset;
 import java.nio.file.Files;
 import java.nio.file.Path;
 import java.nio.file.Paths;
@@ -64,14 +65,11 @@
 
     public void test() throws Exception {
         ToolBox tb = new ToolBox();
-        Path native2asciiBinary = tb.getJDKTool("native2ascii");
-
         tb.writeFile("Test.java", TestSrc);
         tb.createDirectories("output");
 
-        tb.new ExecTask(native2asciiBinary)
-                .args("-reverse", "-encoding", "IBM1047", "Test.java", "output/Test.java")
-                .run();
+        Native2Ascii n2a = new Native2Ascii(Charset.forName("IBM1047"));
+        n2a.asciiToNative(Paths.get("Test.java"), Paths.get("output", "Test.java"));
 
         tb.new JavacTask(ToolBox.Mode.EXEC)
                 .redirect(ToolBox.OutputKind.STDERR, "Test.tmp")
@@ -81,14 +79,11 @@
                 .files("output/Test.java")
                 .run(ToolBox.Expect.FAIL);
 
-        tb.new ExecTask(native2asciiBinary)
-                .args("-encoding", "IBM1047", "Test.tmp", "Test.out")
-                .run();
+        n2a.nativeToAscii(Paths.get("Test.tmp"), Paths.get("Test.out"));
 
         List<String> expectLines = Arrays.asList(
                 String.format(TestOutTemplate, File.separator).split("\n"));
         List<String> actualLines = Files.readAllLines(Paths.get("Test.out"));
         tb.checkEqual(expectLines, actualLines);
     }
-
 }

--- /dev/null	Thu Jan 01 00:00:00 1970 +0000
+++ b/langtools/test/tools/javac/4846262/Native2Ascii.java	Fri May 22 16:44:49 2015 -0700
@@ -0,0 +1,213 @@
+/*
+ * Copyright (c) 2015, 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.BufferedReader;
+import java.io.BufferedWriter;
+import java.io.FilterReader;
+import java.io.FilterWriter;
+import java.io.IOException;
+import java.io.Reader;
+import java.io.Writer;
+import java.nio.charset.Charset;
+import java.nio.charset.CharsetEncoder;
+import java.nio.file.Files;
+import java.nio.file.Path;
+import static java.nio.charset.StandardCharsets.*;
+
+/**
+ * Simple utility to convert from native encoding file to ascii or reverse
+ * including \udddd Unicode notation.
+ */
+public class Native2Ascii {
+    final Charset cs;
+    final CharsetEncoder encoder;
+    public Native2Ascii(Charset cs) {
+        this.cs = cs;
+        this.encoder = cs.newEncoder();
+    }
+
+    /**
+     * ASCII to Native conversion
+     */
+    public void asciiToNative(Path infile, Path outfile) throws IOException {
+        try (BufferedReader in = Files.newBufferedReader(infile, US_ASCII);
+             BufferedReader reader = new BufferedReader(new A2NFilter(in));
+             BufferedWriter writer = Files.newBufferedWriter(outfile, cs)) {
+            String line;
+            while ((line = reader.readLine()) != null) {
+                writer.write(line.toCharArray());
+                writer.newLine();
+            }
+        }
+    }
+
+    /**
+     * Native to ASCII conversion
+     */
+    public void nativeToAscii(Path infile, Path outfile) throws IOException {
+        try (BufferedReader reader = Files.newBufferedReader(infile, cs);
+             BufferedWriter out = Files.newBufferedWriter(outfile, US_ASCII);
+             BufferedWriter writer = new BufferedWriter(new N2AFilter(out))) {
+            String line;
+            while ((line = reader.readLine()) != null) {
+                writer.write(line.toCharArray());
+                writer.newLine();
+            }
+        }
+    }
+
+    // A copy of native2ascii N2AFilter
+    class N2AFilter extends FilterWriter {
+        public N2AFilter(Writer out) { super(out); }
+        public void write(char b) throws IOException {
+            char[] buf = new char[1];
+            buf[0] = b;
+            write(buf, 0, 1);
+        }
+
+        public void write(char[] buf, int off, int len) throws IOException {
+            for (int i = 0; i < len; i++) {
+                if ((buf[i] > '\u007f')) {
+                    // write \udddd
+                    out.write('\\');
+                    out.write('u');
+                    String hex = Integer.toHexString(buf[i]);
+                    StringBuilder hex4 = new StringBuilder(hex);
+                    hex4.reverse();
+                    int length = 4 - hex4.length();
+                    for (int j = 0; j < length; j++) {
+                        hex4.append('0');
+                    }
+                    for (int j = 0; j < 4; j++) {
+                        out.write(hex4.charAt(3 - j));
+                    }
+                } else
+                    out.write(buf[i]);
+            }
+        }
+    }
+
+    // A copy of native2ascii A2NFilter
+    class A2NFilter extends FilterReader {
+        // maintain a trailing buffer to hold any incompleted
+        // unicode escaped sequences
+        private char[] trailChars = null;
+
+        public A2NFilter(Reader in) {
+            super(in);
+        }
+
+        public int read(char[] buf, int off, int len) throws IOException {
+            int numChars = 0;        // how many characters have been read
+            int retChars = 0;        // how many characters we'll return
+
+            char[] cBuf = new char[len];
+            int cOffset = 0;         // offset at which we'll start reading
+            boolean eof = false;
+
+            // copy trailing chars from previous invocation to input buffer
+            if (trailChars != null) {
+                for (int i = 0; i < trailChars.length; i++)
+                    cBuf[i] = trailChars[i];
+                numChars = trailChars.length;
+                trailChars = null;
+            }
+
+            int n = in.read(cBuf, numChars, len - numChars);
+            if (n < 0) {
+                eof = true;
+                if (numChars == 0)
+                    return -1;              // EOF;
+            } else {
+                numChars += n;
+            }
+
+            for (int i = 0; i < numChars; ) {
+                char c = cBuf[i++];
+
+                if (c != '\\' || (eof && numChars <= 5)) {
+                    // Not a backslash, so copy and continue
+                    // Always pass non backslash chars straight thru
+                    // for regular encoding. If backslash occurs in
+                    // input stream at the final 5 chars then don't
+                    // attempt to read-ahead and de-escape since these
+                    // are literal occurrences of U+005C which need to
+                    // be encoded verbatim in the target encoding.
+                    buf[retChars++] = c;
+                    continue;
+                }
+
+                int remaining = numChars - i;
+                if (remaining < 5) {
+                    // Might be the first character of a unicode escape, but we
+                    // don't have enough characters to tell, so save it and finish
+                    trailChars = new char[1 + remaining];
+                    trailChars[0] = c;
+                    for (int j = 0; j < remaining; j++)
+                        trailChars[1 + j] = cBuf[i + j];
+                    break;
+                }
+                // At this point we have at least five characters remaining
+
+                c = cBuf[i++];
+                if (c != 'u') {
+                    // Not a unicode escape, so copy and continue
+                    buf[retChars++] = '\\';
+                    buf[retChars++] = c;
+                    continue;
+                }
+
+                // The next four characters are the hex part of a unicode escape
+                char rc = 0;
+                boolean isUE = true;
+                try {
+                    rc = (char) Integer.parseInt(new String(cBuf, i, 4), 16);
+                } catch (NumberFormatException x) {
+                    isUE = false;
+                }
+                if (isUE && encoder.canEncode(rc)) {
+                    // We'll be able to convert this
+                    buf[retChars++] = rc;
+                    i += 4; // Align beyond the current uXXXX sequence
+                } else {
+                    // We won't, so just retain the original sequence
+                    buf[retChars++] = '\\';
+                    buf[retChars++] = 'u';
+                    continue;
+                }
+
+            }
+
+            return retChars;
+        }
+
+        public int read() throws IOException {
+            char[] buf = new char[1];
+
+            if (read(buf, 0, 1) == -1)
+                return -1;
+            else
+                return (int) buf[0];
+        }
+    }
+}