/* * Copyright (c) 1996, 2005, 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.Arrays; /** * This class implements a character buffer that can be used as an Writer. * The buffer automatically grows when data is written to the stream. The data * can be retrieved using toCharArray() and toString(). * <P> * Note: Invoking close() on this class has no effect, and methods * of this class can be called after the stream has closed * without generating an IOException. * * @author Herb Jellinek * @since JDK1.1 */publicclass CharArrayWriter extends Writer { /** * The buffer where data is stored. */ protected char buf[]; /** * The number of chars in the buffer. */ protected int count; /** * Creates a new CharArrayWriter. */ public CharArrayWriter() { this(32); } /** * Creates a new CharArrayWriter with the specified initial size. * * @param initialSize an int specifying the initial buffer size. * @exception IllegalArgumentException if initialSize is negative */ public CharArrayWriter(int initialSize) { if (initialSize < 0) { throw new IllegalArgumentException("Negative initial size: " + initialSize); } buf = new char[initialSize]; } /** * Writes a character to the buffer. */ public void write(int c) { synchronized (lock) { int newcount = count + 1; if (newcount > buf.length) { buf = Arrays.copyOf(buf, Math.max(buf.length << 1, newcount)); } buf[count] = (char)c; count = newcount; } } /** * Writes characters to the buffer. * @param c the data to be written * @param off the start offset in the data * @param len the number of chars that are written */ public void write(char c[], int off, int len) { if ((off < 0) || (off > c.length) || (len < 0) || ((off + len) > c.length) || ((off + len) < 0)) { throw new IndexOutOfBoundsException(); } else if (len == 0) { return; } synchronized (lock) { int newcount = count + len; if (newcount > buf.length) { buf = Arrays.copyOf(buf, Math.max(buf.length << 1, newcount)); } System.arraycopy(c, off, buf, count, len); count = newcount; } } /** * Write a portion of a string to the buffer. * @param str String to be written from * @param off Offset from which to start reading characters * @param len Number of characters to be written */ public void write(String str, int off, int len) { synchronized (lock) { int newcount = count + len; if (newcount > buf.length) { buf = Arrays.copyOf(buf, Math.max(buf.length << 1, newcount)); } str.getChars(off, off + len, buf, count); count = newcount; } } /** * Writes the contents of the buffer to another character stream. * * @param out the output stream to write to * @throws IOException If an I/O error occurs. */ public void writeTo(Writer out) throws IOException { synchronized (lock) { out.write(buf, 0, count); } } /** * Appends the specified character sequence to this writer. * * <p> An invocation of this method of the form <tt>out.append(csq)</tt> * behaves in exactly the same way as the invocation * * <pre> * out.write(csq.toString()) </pre> * * <p> Depending on the specification of <tt>toString</tt> for the * character sequence <tt>csq</tt>, the entire sequence may not be * appended. For instance, invoking the <tt>toString</tt> method of a * character buffer will return a subsequence whose content depends upon * the buffer's position and limit. * * @param csq * The character sequence to append. If <tt>csq</tt> is * <tt>null</tt>, then the four characters <tt>"null"</tt> are * appended to this writer. * * @return This writer * * @since 1.5 */ public CharArrayWriter append(CharSequence csq) { String s = (csq == null ? "null" : csq.toString()); write(s, 0, s.length()); return this; } /** * Appends a subsequence of the specified character sequence to this writer. * * <p> An invocation of this method of the form <tt>out.append(csq, start, * end)</tt> when <tt>csq</tt> is not <tt>null</tt>, behaves in * exactly the same way as the invocation * * <pre> * out.write(csq.subSequence(start, end).toString()) </pre> * * @param csq * The character sequence from which a subsequence will be * appended. If <tt>csq</tt> is <tt>null</tt>, then characters * will be appended as if <tt>csq</tt> contained the four * characters <tt>"null"</tt>. * * @param start * The index of the first character in the subsequence * * @param end * The index of the character following the last character in the * subsequence * * @return This writer * * @throws IndexOutOfBoundsException * If <tt>start</tt> or <tt>end</tt> are negative, <tt>start</tt> * is greater than <tt>end</tt>, or <tt>end</tt> is greater than * <tt>csq.length()</tt> * * @since 1.5 */ public CharArrayWriter append(CharSequence csq, int start, int end) { String s = (csq == null ? "null" : csq).subSequence(start, end).toString(); write(s, 0, s.length()); return this; } /** * Appends the specified character to this writer. * * <p> An invocation of this method of the form <tt>out.append(c)</tt> * behaves in exactly the same way as the invocation * * <pre> * out.write(c) </pre> * * @param c * The 16-bit character to append * * @return This writer * * @since 1.5 */ public CharArrayWriter append(char c) { write(c); return this; } /** * Resets the buffer so that you can use it again without * throwing away the already allocated buffer. */ public void reset() { count = 0; } /** * Returns a copy of the input data. * * @return an array of chars copied from the input data. */ public char toCharArray()[] { synchronized (lock) { return Arrays.copyOf(buf, count); } } /** * Returns the current size of the buffer. * * @return an int representing the current size of the buffer. */ public int size() { return count; } /** * Converts input data to a string. * @return the string. */ public String toString() { synchronized (lock) { return new String(buf, 0, count); } } /** * Flush the stream. */ public void flush() { } /** * Close the stream. This method does not release the buffer, since its * contents might still be required. Note: Invoking this method in this class * will have no effect. */ public void close() { } }
/*
* Copyright (c) 1996, 2005, 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.Arrays;
/**
* This class implements a character buffer that can be used as an Writer.
* The buffer automatically grows when data is written to the stream. The data
* can be retrieved using toCharArray() and toString().
* <P>
* Note: Invoking close() on this class has no effect, and methods
* of this class can be called after the stream has closed
* without generating an IOException.
*
* @author Herb Jellinek
* @since JDK1.1
*/
public
class CharArrayWriter extends Writer {
/**
* The buffer where data is stored.
*/
protected char buf[];
/**
* The number of chars in the buffer.
*/
protected int count;
/**
* Creates a new CharArrayWriter.
*/
public CharArrayWriter() {
this(32);
}
/**
* Creates a new CharArrayWriter with the specified initial size.
*
* @param initialSize an int specifying the initial buffer size.
* @exception IllegalArgumentException if initialSize is negative
*/
public CharArrayWriter(int initialSize) {
if (initialSize < 0) {
throw new IllegalArgumentException("Negative initial size: "
+ initialSize);
}
buf = new char[initialSize];
}
/**
* Writes a character to the buffer.
*/
public void write(int c) {
synchronized (lock) {
int newcount = count + 1;
if (newcount > buf.length) {
buf = Arrays.copyOf(buf, Math.max(buf.length << 1, newcount));
}
buf[count] = (char)c;
count = newcount;
}
}
/**
* Writes characters to the buffer.
* @param c the data to be written
* @param off the start offset in the data
* @param len the number of chars that are written
*/
public void write(char c[], int off, int len) {
if ((off < 0) || (off > c.length) || (len < 0) ||
((off + len) > c.length) || ((off + len) < 0)) {
throw new IndexOutOfBoundsException();
} else if (len == 0) {
return;
}
synchronized (lock) {
int newcount = count + len;
if (newcount > buf.length) {
buf = Arrays.copyOf(buf, Math.max(buf.length << 1, newcount));
}
System.arraycopy(c, off, buf, count, len);
count = newcount;
}
}
/**
* Write a portion of a string to the buffer.
* @param str String to be written from
* @param off Offset from which to start reading characters
* @param len Number of characters to be written
*/
public void write(String str, int off, int len) {
synchronized (lock) {
int newcount = count + len;
if (newcount > buf.length) {
buf = Arrays.copyOf(buf, Math.max(buf.length << 1, newcount));
}
str.getChars(off, off + len, buf, count);
count = newcount;
}
}
/**
* Writes the contents of the buffer to another character stream.
*
* @param out the output stream to write to
* @throws IOException If an I/O error occurs.
*/
public void writeTo(Writer out) throws IOException {
synchronized (lock) {
out.write(buf, 0, count);
}
}
/**
* Appends the specified character sequence to this writer.
*
* <p> An invocation of this method of the form <tt>out.append(csq)</tt>
* behaves in exactly the same way as the invocation
*
* <pre>
* out.write(csq.toString()) </pre>
*
* <p> Depending on the specification of <tt>toString</tt> for the
* character sequence <tt>csq</tt>, the entire sequence may not be
* appended. For instance, invoking the <tt>toString</tt> method of a
* character buffer will return a subsequence whose content depends upon
* the buffer's position and limit.
*
* @param csq
* The character sequence to append. If <tt>csq</tt> is
* <tt>null</tt>, then the four characters <tt>"null"</tt> are
* appended to this writer.
*
* @return This writer
*
* @since 1.5
*/
public CharArrayWriter append(CharSequence csq) {
String s = (csq == null ? "null" : csq.toString());
write(s, 0, s.length());
return this;
}
/**
* Appends a subsequence of the specified character sequence to this writer.
*
* <p> An invocation of this method of the form <tt>out.append(csq, start,
* end)</tt> when <tt>csq</tt> is not <tt>null</tt>, behaves in
* exactly the same way as the invocation
*
* <pre>
* out.write(csq.subSequence(start, end).toString()) </pre>
*
* @param csq
* The character sequence from which a subsequence will be
* appended. If <tt>csq</tt> is <tt>null</tt>, then characters
* will be appended as if <tt>csq</tt> contained the four
* characters <tt>"null"</tt>.
*
* @param start
* The index of the first character in the subsequence
*
* @param end
* The index of the character following the last character in the
* subsequence
*
* @return This writer
*
* @throws IndexOutOfBoundsException
* If <tt>start</tt> or <tt>end</tt> are negative, <tt>start</tt>
* is greater than <tt>end</tt>, or <tt>end</tt> is greater than
* <tt>csq.length()</tt>
*
* @since 1.5
*/
public CharArrayWriter append(CharSequence csq, int start, int end) {
String s = (csq == null ? "null" : csq).subSequence(start, end).toString();
write(s, 0, s.length());
return this;
}
/**
* Appends the specified character to this writer.
*
* <p> An invocation of this method of the form <tt>out.append(c)</tt>
* behaves in exactly the same way as the invocation
*
* <pre>
* out.write(c) </pre>
*
* @param c
* The 16-bit character to append
*
* @return This writer
*
* @since 1.5
*/
public CharArrayWriter append(char c) {
write(c);
return this;
}
/**
* Resets the buffer so that you can use it again without
* throwing away the already allocated buffer.
*/
public void reset() {
count = 0;
}
/**
* Returns a copy of the input data.
*
* @return an array of chars copied from the input data.
*/
public char toCharArray()[] {
synchronized (lock) {
return Arrays.copyOf(buf, count);
}
}
/**
* Returns the current size of the buffer.
*
* @return an int representing the current size of the buffer.
*/
public int size() {
return count;
}
/**
* Converts input data to a string.
* @return the string.
*/
public String toString() {
synchronized (lock) {
return new String(buf, 0, count);
}
}
/**
* Flush the stream.
*/
public void flush() { }
/**
* Close the stream. This method does not release the buffer, since its
* contents might still be required. Note: Invoking this method in this class
* will have no effect.
*/
public void close() { }
}