--- /dev/null	2015-04-26 06:51:08.003313989 -0700
+++ new/jdk/src/jdk.internal.le/share/classes/jdk/internal/jline/internal/Log.java	2015-06-25 08:33:17.789422953 -0700
@@ -0,0 +1,120 @@
+/*
+ * Copyright (c) 2002-2012, the original author or authors.
+ *
+ * This software is distributable under the BSD license. See the terms of the
+ * BSD license in the documentation provided with this software.
+ *
+ * http://www.opensource.org/licenses/bsd-license.php
+ */
+package jdk.internal.jline.internal;
+
+import java.io.PrintStream;
+
+import static jdk.internal.jline.internal.Preconditions.checkNotNull;
+
+/**
+ * Internal logger.
+ *
+ * @author <a href="mailto:jason@planet57.com">Jason Dillon</a>
+ * @since 2.0
+ */
+public final class Log
+{
+    ///CLOVER:OFF
+
+    public static enum Level
+    {
+        TRACE,
+        DEBUG,
+        INFO,
+        WARN,
+        ERROR
+    }
+
+    @SuppressWarnings({"StringConcatenation"})
+    public static final boolean TRACE = Boolean.getBoolean(Log.class.getName() + ".trace");
+
+    @SuppressWarnings({"StringConcatenation"})
+    public static final boolean DEBUG = TRACE || Boolean.getBoolean(Log.class.getName() + ".debug");
+
+    private static PrintStream output = System.err;
+
+    public static PrintStream getOutput() {
+        return output;
+    }
+
+    public static void setOutput(final PrintStream out) {
+        output = checkNotNull(out);
+    }
+
+    /**
+     * Helper to support rendering messages.
+     */
+    @TestAccessible
+    static void render(final PrintStream out, final Object message) {
+        if (message.getClass().isArray()) {
+            Object[] array = (Object[]) message;
+
+            out.print("[");
+            for (int i = 0; i < array.length; i++) {
+                out.print(array[i]);
+                if (i + 1 < array.length) {
+                    out.print(",");
+                }
+            }
+            out.print("]");
+        }
+        else {
+            out.print(message);
+        }
+    }
+
+    @TestAccessible
+    static void log(final Level level, final Object... messages) {
+        //noinspection SynchronizeOnNonFinalField
+        synchronized (output) {
+            output.format("[%s] ", level);
+
+            for (int i=0; i<messages.length; i++) {
+                // Special handling for the last message if its a throwable, render its stack on the next line
+                if (i + 1 == messages.length && messages[i] instanceof Throwable) {
+                    output.println();
+                    ((Throwable)messages[i]).printStackTrace(output);
+                }
+                else {
+                    render(output, messages[i]);
+                }
+            }
+
+            output.println();
+            output.flush();
+        }
+    }
+
+    public static void trace(final Object... messages) {
+        if (TRACE) {
+            log(Level.TRACE, messages);
+        }
+    }
+
+    public static void debug(final Object... messages) {
+        if (TRACE || DEBUG) {
+            log(Level.DEBUG, messages);
+        }
+    }
+
+    /**
+     * @since 2.7
+     */
+    public static void info(final Object... messages) {
+        log(Level.INFO, messages);
+    }
+
+    public static void warn(final Object... messages) {
+        log(Level.WARN, messages);
+    }
+
+    public static void error(final Object... messages) {
+        log(Level.ERROR, messages);
+    }
+}