8005788: Loggers and their corresponding system properties not working correctly

Summary: 1-1 mapping now maintained. Used Context err instead of System.err in several places (after bootstrapping Context). Problematic closing of err stream replaced by @SuppressWarnings("resource")
Reviewed-by: jlaskey, sundar

src/jdk/nashorn/internal/ir/Symbol.java

@@ -27,6 +27,7 @@ package jdk.nashorn.internal.ir;
 
 import java.io.PrintWriter;
 import jdk.nashorn.internal.codegen.types.Type;
+import jdk.nashorn.internal.runtime.Context;
 import jdk.nashorn.internal.runtime.options.Options;
 
 /**
@@ -549,12 +550,7 @@ public final class Symbol implements Comparable<Symbol> {
      * @param slot valid bytecode slot, or -1 if not available
      */
     public void setSlot(final int slot) {
-        if (TRACE_SYMBOL != null) {
-            if (TRACE_SYMBOL.equals(name)) {
-                System.err.println(name + " gets slot " + slot);
-                new Throwable().printStackTrace();
-            }
-        }
+        trace("SET SLOT " + slot);
         this.slot = slot;
     }
 
@@ -574,18 +570,7 @@ public final class Symbol implements Comparable<Symbol> {
      * @param type the type
      */
     public void setType(final Type type) {
-        if (TRACE_SYMBOL == null) {
-            setTypeOverride(Type.widest(this.type, type));
-        } else {
-            final boolean check = TRACE_SYMBOL.equals(getName());
-            final Type from = this.type;
-            setTypeOverride(Type.widest(this.type, type));
-
-            if (check) {
-                System.err.println(getName() + " " + from + "=>" + type + " == " + this.type);
-                new Throwable().printStackTrace();
-            }
-        }
+        setTypeOverride(Type.widest(this.type, type));
     }
 
     /**
@@ -596,7 +581,11 @@ public final class Symbol implements Comparable<Symbol> {
      * @param type  the type
      */
     public void setTypeOverride(final Type type) {
-        this.type = type;
+        final Type old = this.type;
+        if (old != type) {
+            trace("TYPE CHANGE: " + old + "=>" + type + " == " + type);
+            this.type = type;
+        }
     }
 
     /**
@@ -607,4 +596,11 @@ public final class Symbol implements Comparable<Symbol> {
     public boolean isTopLevel() {
         return block instanceof FunctionNode && ((FunctionNode) block).isScript();
     }
+
+    private void trace(final String desc) {
+        if (TRACE_SYMBOL != null && TRACE_SYMBOL.equals(name)) {
+            Context.err("SYMBOL: '" + name + "' " + desc);
+            new Throwable().printStackTrace(Context.getContext().getErr());
+        }
+    }
 }

src/jdk/nashorn/internal/objects/NativeDebug.java

@@ -27,12 +27,13 @@ package jdk.nashorn.internal.objects;
 
 import static jdk.nashorn.internal.runtime.ScriptRuntime.UNDEFINED;
 
-import java.io.PrintStream;
+import java.io.PrintWriter;
 import java.util.Objects;
 import jdk.nashorn.internal.objects.annotations.Attribute;
 import jdk.nashorn.internal.objects.annotations.Function;
 import jdk.nashorn.internal.objects.annotations.ScriptClass;
 import jdk.nashorn.internal.objects.annotations.Where;
+import jdk.nashorn.internal.runtime.Context;
 import jdk.nashorn.internal.runtime.PropertyListenerManager;
 import jdk.nashorn.internal.runtime.PropertyMap;
 import jdk.nashorn.internal.runtime.ScriptFunction;
@@ -248,9 +249,11 @@ public class NativeDebug extends ScriptObject {
      * @param self self reference
      * @return undefined
      */
+    @SuppressWarnings("resource")
     @Function(attributes = Attribute.NOT_ENUMERABLE, where = Where.CONSTRUCTOR)
     public static Object dumpCounters(final Object self) {
-        final PrintStream out = System.err;
+        final PrintWriter out = Context.getContext().getErr();
+
         out.println("ScriptObject count " + ScriptObject.getCount());
         out.println("Scope count " + ScriptObject.getScopeCount());
         out.println("ScriptObject listeners added " + PropertyListenerManager.getListenersAdded());
@@ -268,7 +271,9 @@ public class NativeDebug extends ScriptObject {
         out.println("Callsite count " + LinkerCallSite.getCount());
         out.println("Callsite misses " + LinkerCallSite.getMissCount());
         out.println("Callsite misses by site at " + LinkerCallSite.getMissSamplingPercentage() + "%");
+
         LinkerCallSite.getMissCounts(out);
+
         return UNDEFINED;
     }
 }

src/jdk/nashorn/internal/runtime/Context.java

@@ -71,6 +71,12 @@ public final class Context {
             }
         };
 
+    /**
+     * Get the error stream if applicable and initialized, otherwise stderr
+     * Usually this is the error stream given the context, but for testing and
+     * certain bootstrapping situations we need a default stream
+     */
+
     /**
      * Return the current global scope
      * @return current global scope
@@ -119,20 +125,14 @@ public final class Context {
      * @param str  text to write
      * @param crlf write a carriage return/new line after text
      */
+    @SuppressWarnings("resource")
     public static void err(final String str, final boolean crlf) {
-        try (final PrintWriter err = Context.getContext().getErr()) {
-            if (err != null) {
-                if (crlf) {
-                    err.println(str);
-                } else {
-                    err.print(str);
-                }
+        final PrintWriter err = Context.getContext().getErr();
+        if (err != null) {
+            if (crlf) {
+                err.println(str);
             } else {
-                if (crlf) {
-                    System.err.println(str);
-                } else {
-                    System.err.println();
-                }
+                err.print(str);
             }
         }
     }
@@ -680,13 +680,11 @@ public final class Context {
      * Hook to print stack trace for a {@link Throwable} that occurred during
      * execution
      *
-     * TODO: use Context.err
-     * .
      * @param t throwable for which to dump stack
      */
     public static void printStackTrace(final Throwable t) {
         if (Context.DEBUG) {
-            t.printStackTrace();
+            t.printStackTrace(Context.getContext().getErr());
         }
     }
 

src/jdk/nashorn/internal/runtime/DebugLogger.java

@@ -59,8 +59,12 @@ public class DebugLogger {
      * @param property   system property activating the logger on {@code info} level
      */
     public DebugLogger(final String loggerName, final String property) {
-        this.logger    = Logging.getLogger(loggerName);
-        this.isEnabled = logger.getLevel() != Level.OFF || (property != null && Options.getBooleanProperty(property));
+        if (property != null && Options.getBooleanProperty(property)) {
+            this.logger = Logging.getOrCreateLogger(loggerName, Level.INFO);
+        } else {
+            this.logger = Logging.getLogger(loggerName);
+        }
+        this.isEnabled = logger.getLevel() != Level.OFF;
     }
 
     /**

src/jdk/nashorn/internal/runtime/ECMAException.java

@@ -181,11 +181,10 @@ public final class ECMAException extends NashornException {
      */
     public static Object printStackTrace(final ScriptObject errObj) {
         final Object exception = getException(errObj);
-        //TODO context err instead of System.err default
         if (exception instanceof Throwable) {
-            ((Throwable)exception).printStackTrace();
+            ((Throwable)exception).printStackTrace(Context.getContext().getErr());
         } else {
-            System.err.println("<stack trace not available>");
+            Context.err("<stack trace not available>");
         }
         return UNDEFINED;
     }

src/jdk/nashorn/internal/runtime/ErrorManager.java

@@ -55,7 +55,7 @@ public class ErrorManager {
      * Constructor
      */
     public ErrorManager() {
-        this(new PrintWriter(System.err, true));
+        this(new PrintWriter(System.err, true)); //bootstrapping, context may not be initialized
     }
 
     /**

src/jdk/nashorn/internal/runtime/Logging.java

@@ -72,25 +72,32 @@ public class Logging {
      * Get a logger for a given class, generating a logger name based on the
      * class name
      *
-     * @param clazz the class
+     * @param name the name to use as key for the logger
      * @return the logger
      */
-    public static Logger getLogger0(final Class<?> clazz) {
-        return Logging.getLogger(Logging.lastPart(clazz.getPackage().getName()));
+    public static Logger getLogger(final String name) {
+        final Logger logger = Logging.loggers.get(name);
+        if (logger != null) {
+            return logger;
+        }
+        return Logging.disabledLogger;
     }
 
     /**
-     * Get a logger for a given name
+     * Get a logger for a given name or create it if not already there, typically
+     * used for mapping system properties to loggers
      *
      * @param name the name to use as key
+     * @param level log lever to reset existing logger with, or create new logger with
      * @return the logger
      */
-    public static Logger getLogger(final String name) {
+    public static Logger getOrCreateLogger(final String name, final Level level) {
         final Logger logger = Logging.loggers.get(name);
-        if (logger != null) {
-            return logger;
+        if (logger == null) {
+            return instantiateLogger(name, level);
         }
-        return Logging.disabledLogger;
+        logger.setLevel(level);
+        return logger;
     }
 
     /**
@@ -114,38 +121,43 @@ public class Logging {
                 }
 
                 final String name = Logging.lastPart(key);
+                final Logger logger = instantiateLogger(name, level);
 
-                final Logger logger = java.util.logging.Logger.getLogger(name);
-                for (final Handler h : logger.getHandlers()) {
-                    logger.removeHandler(h);
-                }
+                Logging.loggers.put(name, logger);
+            }
+        } catch (final IllegalArgumentException | SecurityException e) {
+            throw e;
+        }
+    }
 
-                logger.setLevel(level);
-                logger.setUseParentHandlers(false);
-                final Handler c = new ConsoleHandler();
+    private static Logger instantiateLogger(final String name, final Level level) {
+        final Logger logger = java.util.logging.Logger.getLogger(name);
+        for (final Handler h : logger.getHandlers()) {
+            logger.removeHandler(h);
+        }
 
-                c.setFormatter(new Formatter() {
-                    @Override
-                    public String format(final LogRecord record) {
-                        final StringBuilder sb = new StringBuilder();
+        logger.setLevel(level);
+        logger.setUseParentHandlers(false);
+        final Handler c = new ConsoleHandler();
 
-                        sb.append('[')
-                           .append(record.getLoggerName())
-                           .append("] ")
-                           .append(record.getMessage())
-                           .append('\n');
+        c.setFormatter(new Formatter() {
+            @Override
+            public String format(final LogRecord record) {
+                final StringBuilder sb = new StringBuilder();
 
-                        return sb.toString();
-                    }
-                });
-                logger.addHandler(c);
-                c.setLevel(level);
+                sb.append('[')
+                   .append(record.getLoggerName())
+                   .append("] ")
+                   .append(record.getMessage())
+                   .append('\n');
 
-                Logging.loggers.put(name, logger);
+                return sb.toString();
             }
-        } catch (final IllegalArgumentException | SecurityException e) {
-            throw e;
-        }
+        });
+        logger.addHandler(c);
+        c.setLevel(level);
+
+        return logger;
     }
 
 }

src/jdk/nashorn/internal/runtime/linker/LinkerCallSite.java

@@ -29,8 +29,7 @@ import static jdk.nashorn.internal.runtime.linker.Lookup.MH;
 
 import java.io.FileNotFoundException;
 import java.io.FileOutputStream;
-import java.io.OutputStream;
-import java.io.PrintStream;
+import java.io.PrintWriter;
 import java.lang.invoke.MethodHandle;
 import java.lang.invoke.MethodHandles;
 import java.lang.invoke.MethodType;
@@ -275,26 +274,37 @@ public class LinkerCallSite extends ChainedCallSite {
         }
 
         static class ProfileDumper implements Runnable {
+            @SuppressWarnings("resource")
             @Override
             public void run() {
-                OutputStream out;
+                PrintWriter out = null;
+                boolean fileOutput = false;
 
                 try {
-                    out = new FileOutputStream(PROFILEFILE);
-                } catch (final FileNotFoundException e) {
-                    out = new PrintStream(System.err); //TODO abstraction break- why is this hard coded to System.err when everything else uses the context
-                }
+                    try {
+                        out = new PrintWriter(new FileOutputStream(PROFILEFILE));
+                        fileOutput = true;
+                    } catch (final FileNotFoundException e) {
+                        out = Context.getContext().getErr();
+                    }
 
-                try (PrintStream stream = new PrintStream(out)) {
-                    int index = 0;
-                    for (final ProfilingLinkerCallSite callSite : profileCallSites) {
-                       stream.println("" + (index++) + '\t' +
-                                      callSite.getDescriptor().getName() + '\t' +
-                                      callSite.totalTime + '\t' +
-                                      callSite.hitCount);
+                    dump(out);
+                } finally {
+                    if (out != null && fileOutput) {
+                        out.close();
                     }
                 }
             }
+
+            private static void dump(final PrintWriter out) {
+                int index = 0;
+                for (final ProfilingLinkerCallSite callSite : profileCallSites) {
+                   out.println("" + (index++) + '\t' +
+                                  callSite.getDescriptor().getName() + '\t' +
+                                  callSite.totalTime + '\t' +
+                                  callSite.hitCount);
+                }
+            }
         }
     }
 
@@ -307,11 +317,7 @@ public class LinkerCallSite extends ChainedCallSite {
         private static final MethodHandle TRACEVOID   = findOwnMH("traceVoid", void.class, MethodHandle.class, Object[].class);
         private static final MethodHandle TRACEMISS   = findOwnMH("traceMiss", void.class, Object[].class);
 
-        private static final PrintStream out = System.err; //TODO abstraction break- why is this hard coded to System.err when everything else uses the context
-
-        /*
-         * Constructor
-         */
+        private static final PrintWriter out = Context.getContext().getErr();
 
         TracingLinkerCallSite(final NashornCallSiteDescriptor desc) {
            super(desc);
@@ -522,7 +528,7 @@ public class LinkerCallSite extends ChainedCallSite {
      * Dump the miss counts collected so far to a given output stream
      * @param out print stream
      */
-    public static void getMissCounts(final PrintStream out) {
+    public static void getMissCounts(final PrintWriter out) {
         final ArrayList<Entry<String, AtomicInteger>> entries = new ArrayList<>(missCounts.entrySet());
 
         Collections.sort(entries, new Comparator<Map.Entry<String, AtomicInteger>>() {

src/jdk/nashorn/internal/runtime/linker/MethodHandleFactory.java

@@ -25,6 +25,13 @@
 
 package jdk.nashorn.internal.runtime.linker;
 
+import jdk.nashorn.internal.runtime.ConsString;
+import jdk.nashorn.internal.runtime.Debug;
+import jdk.nashorn.internal.runtime.DebugLogger;
+import jdk.nashorn.internal.runtime.ScriptObject;
+import jdk.nashorn.internal.runtime.options.Options;
+
+import java.io.ByteArrayOutputStream;
 import java.io.PrintStream;
 import java.lang.invoke.MethodHandle;
 import java.lang.invoke.MethodHandles;
@@ -35,29 +42,23 @@ import java.util.ArrayList;
 import java.util.Arrays;
 import java.util.List;
 import java.util.logging.Level;
-import jdk.nashorn.internal.runtime.ConsString;
-import jdk.nashorn.internal.runtime.Debug;
-import jdk.nashorn.internal.runtime.DebugLogger;
-import jdk.nashorn.internal.runtime.ScriptObject;
-import jdk.nashorn.internal.runtime.options.Options;
 
 /**
  * This class is abstraction for all method handle, switchpoint and method type
  * operations. This enables the functionality interface to be subclassed and
- * instrumented, as it has been proven vital to keep the number of method
+ * intrumensted, as it has been proven vital to keep the number of method
  * handles in the system down.
- * <p>
+ *
  * All operations of the above type should go through this class, and not
  * directly into java.lang.invoke
+ *
  */
 public final class MethodHandleFactory {
 
     private static final MethodHandles.Lookup PUBLIC_LOOKUP = MethodHandles.publicLookup();
     private static final MethodHandles.Lookup LOOKUP        = MethodHandles.lookup();
 
-    private static PrintStream ERR = System.err;
-
-    private static final Level TRACE_LEVEL = Level.FINEST;
+    private static final Level TRACE_LEVEL = Level.INFO;
 
     private MethodHandleFactory() {
     }
@@ -97,15 +98,26 @@ public final class MethodHandleFactory {
     }
 
     private static final MethodHandleFunctionality STANDARD = new StandardMethodHandleFunctionality();
-    private static final MethodHandleFunctionality FUNC     =
-        Options.getBooleanProperty("nashorn.methodhandles.debug") ?
-            (Options.getStringProperty("nashorn.methodhandles.debug","").equals("create") ?
-                new TraceCreateMethodHandleFunctionality() :
-                new TraceMethodHandleFunctionality())
-            : STANDARD;
+    private static final MethodHandleFunctionality FUNC;
+
+    private static final String DEBUG_PROPERTY = "nashorn.methodhandles.debug";
+    private static final DebugLogger LOG = new DebugLogger("methodhandles", DEBUG_PROPERTY);
+
+    static {
+        if (LOG.isEnabled() || Options.getBooleanProperty(DEBUG_PROPERTY)) {
+            if (Options.getStringProperty(DEBUG_PROPERTY, "").equals("create")) {
+                FUNC = new TraceCreateMethodHandleFunctionality();
+            } else {
+                FUNC = new TraceMethodHandleFunctionality();
+            }
+        } else {
+            FUNC  = STANDARD;
+        }
+    }
 
     private static final boolean PRINT_STACKTRACE = Options.getBooleanProperty("nashorn.methodhandles.debug.stacktrace");
 
+
     /**
      * Return the method handle functionality used for all method handle operations
      * @return a method handle functionality implementation
@@ -126,11 +138,7 @@ public final class MethodHandleFactory {
      */
     static Object traceReturn(final DebugLogger logger, final Object value) {
         final String str = "\treturn: " + stripName(value) + " [type=" + (value == null ? "null" : stripName(value.getClass()) + ']');
-        if (logger != null) {
-            logger.log(str, TRACE_LEVEL);
-        } else {
-            ERR.println(str);
-        }
+        logger.log(str, TRACE_LEVEL);
         return value;
     }
 
@@ -165,14 +173,19 @@ public final class MethodHandleFactory {
             }
         }
 
-        if (logger != null) {
-            logger.log(sb.toString(), TRACE_LEVEL);
-        } else {
-            ERR.print(sb);
-            if (PRINT_STACKTRACE) {
-                new Throwable().printStackTrace(ERR);
-            }
+        assert logger != null;
+        logger.log(sb.toString(), TRACE_LEVEL);
+        stacktrace(logger);
+    }
+
+    private static void stacktrace(final DebugLogger logger) {
+        if (!PRINT_STACKTRACE) {
+            return;
         }
+        final ByteArrayOutputStream baos = new ByteArrayOutputStream();
+        final PrintStream ps = new PrintStream(baos);
+        new Throwable().printStackTrace(ps);
+        logger.log(baos.toString(), TRACE_LEVEL);
     }
 
     private static String argString(final Object arg) {
@@ -198,18 +211,6 @@ public final class MethodHandleFactory {
         return arg.toString();
     }
 
-    /**
-     * Add a debug printout to a method handle, tracing parameters and return values. Output
-     * will be written to stderr.
-     *
-     * @param mh  method handle to trace
-     * @param tag start of trace message
-     * @return traced method handle
-     */
-    public static MethodHandle addDebugPrintout0(final MethodHandle mh, final Object tag) {
-        return addDebugPrintout(null, mh, 0, true, tag);
-    }
-
     /**
      * Add a debug printout to a method handle, tracing parameters and return values
      *
@@ -240,6 +241,7 @@ public final class MethodHandleFactory {
             return mh;
         }
 
+        assert logger != null;
         assert TRACE != null;
 
         MethodHandle trace = MethodHandles.insertArguments(TRACE, 0, logger, tag, paramStart);
@@ -263,7 +265,7 @@ public final class MethodHandleFactory {
     }
 
     /**
-     * The standard class that marshals all method handle operations to the java.lang.invoke
+     * The standard class that marshalls all method handle operations to the java.lang.invoke
      * package. This exists only so that it can be subclassed and method handles created from
      * Nashorn made possible to instrument.
      *
@@ -464,7 +466,7 @@ public final class MethodHandleFactory {
         }
 
         public MethodHandle debug(final MethodHandle master, final String str, final Object... args) {
-            return addDebugPrintout(null, master, Integer.MAX_VALUE, false, str + ' ' + describe(args));
+            return addDebugPrintout(LOG, master, Integer.MAX_VALUE, false, str + ' ' + describe(args));
         }
 
         @Override
@@ -602,7 +604,7 @@ public final class MethodHandleFactory {
         @Override
         public SwitchPoint createSwitchPoint() {
             final SwitchPoint sp = super.createSwitchPoint();
-            ERR.println("createSwitchPoint " + sp);
+            LOG.log("createSwitchPoint " + sp, TRACE_LEVEL);
             return sp;
         }
 
@@ -615,7 +617,7 @@ public final class MethodHandleFactory {
         @Override
         public MethodType type(final Class<?> returnType, final Class<?>... paramTypes) {
             final MethodType mt = super.type(returnType, paramTypes);
-            ERR.println("methodType " + returnType + ' ' + Arrays.toString(paramTypes) + ' ' + mt);
+            LOG.log("methodType " + returnType + ' ' + Arrays.toString(paramTypes) + ' ' + mt, TRACE_LEVEL);
             return mt;
         }
     }
@@ -626,7 +628,8 @@ public final class MethodHandleFactory {
     private static class TraceCreateMethodHandleFunctionality extends TraceMethodHandleFunctionality {
         @Override
         public MethodHandle debug(final MethodHandle master, final String str, final Object... args) {
-            ERR.println(str + ' ' + describe(args));
+            LOG.log(str + ' ' + describe(args), TRACE_LEVEL);
+            stacktrace(LOG);
             return master;
         }
     }

src/jdk/nashorn/internal/runtime/options/Options.java

@@ -44,19 +44,19 @@ import java.util.StringTokenizer;
 import java.util.TimeZone;
 import java.util.TreeMap;
 import java.util.TreeSet;
+
 import jdk.nashorn.internal.runtime.Logging;
 import jdk.nashorn.internal.runtime.QuotedStringTokenizer;
 
 /**
  * Manages global runtime options.
- *
  */
 public final class Options {
     /** Resource tag. */
     private final String resource;
 
     /** Error writer. */
-    private final PrintWriter errors;
+    private final PrintWriter err;
 
     /** File list. */
     private final List<String> files;
@@ -68,14 +68,25 @@ public final class Options {
     private final TreeMap<String, Option<?>> options;
 
     /**
-     * Constructor.
+     * Constructor
+     *
+     * Options will use System.err as the output stream for any errors
      *
      * @param resource resource prefix for options e.g. "nashorn"
-     * @param errors   error stream for reporting parse errors
      */
-    public Options(final String resource, final PrintWriter errors) {
+    public Options(final String resource) {
+        this(resource, new PrintWriter(System.err, true));
+    }
+
+    /**
+     * Constructor
+     *
+     * @param resource resource prefix for options e.g. "nashorn"
+     * @param err      error stream for reporting parse errors
+     */
+    public Options(final String resource, final PrintWriter err) {
         this.resource  = resource;
-        this.errors    = errors;
+        this.err       = err;
         this.files     = new ArrayList<>();
         this.arguments = new ArrayList<>();
         this.options   = new TreeMap<>();
@@ -88,21 +99,12 @@ public final class Options {
                 if (v != null) {
                     set(t.getKey(), createOption(t, v));
                 } else if (t.getDefaultValue() != null) {
-                     set(t.getKey(), createOption(t, t.getDefaultValue()));
+                    set(t.getKey(), createOption(t, t.getDefaultValue()));
                  }
             }
         }
     }
 
-    /**
-     * Constructor
-     *
-     * @param resource  e.g. "nashorn"
-     */
-    public Options(final String resource) {
-        this(resource, new PrintWriter(System.err, true));
-    }
-
     /**
      * Get the resource for this Options set, e.g. "nashorn"
      * @return the resource
@@ -343,17 +345,17 @@ public final class Options {
                 // display extended help information
                 displayHelp(true);
             } else {
-                errors.println(((IllegalOptionException)e).getTemplate());
+                err.println(((IllegalOptionException)e).getTemplate());
             }
             return;
         }
 
         if (e != null && e.getMessage() != null) {
-            errors.println(getMsg("option.error.invalid.option",
+            err.println(getMsg("option.error.invalid.option",
                     e.getMessage(),
                     helpOptionTemplate.getShortName(),
                     helpOptionTemplate.getName()));
-            errors.println();
+            err.println();
             return;
         }
 
@@ -368,8 +370,8 @@ public final class Options {
     public void displayHelp(final boolean extended) {
         for (final OptionTemplate t : Options.validOptions) {
             if ((extended || !t.isUndocumented()) && t.getResource().equals(resource)) {
-                errors.println(t);
-                errors.println();
+                err.println(t);
+                err.println();
             }
         }
     }

src/jdk/nashorn/tools/Shell.java

@@ -114,7 +114,7 @@ public class Shell {
         try {
             System.exit(main(System.in, System.out, System.err, args));
         } catch (final IOException e) {
-            System.err.println(e);
+            System.err.println(e); //bootstrapping, Context.err may not exist
             System.exit(IO_ERROR);
         }
     }