| /* |
| * Licensed to the Apache Software Foundation (ASF) under one or more |
| * contributor license agreements. See the NOTICE file distributed with |
| * this work for additional information regarding copyright ownership. |
| * The ASF licenses this file to You under the Apache License, Version 2.0 |
| * (the "License"); you may not use this file except in compliance with |
| * the License. You may obtain a copy of the License at |
| * |
| * http://www.apache.org/licenses/LICENSE-2.0 |
| * |
| * Unless required by applicable law or agreed to in writing, software |
| * distributed under the License is distributed on an "AS IS" BASIS, |
| * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. |
| * See the License for the specific language governing permissions and |
| * limitations under the License. |
| */ |
| |
| package java.io; |
| |
| // BEGIN android-added |
| import org.apache.harmony.luni.util.Msg; |
| // ENd android-added |
| |
| /** |
| * A specialized {@link Writer} that writes characters to a {@code StringBuffer} |
| * in a sequential manner, appending them in the process. The result can later |
| * be queried using the {@link #StringWriter(int)} or {@link #toString()} |
| * methods. |
| * |
| * @see StringReader |
| */ |
| public class StringWriter extends Writer { |
| |
| private StringBuffer buf; |
| |
| /** |
| * Constructs a new {@code StringWriter} which has a {@link StringBuffer} |
| * allocated with the default size of 16 characters. The {@code |
| * StringBuffer} is also the {@code lock} used to synchronize access to this |
| * writer. |
| */ |
| public StringWriter() { |
| super(); |
| buf = new StringBuffer(16); |
| lock = buf; |
| } |
| |
| /** |
| * Constructs a new {@code StringWriter} which has a {@link StringBuffer} |
| * allocated with a size of {@code initialSize} characters. The {@code |
| * StringBuffer} is also the {@code lock} used to synchronize access to this |
| * writer. |
| * |
| * @param initialSize |
| * the intial size of the target string buffer. |
| */ |
| public StringWriter(int initialSize) { |
| if (initialSize < 0) { |
| throw new IllegalArgumentException(); |
| } |
| buf = new StringBuffer(initialSize); |
| lock = buf; |
| } |
| |
| /** |
| * Calling this method has no effect. In contrast to most {@code Writer} subclasses, |
| * the other methods in {@code StringWriter} do not throw an {@code IOException} if |
| * {@code close()} has been called. |
| * |
| * @throws IOException |
| * if an error occurs while closing this writer. |
| */ |
| @Override |
| public void close() throws IOException { |
| /* empty */ |
| } |
| |
| /** |
| * Calling this method has no effect. |
| */ |
| @Override |
| public void flush() { |
| /* empty */ |
| } |
| |
| /** |
| * Gets a reference to this writer's internal {@link StringBuffer}. Any |
| * changes made to the returned buffer are reflected in this writer. |
| * |
| * @return a reference to this writer's internal {@code StringBuffer}. |
| */ |
| public StringBuffer getBuffer() { |
| return buf; |
| } |
| |
| /** |
| * Gets a copy of the contents of this writer as a string. |
| * |
| * @return this writer's contents as a string. |
| */ |
| @Override |
| public String toString() { |
| return buf.toString(); |
| } |
| |
| /** |
| * Writes {@code count} characters starting at {@code offset} in {@code buf} |
| * to this writer's {@code StringBuffer}. |
| * |
| * @param cbuf |
| * the non-null character array to write. |
| * @param offset |
| * the index of the first character in {@code cbuf} to write. |
| * @param count |
| * the maximum number of characters to write. |
| * @throws IndexOutOfBoundsException |
| * if {@code offset < 0} or {@code count < 0}, or if {@code |
| * offset + count} is greater than the size of {@code buf}. |
| */ |
| @Override |
| public void write(char[] cbuf, int offset, int count) { |
| // avoid int overflow |
| // BEGIN android-changed |
| // Exception priorities (in case of multiple errors) differ from |
| // RI, but are spec-compliant. |
| // removed redundant check, added null check, used (offset | count) < 0 |
| // instead of (offset < 0) || (count < 0) to safe one operation |
| if (cbuf == null) { |
| throw new NullPointerException(Msg.getString("K0047")); //$NON-NLS-1$ |
| } |
| if ((offset | count) < 0 || count > cbuf.length - offset) { |
| throw new IndexOutOfBoundsException(Msg.getString("K002f")); //$NON-NLS-1$ |
| } |
| // END android-changed |
| if (count == 0) { |
| return; |
| } |
| buf.append(cbuf, offset, count); |
| } |
| |
| /** |
| * Writes one character to this writer's {@code StringBuffer}. Only the two |
| * least significant bytes of the integer {@code oneChar} are written. |
| * |
| * @param oneChar |
| * the character to write to this writer's {@code StringBuffer}. |
| */ |
| @Override |
| public void write(int oneChar) { |
| buf.append((char) oneChar); |
| } |
| |
| /** |
| * Writes the characters from the specified string to this writer's {@code |
| * StringBuffer}. |
| * |
| * @param str |
| * the non-null string containing the characters to write. |
| */ |
| @Override |
| public void write(String str) { |
| buf.append(str); |
| } |
| |
| /** |
| * Writes {@code count} characters from {@code str} starting at {@code |
| * offset} to this writer's {@code StringBuffer}. |
| * |
| * @param str |
| * the non-null string containing the characters to write. |
| * @param offset |
| * the index of the first character in {@code str} to write. |
| * @param count |
| * the number of characters from {@code str} to write. |
| * @throws StringIndexOutOfBoundsException |
| * if {@code offset < 0} or {@code count < 0}, or if {@code |
| * offset + count} is greater than the length of {@code str}. |
| */ |
| @Override |
| public void write(String str, int offset, int count) { |
| String sub = str.substring(offset, offset + count); |
| buf.append(sub); |
| } |
| |
| /** |
| * Appends the character {@code c} to this writer's {@code StringBuffer}. |
| * This method works the same way as {@link #write(int)}. |
| * |
| * @param c |
| * the character to append to the target stream. |
| * @return this writer. |
| */ |
| @Override |
| public StringWriter append(char c) { |
| write(c); |
| return this; |
| } |
| |
| /** |
| * Appends the character sequence {@code csq} to this writer's {@code |
| * StringBuffer}. This method works the same way as {@code |
| * StringWriter.write(csq.toString())}. If {@code csq} is {@code null}, then |
| * the string "null" is written to the target stream. |
| * |
| * @param csq |
| * the character sequence appended to the target. |
| * @return this writer. |
| */ |
| @Override |
| public StringWriter append(CharSequence csq) { |
| if (null == csq) { |
| write(TOKEN_NULL); |
| } else { |
| write(csq.toString()); |
| } |
| return this; |
| } |
| |
| /** |
| * Appends a subsequence of the character sequence {@code csq} to this |
| * writer's {@code StringBuffer}. This method works the same way as {@code |
| * StringWriter.writer(csq.subsequence(start, end).toString())}. If {@code |
| * csq} is {@code null}, then the specified subsequence of the string "null" |
| * will be written to the target. |
| * |
| * @param csq |
| * the character sequence appended to the target. |
| * @param start |
| * the index of the first char in the character sequence appended |
| * to the target. |
| * @param end |
| * the index of the character following the last character of the |
| * subsequence appended to the target. |
| * @return this writer. |
| * @throws IndexOutOfBoundsException |
| * if {@code start > end}, {@code start < 0}, {@code end < 0} or |
| * either {@code start} or {@code end} are greater or equal than |
| * the length of {@code csq}. |
| */ |
| @Override |
| public StringWriter append(CharSequence csq, int start, int end) { |
| if (null == csq) { |
| csq = TOKEN_NULL; |
| } |
| String output = csq.subSequence(start, end).toString(); |
| write(output, 0, output.length()); |
| return this; |
| } |
| } |