--- /dev/null Thu Jan 01 00:00:00 1970 +0000
+++ b/jdk/src/share/classes/java/io/LineNumberReader.java Sat Dec 01 00:00:00 2007 +0000
@@ -0,0 +1,281 @@
+/*
+ * Copyright 1996-2006 Sun Microsystems, Inc. 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. Sun designates this
+ * particular file as subject to the "Classpath" exception as provided
+ * by Sun 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 Sun Microsystems, Inc., 4150 Network Circle, Santa Clara,
+ * CA 95054 USA or visit www.sun.com if you need additional information or
+ * have any questions.
+ */
+
+package java.io;
+
+
+/**
+ * A buffered character-input stream that keeps track of line numbers. This
+ * class defines methods {@link #setLineNumber(int)} and {@link
+ * #getLineNumber()} for setting and getting the current line number
+ * respectively.
+ *
+ * <p> By default, line numbering begins at 0. This number increments at every
+ * <a href="#lt">line terminator</a> as the data is read, and can be changed
+ * with a call to <tt>setLineNumber(int)</tt>. Note however, that
+ * <tt>setLineNumber(int)</tt> does not actually change the current position in
+ * the stream; it only changes the value that will be returned by
+ * <tt>getLineNumber()</tt>.
+ *
+ * <p> A line is considered to be <a name="lt">terminated</a> by any one of a
+ * line feed ('\n'), a carriage return ('\r'), or a carriage return followed
+ * immediately by a linefeed.
+ *
+ * @author Mark Reinhold
+ * @since JDK1.1
+ */
+
+public class LineNumberReader extends BufferedReader {
+
+ /** The current line number */
+ private int lineNumber = 0;
+
+ /** The line number of the mark, if any */
+ private int markedLineNumber; // Defaults to 0
+
+ /** If the next character is a line feed, skip it */
+ private boolean skipLF;
+
+ /** The skipLF flag when the mark was set */
+ private boolean markedSkipLF;
+
+ /**
+ * Create a new line-numbering reader, using the default input-buffer
+ * size.
+ *
+ * @param in
+ * A Reader object to provide the underlying stream
+ */
+ public LineNumberReader(Reader in) {
+ super(in);
+ }
+
+ /**
+ * Create a new line-numbering reader, reading characters into a buffer of
+ * the given size.
+ *
+ * @param in
+ * A Reader object to provide the underlying stream
+ *
+ * @param sz
+ * An int specifying the size of the buffer
+ */
+ public LineNumberReader(Reader in, int sz) {
+ super(in, sz);
+ }
+
+ /**
+ * Set the current line number.
+ *
+ * @param lineNumber
+ * An int specifying the line number
+ *
+ * @see #getLineNumber
+ */
+ public void setLineNumber(int lineNumber) {
+ this.lineNumber = lineNumber;
+ }
+
+ /**
+ * Get the current line number.
+ *
+ * @return The current line number
+ *
+ * @see #setLineNumber
+ */
+ public int getLineNumber() {
+ return lineNumber;
+ }
+
+ /**
+ * Read a single character. <a href="#lt">Line terminators</a> are
+ * compressed into single newline ('\n') characters. Whenever a line
+ * terminator is read the current line number is incremented.
+ *
+ * @return The character read, or -1 if the end of the stream has been
+ * reached
+ *
+ * @throws IOException
+ * If an I/O error occurs
+ */
+ public int read() throws IOException {
+ synchronized (lock) {
+ int c = super.read();
+ if (skipLF) {
+ if (c == '\n')
+ c = super.read();
+ skipLF = false;
+ }
+ switch (c) {
+ case '\r':
+ skipLF = true;
+ case '\n': /* Fall through */
+ lineNumber++;
+ return '\n';
+ }
+ return c;
+ }
+ }
+
+ /**
+ * Read characters into a portion of an array. Whenever a <a
+ * href="#lt">line terminator</a> is read the current line number is
+ * incremented.
+ *
+ * @param cbuf
+ * Destination buffer
+ *
+ * @param off
+ * Offset at which to start storing characters
+ *
+ * @param len
+ * Maximum number of characters to read
+ *
+ * @return The number of bytes read, or -1 if the end of the stream has
+ * already been reached
+ *
+ * @throws IOException
+ * If an I/O error occurs
+ */
+ public int read(char cbuf[], int off, int len) throws IOException {
+ synchronized (lock) {
+ int n = super.read(cbuf, off, len);
+
+ for (int i = off; i < off + n; i++) {
+ int c = cbuf[i];
+ if (skipLF) {
+ skipLF = false;
+ if (c == '\n')
+ continue;
+ }
+ switch (c) {
+ case '\r':
+ skipLF = true;
+ case '\n': /* Fall through */
+ lineNumber++;
+ break;
+ }
+ }
+
+ return n;
+ }
+ }
+
+ /**
+ * Read a line of text. Whenever a <a href="#lt">line terminator</a> is
+ * read the current line number is incremented.
+ *
+ * @return A String containing the contents of the line, not including
+ * any <a href="#lt">line termination characters</a>, or
+ * <tt>null</tt> if the end of the stream has been reached
+ *
+ * @throws IOException
+ * If an I/O error occurs
+ */
+ public String readLine() throws IOException {
+ synchronized (lock) {
+ String l = super.readLine(skipLF);
+ skipLF = false;
+ if (l != null)
+ lineNumber++;
+ return l;
+ }
+ }
+
+ /** Maximum skip-buffer size */
+ private static final int maxSkipBufferSize = 8192;
+
+ /** Skip buffer, null until allocated */
+ private char skipBuffer[] = null;
+
+ /**
+ * Skip characters.
+ *
+ * @param n
+ * The number of characters to skip
+ *
+ * @return The number of characters actually skipped
+ *
+ * @throws IOException
+ * If an I/O error occurs
+ *
+ * @throws IllegalArgumentException
+ * If <tt>n</tt> is negative
+ */
+ public long skip(long n) throws IOException {
+ if (n < 0)
+ throw new IllegalArgumentException("skip() value is negative");
+ int nn = (int) Math.min(n, maxSkipBufferSize);
+ synchronized (lock) {
+ if ((skipBuffer == null) || (skipBuffer.length < nn))
+ skipBuffer = new char[nn];
+ long r = n;
+ while (r > 0) {
+ int nc = read(skipBuffer, 0, (int) Math.min(r, nn));
+ if (nc == -1)
+ break;
+ r -= nc;
+ }
+ return n - r;
+ }
+ }
+
+ /**
+ * Mark the present position in the stream. Subsequent calls to reset()
+ * will attempt to reposition the stream to this point, and will also reset
+ * the line number appropriately.
+ *
+ * @param readAheadLimit
+ * Limit on the number of characters that may be read while still
+ * preserving the mark. After reading this many characters,
+ * attempting to reset the stream may fail.
+ *
+ * @throws IOException
+ * If an I/O error occurs
+ */
+ public void mark(int readAheadLimit) throws IOException {
+ synchronized (lock) {
+ super.mark(readAheadLimit);
+ markedLineNumber = lineNumber;
+ markedSkipLF = skipLF;
+ }
+ }
+
+ /**
+ * Reset the stream to the most recent mark.
+ *
+ * @throws IOException
+ * If the stream has not been marked, or if the mark has been
+ * invalidated
+ */
+ public void reset() throws IOException {
+ synchronized (lock) {
+ super.reset();
+ lineNumber = markedLineNumber;
+ skipLF = markedSkipLF;
+ }
+ }
+
+}