charset}. The charset that it uses
+ * may be specified by name or may be given explicitly, or the platform's
+ * default charset may be accepted.
+ *
+ * Each invocation of a write() method causes the encoding converter to be + * invoked on the given character(s). The resulting bytes are accumulated in a + * buffer before being written to the underlying output stream. The size of + * this buffer may be specified, but by default it is large enough for most + * purposes. Note that the characters passed to the write() methods are not + * buffered. + * + *
For top efficiency, consider wrapping an OutputStreamWriter within a + * BufferedWriter so as to avoid frequent converter invocations. For example: + * + *
+ * Writer out + * = new BufferedWriter(new OutputStreamWriter(System.out)); + *+ * + *
A surrogate pair is a character represented by a sequence of two + * char values: A high surrogate in the range '\uD800' to + * '\uDBFF' followed by a low surrogate in the range '\uDC00' to + * '\uDFFF'. + * + *
A malformed surrogate element is a high surrogate that is not + * followed by a low surrogate or a low surrogate that is not preceded by a + * high surrogate. + * + *
This class always replaces malformed surrogate elements and unmappable
+ * character sequences with the charset's default substitution sequence.
+ * The {@linkplain java.nio.charset.CharsetEncoder} class should be used when more
+ * control over the encoding process is required.
+ *
+ * @see BufferedWriter
+ * @see OutputStream
+ * @see java.nio.charset.Charset
+ *
+ * @author Mark Reinhold
+ * @since JDK1.1
+ */
+
+public class OutputStreamWriter extends Writer {
+
+ private final StreamEncoder se;
+
+ /**
+ * Creates an OutputStreamWriter that uses the named charset.
+ *
+ * @param out
+ * An OutputStream
+ *
+ * @param charsetName
+ * The name of a supported
+ * {@link java.nio.charset.Charset charset}
+ *
+ * @exception UnsupportedEncodingException
+ * If the named encoding is not supported
+ */
+ public OutputStreamWriter(OutputStream out, String charsetName)
+ throws UnsupportedEncodingException
+ {
+ super(out);
+ if (charsetName == null)
+ throw new NullPointerException("charsetName");
+ se = StreamEncoder.forOutputStreamWriter(out, this, charsetName);
+ }
+
+ /**
+ * Creates an OutputStreamWriter that uses the default character encoding.
+ *
+ * @param out An OutputStream
+ */
+ public OutputStreamWriter(OutputStream out) {
+ super(out);
+ try {
+ se = StreamEncoder.forOutputStreamWriter(out, this, (String)null);
+ } catch (UnsupportedEncodingException e) {
+ throw new Error(e);
+ }
+ }
+
+ /**
+ * Creates an OutputStreamWriter that uses the given charset.
If the encoding has an historical name then that name is returned; + * otherwise the encoding's canonical name is returned. + * + *
If this instance was created with the {@link + * #OutputStreamWriter(OutputStream, String)} constructor then the returned + * name, being unique for the encoding, may differ from the name passed to + * the constructor. This method may return null if the stream has + * been closed.
+ * + * @return The historical name of this encoding, or possibly + *null if the stream has been closed
+ *
+ * @see java.nio.charset.Charset
+ *
+ * @revised 1.4
+ * @spec JSR-51
+ */
+ public String getEncoding() {
+ return se.getEncoding();
+ }
+
+ /**
+ * Flushes the output buffer to the underlying byte stream, without flushing
+ * the byte stream itself. This method is non-private only so that it may
+ * be invoked by PrintStream.
+ */
+ void flushBuffer() throws IOException {
+ se.flushBuffer();
+ }
+
+ /**
+ * Writes a single character.
+ *
+ * @exception IOException If an I/O error occurs
+ */
+ public void write(int c) throws IOException {
+ se.write(c);
+ }
+
+ /**
+ * Writes a portion of an array of characters.
+ *
+ * @param cbuf Buffer of characters
+ * @param off Offset from which to start writing characters
+ * @param len Number of characters to write
+ *
+ * @exception IOException If an I/O error occurs
+ */
+ public void write(char cbuf[], int off, int len) throws IOException {
+ se.write(cbuf, off, len);
+ }
+
+ /**
+ * Writes a portion of a string.
+ *
+ * @param str A String
+ * @param off Offset from which to start writing characters
+ * @param len Number of characters to write
+ *
+ * @exception IOException If an I/O error occurs
+ */
+ public void write(String str, int off, int len) throws IOException {
+ se.write(str, off, len);
+ }
+
+ /**
+ * Flushes the stream.
+ *
+ * @exception IOException If an I/O error occurs
+ */
+ public void flush() throws IOException {
+ se.flush();
+ }
+
+ public void close() throws IOException {
+ se.close();
+ }
+}