/*

 * Copyright (c) 1996, 2017, 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.  Oracle designates this

 * particular file as subject to the "Classpath" exception as provided

 * by Oracle in the LICENSE file that accompanied this code.

 *

 * 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.

 */

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;

import java.nio.charset.UnsupportedCharsetException;

/**

 * Prints formatted representations of objects to a text-output stream.  This

 * class implements all of the {@code print} methods found in {@link

 * PrintStream}.  It does not contain methods for writing raw bytes, for which

 * a program should use unencoded byte streams.

 *

 * <p> Unlike the {@link PrintStream} class, if automatic flushing is enabled

 * it will be done only when one of the {@code println}, {@code printf}, or

 * {@code format} methods is invoked, rather than whenever a newline character

 * happens to be output.  These methods use the platform's own notion of line

 * separator rather than the newline character.

 *

 * <p> Methods in this class never throw I/O exceptions, although some of its

 * constructors may.  The client may inquire as to whether any errors have

 * occurred by invoking {@link #checkError checkError()}.

 *

 * <p> This class always replaces malformed and unmappable character sequences with

 * the charset's default replacement string.

 * The {@linkplain java.nio.charset.CharsetEncoder} class should be used when more

 * control over the encoding process is required.

 *

 * @author      Frank Yellin

 * @author      Mark Reinhold

 * @since       1.1

 */

public class PrintWriter extends Writer {

    /**

     * The underlying character-output stream of this

     * {@code PrintWriter}.

     *

     * @since 1.2

     */

    protected Writer out;

    private final boolean autoFlush;

    private boolean trouble = false;

    private Formatter formatter;

    private PrintStream psOut = null;

    /**

     * Returns a charset object for the given charset name.

     * @throws NullPointerException          is csn is null

     * @throws UnsupportedEncodingException  if the charset is not supported

     */

    private static Charset toCharset(String csn)

        throws UnsupportedEncodingException

    {

        Objects.requireNonNull(csn, "charsetName");

        try {

            return Charset.forName(csn);

        } catch (IllegalCharsetNameException|UnsupportedCharsetException unused) {

            // UnsupportedEncodingException should be thrown

            throw new UnsupportedEncodingException(csn);

        }

    }

    /**

     * Creates a new PrintWriter, without automatic line flushing.

     *

     * @param  out        A character-output stream

     */

    public PrintWriter (Writer out) {

        this(out, false);

    }

    /**

     * Creates a new PrintWriter.

     *

     * @param  out        A character-output stream

     * @param  autoFlush  A boolean; if true, the {@code println},

     *                    {@code printf}, or {@code format} methods will

     *                    flush the output buffer

     */

    public PrintWriter(Writer out,

                       boolean autoFlush) {

        super(out);

        this.out = out;

        this.autoFlush = autoFlush;

    }

    /**

     * Creates a new PrintWriter, without automatic line flushing, from an

     * existing OutputStream.  This convenience constructor creates the

     * necessary intermediate OutputStreamWriter, which will convert characters

     * into bytes using the default character encoding.

     *

     * @param  out        An output stream

     *

     * @see java.io.OutputStreamWriter#OutputStreamWriter(java.io.OutputStream)

     */

    public PrintWriter(OutputStream out) {

        this(out, false);

    }

    /**

     * Creates a new PrintWriter from an existing OutputStream.  This

     * convenience constructor creates the necessary intermediate

     * OutputStreamWriter, which will convert characters into bytes using the

     * default character encoding.

     *

     * @param  out        An output stream

     * @param  autoFlush  A boolean; if true, the {@code println},

     *                    {@code printf}, or {@code format} methods will

     *                    flush the output buffer

     *

     * @see java.io.OutputStreamWriter#OutputStreamWriter(java.io.OutputStream)

     */

    public PrintWriter(OutputStream out, boolean autoFlush) {

        this(out, autoFlush, Charset.defaultCharset());

    }

    /**

     * Creates a new PrintWriter from an existing OutputStream.  This

     * convenience constructor creates the necessary intermediate

     * OutputStreamWriter, which will convert characters into bytes using the

     * specified charset.

     *

     * @param  out        An output stream

     * @param  autoFlush  A boolean; if true, the {@code println},

     *                    {@code printf}, or {@code format} methods will

     *                    flush the output buffer

     * @param  charset

     *         A {@linkplain java.nio.charset.Charset charset}

     *

     * @since 10

     */

    public PrintWriter(OutputStream out, boolean autoFlush, Charset charset) {

        this(new BufferedWriter(new OutputStreamWriter(out, charset)), autoFlush);

        // save print stream for error propagation

        if (out instanceof java.io.PrintStream) {

            psOut = (PrintStream) out;

        }

    }

    /**

     * Creates a new PrintWriter, without automatic line flushing, with the

     * specified file name.  This convenience constructor creates the necessary

     * intermediate {@link java.io.OutputStreamWriter OutputStreamWriter},

     * which will encode characters using the {@linkplain

     * java.nio.charset.Charset#defaultCharset() default charset} for this

     * instance of the Java virtual machine.

     *

     * @param  fileName

     *         The name of the file to use as the destination of this writer.

     *         If the file exists then it will be truncated to zero size;

     *         otherwise, a new file will be created.  The output will be

     *         written to the file and is buffered.

     *

     * @throws  FileNotFoundException

     *          If the given string does not denote an existing, writable

     *          regular file and a new regular file of that name cannot be

     *          created, or if some other error occurs while opening or

     *          creating the file

     *

     * @throws  SecurityException

     *          If a security manager is present and {@link

     *          SecurityManager#checkWrite checkWrite(fileName)} denies write

     *          access to the file

     *

     * @since  1.5

     */

    public PrintWriter(String fileName) throws FileNotFoundException {

        this(new BufferedWriter(new OutputStreamWriter(new FileOutputStream(fileName))),

             false);

    }

    /* Private constructor */

    private PrintWriter(Charset charset, File file)

        throws FileNotFoundException

    {

        this(new BufferedWriter(new OutputStreamWriter(new FileOutputStream(file), charset)),

             false);

    }

    /**

     * Creates a new PrintWriter, without automatic line flushing, with the

     * specified file name and charset.  This convenience constructor creates

     * the necessary intermediate {@link java.io.OutputStreamWriter

     * OutputStreamWriter}, which will encode characters using the provided

     * charset.

     *

     * @param  fileName

     *         The name of the file to use as the destination of this writer.

     *         If the file exists then it will be truncated to zero size;

     *         otherwise, a new file will be created.  The output will be

     *         written to the file and is buffered.

     *

     * @param  csn

     *         The name of a supported {@linkplain java.nio.charset.Charset

     *         charset}

     *

     * @throws  FileNotFoundException

     *          If the given string does not denote an existing, writable

     *          regular file and a new regular file of that name cannot be

     *          created, or if some other error occurs while opening or

     *          creating the file

     *

     * @throws  SecurityException

     *          If a security manager is present and {@link

     *          SecurityManager#checkWrite checkWrite(fileName)} denies write

     *          access to the file

     *

     * @throws  UnsupportedEncodingException

     *          If the named charset is not supported

     *

     * @since  1.5

     */

    public PrintWriter(String fileName, String csn)

        throws FileNotFoundException, UnsupportedEncodingException

    {

        this(toCharset(csn), new File(fileName));

    }

    /**

     * Creates a new PrintWriter, without automatic line flushing, with the

     * specified file name and charset.  This convenience constructor creates

     * the necessary intermediate {@link java.io.OutputStreamWriter

     * OutputStreamWriter}, which will encode characters using the provided

     * charset.

     *

     * @param  fileName

     *         The name of the file to use as the destination of this writer.

     *         If the file exists then it will be truncated to zero size;

     *         otherwise, a new file will be created.  The output will be

     *         written to the file and is buffered.

     *

     * @param  charset

     *         A {@linkplain java.nio.charset.Charset charset}

     *

     * @throws  IOException

     *          if an I/O error occurs while opening or creating the file

     *

     * @throws  SecurityException

     *          If a security manager is present and {@link

     *          SecurityManager#checkWrite checkWrite(fileName)} denies write

     *          access to the file

     *

     * @since  10

     */

    public PrintWriter(String fileName, Charset charset) throws IOException {

        this(Objects.requireNonNull(charset, "charset"), new File(fileName));

    }

    /**

     * Creates a new PrintWriter, without automatic line flushing, with the

     * specified file.  This convenience constructor creates the necessary

     * intermediate {@link java.io.OutputStreamWriter OutputStreamWriter},

     * which will encode characters using the {@linkplain

     * java.nio.charset.Charset#defaultCharset() default charset} for this

     * instance of the Java virtual machine.

     *

     * @param  file

     *         The file to use as the destination of this writer.  If the file

     *         exists then it will be truncated to zero size; otherwise, a new

     *         file will be created.  The output will be written to the file

     *         and is buffered.

     *

     * @throws  FileNotFoundException

     *          If the given file object does not denote an existing, writable

     *          regular file and a new regular file of that name cannot be

     *          created, or if some other error occurs while opening or

     *          creating the file

     *

     * @throws  SecurityException

     *          If a security manager is present and {@link

     *          SecurityManager#checkWrite checkWrite(file.getPath())}

     *          denies write access to the file

     *

     * @since  1.5

     */

    public PrintWriter(File file) throws FileNotFoundException {

        this(new BufferedWriter(new OutputStreamWriter(new FileOutputStream(file))),

             false);

    }

    /**

     * Creates a new PrintWriter, without automatic line flushing, with the

     * specified file and charset.  This convenience constructor creates the

     * necessary intermediate {@link java.io.OutputStreamWriter

     * OutputStreamWriter}, which will encode characters using the provided

     * charset.

     *

     * @param  file

     *         The file to use as the destination of this writer.  If the file

     *         exists then it will be truncated to zero size; otherwise, a new

     *         file will be created.  The output will be written to the file

     *         and is buffered.

     *

     * @param  csn

     *         The name of a supported {@linkplain java.nio.charset.Charset

     *         charset}

     *

     * @throws  FileNotFoundException

     *          If the given file object does not denote an existing, writable

     *          regular file and a new regular file of that name cannot be

     *          created, or if some other error occurs while opening or

     *          creating the file

     *

     * @throws  SecurityException

     *          If a security manager is present and {@link

     *          SecurityManager#checkWrite checkWrite(file.getPath())}

     *          denies write access to the file

     *

     * @throws  UnsupportedEncodingException

     *          If the named charset is not supported

     *

     * @since  1.5

     */

    public PrintWriter(File file, String csn)

        throws FileNotFoundException, UnsupportedEncodingException

    {

        this(toCharset(csn), file);

    }

    /**

     * Creates a new PrintWriter, without automatic line flushing, with the

     * specified file and charset.  This convenience constructor creates the

     * necessary intermediate {@link java.io.OutputStreamWriter

     * OutputStreamWriter}, which will encode characters using the provided

     * charset.

     *

     * @param  file

     *         The file to use as the destination of this writer.  If the file

     *         exists then it will be truncated to zero size; otherwise, a new

     *         file will be created.  The output will be written to the file

     *         and is buffered.

     *

     * @param  charset

     *         A {@linkplain java.nio.charset.Charset charset}

     *

     * @throws  IOException

     *          if an I/O error occurs while opening or creating the file

     *

     * @throws  SecurityException

     *          If a security manager is present and {@link

     *          SecurityManager#checkWrite checkWrite(file.getPath())}

     *          denies write access to the file

     *

     * @since  10

     */

    public PrintWriter(File file, Charset charset) throws IOException {

        this(Objects.requireNonNull(charset, "charset"), file);

    }

    /** Checks to make sure that the stream has not been closed */

    private void ensureOpen() throws IOException {

        if (out == null)

            throw new IOException("Stream closed");

    }

    /**

     * Flushes the stream.

     * @see #checkError()

     */

    public void flush() {

        try {

            synchronized (lock) {

                ensureOpen();

                out.flush();

            }

        }

        catch (IOException x) {

            trouble = true;

        }

    }

    /**

     * Closes the stream and releases any system resources associated

     * with it. Closing a previously closed stream has no effect.

     *

     * @see #checkError()

     */

    public void close() {

        try {

            synchronized (lock) {

                if (out == null)

                    return;

                out.close();

                out = null;

            }

        }

        catch (IOException x) {

            trouble = true;

        }

    }

    /**

     * Flushes the stream if it's not closed and checks its error state.

     *

     * @return {@code true} if the print stream has encountered an error,

     *          either on the underlying output stream or during a format

     *          conversion.

     */

    public boolean checkError() {

        if (out != null) {

            flush();

        }

        if (out instanceof java.io.PrintWriter) {

            PrintWriter pw = (PrintWriter) out;

            return pw.checkError();

        } else if (psOut != null) {

            return psOut.checkError();

        }

        return trouble;

    }

    /**

     * Indicates that an error has occurred.

     *

     * <p> This method will cause subsequent invocations of {@link

     * #checkError()} to return {@code true} until {@link

     * #clearError()} is invoked.

     */

    protected void setError() {

        trouble = true;

    }

    /**

     * Clears the error state of this stream.

     *

     * <p> This method will cause subsequent invocations of {@link

     * #checkError()} to return {@code false} until another write

     * operation fails and invokes {@link #setError()}.

     *

     * @since 1.6

     */

    protected void clearError() {

        trouble = false;

    }

    /*

     * Exception-catching, synchronized output operations,

     * which also implement the write() methods of Writer

     */

    /**

     * Writes a single character.

     * @param c int specifying a character to be written.

     */

    public void write(int c) {

        try {

            synchronized (lock) {

                ensureOpen();

                out.write(c);

            }

        }

        catch (InterruptedIOException x) {

            Thread.currentThread().interrupt();

        }

        catch (IOException x) {

            trouble = true;

        }

    }

    /**

     * Writes A Portion of an array of characters.

     * @param buf Array of characters

     * @param off Offset from which to start writing characters

     * @param len Number of characters to write

     *

     * @throws  IndexOutOfBoundsException

     *          If the values of the {@code off} and {@code len} parameters

     *          cause the corresponding method of the underlying {@code Writer}

     *          to throw an {@code IndexOutOfBoundsException}

     */

    public void write(char buf[], int off, int len) {

        try {

            synchronized (lock) {

                ensureOpen();

                out.write(buf, off, len);

            }

        }

        catch (InterruptedIOException x) {

            Thread.currentThread().interrupt();

        }

        catch (IOException x) {

            trouble = true;

        }

    }