--- old/src/share/classes/java/io/PrintWriter.java	Thu Dec 16 12:05:26 2010
+++ new/src/share/classes/java/io/PrintWriter.java	Thu Dec 16 12:05:25 2010
@@ -25,8 +25,11 @@
 
 package java.io;
 
+import java.util.Objects;
 import java.util.Formatter;
 import java.util.Locale;
+import java.nio.charset.Charset;
+import java.nio.charset.IllegalCharsetNameException;
 
 /**
  * Prints formatted representations of objects to a text-output stream.  This
@@ -59,7 +62,7 @@
      */
     protected Writer out;
 
-    private boolean autoFlush = false;
+    private final boolean autoFlush;
     private boolean trouble = false;
     private Formatter formatter;
     private PrintStream psOut = null;
@@ -68,9 +71,27 @@
      * Line separator string.  This is the value of the line.separator
      * property at the moment that the stream was created.
      */
-    private String lineSeparator;
+    private final String lineSeparator;
 
     /**
+     * Verifies that the given charset is supported.
+     * @throws NullPointerException          is csn is null
+     * @throws UnsupportedEncodingException  if the charset is not supported
+     */
+    private static Void verifyCharsetName(String csn)
+            throws UnsupportedEncodingException {
+        Objects.nonNull(csn, "charsetName");
+        try {
+            if (Charset.isSupported(csn))
+                return null;
+        } catch (IllegalCharsetNameException unused) {
+            /* swallow this exception since UnsupportedEncodingException
+             * will be thrown */
+        }
+        throw new UnsupportedEncodingException(csn);
+    }
+
+    /**
      * Creates a new PrintWriter, without automatic line flushing.
      *
      * @param  out        A character-output stream
@@ -200,8 +221,8 @@
     public PrintWriter(String fileName, String csn)
         throws FileNotFoundException, UnsupportedEncodingException
     {
-        this(new BufferedWriter(new OutputStreamWriter(new FileOutputStream(fileName), csn)),
-             false);
+        this(verifyCharsetName(csn),
+             new BufferedWriter(new OutputStreamWriter(new FileOutputStream(fileName), csn)));
     }
 
     /**
@@ -272,10 +293,20 @@
     public PrintWriter(File file, String csn)
         throws FileNotFoundException, UnsupportedEncodingException
     {
-        this(new BufferedWriter(new OutputStreamWriter(new FileOutputStream(file), csn)),
-             false);
+        this(verifyCharsetName(csn),
+             new BufferedWriter(new OutputStreamWriter(new FileOutputStream(file), csn)));
     }
 
+    /**
+     * Private constructor used by public constructors that accept a
+     * file/filename along with a charset name. This constructor is
+     * necessary so that the charset name can be verified before
+     * creating the FileOutputStream.
+     */
+    private PrintWriter(Void unused, Writer writer) {
+        this(writer, false);
+    }
+
     /** Checks to make sure that the stream has not been closed */
     private void ensureOpen() throws IOException {
         if (out == null)