| /* |
| * Copyright (c) 1996, 2016, 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; |
| |
| |
| /** |
| * A character stream that collects its output in a string buffer, which can |
| * then be used to construct a string. |
| * <p> |
| * Closing a {@code StringWriter} has no effect. The methods in this class |
| * can be called after the stream has been closed without generating an |
| * {@code IOException}. |
| * |
| * @author Mark Reinhold |
| * @since 1.1 |
| */ |
| |
| public class StringWriter extends Writer { |
| |
| private StringBuffer buf; |
| |
| /** |
| * Create a new string writer using the default initial string-buffer |
| * size. |
| */ |
| public StringWriter() { |
| buf = new StringBuffer(); |
| lock = buf; |
| } |
| |
| /** |
| * Create a new string writer using the specified initial string-buffer |
| * size. |
| * |
| * @param initialSize |
| * The number of {@code char} values that will fit into this buffer |
| * before it is automatically expanded |
| * |
| * @throws IllegalArgumentException |
| * If {@code initialSize} is negative |
| */ |
| public StringWriter(int initialSize) { |
| if (initialSize < 0) { |
| throw new IllegalArgumentException("Negative buffer size"); |
| } |
| buf = new StringBuffer(initialSize); |
| lock = buf; |
| } |
| |
| /** |
| * Write a single character. |
| */ |
| public void write(int c) { |
| buf.append((char) c); |
| } |
| |
| /** |
| * Write a portion of an array of characters. |
| * |
| * @param cbuf Array of characters |
| * @param off Offset from which to start writing characters |
| * @param len Number of characters to write |
| * |
| * @throws IndexOutOfBoundsException |
| * If {@code off} is negative, or {@code len} is negative, |
| * or {@code off + len} is negative or greater than the length |
| * of the given array |
| */ |
| public void write(char cbuf[], int off, int len) { |
| if ((off < 0) || (off > cbuf.length) || (len < 0) || |
| ((off + len) > cbuf.length) || ((off + len) < 0)) { |
| throw new IndexOutOfBoundsException(); |
| } else if (len == 0) { |
| return; |
| } |
| buf.append(cbuf, off, len); |
| } |
| |
| /** |
| * Write a string. |
| */ |
| public void write(String str) { |
| buf.append(str); |
| } |
| |
| /** |
| * Write a portion of a string. |
| * |
| * @param str String to be written |
| * @param off Offset from which to start writing characters |
| * @param len Number of characters to write |
| * |
| * @throws IndexOutOfBoundsException |
| * If {@code off} is negative, or {@code len} is negative, |
| * or {@code off + len} is negative or greater than the length |
| * of the given string |
| */ |
| public void write(String str, int off, int len) { |
| buf.append(str, off, off + len); |
| } |
| |
| /** |
| * Appends the specified character sequence to this writer. |
| * |
| * <p> An invocation of this method of the form {@code out.append(csq)} |
| * behaves in exactly the same way as the invocation |
| * |
| * <pre> |
| * out.write(csq.toString()) </pre> |
| * |
| * <p> Depending on the specification of {@code toString} for the |
| * character sequence {@code csq}, the entire sequence may not be |
| * appended. For instance, invoking the {@code toString} 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 {@code csq} is |
| * {@code null}, then the four characters {@code "null"} are |
| * appended to this writer. |
| * |
| * @return This writer |
| * |
| * @since 1.5 |
| */ |
| public StringWriter append(CharSequence csq) { |
| write(String.valueOf(csq)); |
| return this; |
| } |
| |
| /** |
| * Appends a subsequence of the specified character sequence to this writer. |
| * |
| * <p> An invocation of this method of the form |
| * {@code out.append(csq, start, end)} when {@code csq} |
| * is not {@code null}, behaves in |
| * exactly the same way as the invocation |
| * |
| * <pre>{@code |
| * out.write(csq.subSequence(start, end).toString()) |
| * }</pre> |
| * |
| * @param csq |
| * The character sequence from which a subsequence will be |
| * appended. If {@code csq} is {@code null}, then characters |
| * will be appended as if {@code csq} contained the four |
| * characters {@code "null"}. |
| * |
| * @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 {@code start} or {@code end} are negative, {@code start} |
| * is greater than {@code end}, or {@code end} is greater than |
| * {@code csq.length()} |
| * |
| * @since 1.5 |
| */ |
| public StringWriter append(CharSequence csq, int start, int end) { |
| if (csq == null) csq = "null"; |
| return append(csq.subSequence(start, end)); |
| } |
| |
| /** |
| * Appends the specified character to this writer. |
| * |
| * <p> An invocation of this method of the form {@code out.append(c)} |
| * 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 StringWriter append(char c) { |
| write(c); |
| return this; |
| } |
| |
| /** |
| * Return the buffer's current value as a string. |
| */ |
| public String toString() { |
| return buf.toString(); |
| } |
| |
| /** |
| * Return the string buffer itself. |
| * |
| * @return StringBuffer holding the current buffer value. |
| */ |
| public StringBuffer getBuffer() { |
| return buf; |
| } |
| |
| /** |
| * Flush the stream. |
| */ |
| public void flush() { |
| } |
| |
| /** |
| * Closing a {@code StringWriter} has no effect. The methods in this |
| * class can be called after the stream has been closed without generating |
| * an {@code IOException}. |
| */ |
| public void close() throws IOException { |
| } |
| |
| } |