/*
* 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;
import java.util.Arrays;
/**
* A writable sink for bytes.
*
* <p>Most clients will use output streams that write data to the file system
* ({@link FileOutputStream}), the network ({@link java.net.Socket#getOutputStream()}/{@link
* java.net.HttpURLConnection#getOutputStream()}), or to an in-memory byte array
* ({@link ByteArrayOutputStream}).
*
* <p>Use {@link OutputStreamWriter} to adapt a byte stream like this one into a
* character stream.
*
* <p>Most clients should wrap their output stream with {@link
* BufferedOutputStream}. Callers that do only bulk writes may omit buffering.
*
* <h3>Subclassing OutputStream</h3>
* Subclasses that decorate another output stream should consider subclassing
* {@link FilterOutputStream}, which delegates all calls to the target output
* stream.
*
* <p>All output stream subclasses should override <strong>both</strong> {@link
* #write(int)} and {@link #write(byte[],int,int) write(byte[],int,int)}. The
* three argument overload is necessary for bulk access to the data. This is
* much more efficient than byte-by-byte access.
*
* @see InputStream
*/
public abstract class OutputStream implements Closeable, Flushable {
/**
* Default constructor.
*/
public OutputStream() {
}
/**
* Closes this stream. Implementations of this method should free any
* resources used by the stream. This implementation does nothing.
*
* @throws IOException
* if an error occurs while closing this stream.
*/
public void close() throws IOException {
/* empty */
}
/**
* Flushes this stream. Implementations of this method should ensure that
* any buffered data is written out. This implementation does nothing.
*
* @throws IOException
* if an error occurs while flushing this stream.
*/
public void flush() throws IOException {
/* empty */
}
/**
* Equivalent to {@code write(buffer, 0, buffer.length)}.
*/
public void write(byte[] buffer) throws IOException {
write(buffer, 0, buffer.length);
}
/**
* Writes {@code count} bytes from the byte array {@code buffer} starting at
* position {@code offset} to this stream.
*
* @param buffer
* the buffer to be written.
* @param offset
* the start position in {@code buffer} from where to get bytes.
* @param count
* the number of bytes from {@code buffer} to write to this
* stream.
* @throws IOException
* if an error occurs while writing to this stream.
* @throws IndexOutOfBoundsException
* if {@code offset < 0} or {@code count < 0}, or if
* {@code offset + count} is bigger than the length of
* {@code buffer}.
*/
public void write(byte[] buffer, int offset, int count) throws IOException {
Arrays.checkOffsetAndCount(buffer.length, offset, count);
for (int i = offset; i < offset + count; i++) {
write(buffer[i]);
}
}
/**
* Writes a single byte to this stream. Only the least significant byte of
* the integer {@code oneByte} is written to the stream.
*
* @param oneByte
* the byte to be written.
* @throws IOException
* if an error occurs while writing to this stream.
*/
public abstract void write(int oneByte) throws IOException;
/**
* Returns true if this writer has encountered and suppressed an error. Used
* by PrintStreams as an alternative to checked exceptions.
*/
boolean checkError() {
return false;
}
}