jaroslav@682: /*
jaroslav@682:  * Copyright (c) 1994, 2010, Oracle and/or its affiliates. All rights reserved.
jaroslav@682:  * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
jaroslav@682:  *
jaroslav@682:  * This code is free software; you can redistribute it and/or modify it
jaroslav@682:  * under the terms of the GNU General Public License version 2 only, as
jaroslav@682:  * published by the Free Software Foundation.  Oracle designates this
jaroslav@682:  * particular file as subject to the "Classpath" exception as provided
jaroslav@682:  * by Oracle in the LICENSE file that accompanied this code.
jaroslav@682:  *
jaroslav@682:  * This code is distributed in the hope that it will be useful, but WITHOUT
jaroslav@682:  * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
jaroslav@682:  * FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License
jaroslav@682:  * version 2 for more details (a copy is included in the LICENSE file that
jaroslav@682:  * accompanied this code).
jaroslav@682:  *
jaroslav@682:  * You should have received a copy of the GNU General Public License version
jaroslav@682:  * 2 along with this work; if not, write to the Free Software Foundation,
jaroslav@682:  * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA.
jaroslav@682:  *
jaroslav@682:  * Please contact Oracle, 500 Oracle Parkway, Redwood Shores, CA 94065 USA
jaroslav@682:  * or visit www.oracle.com if you need additional information or have any
jaroslav@682:  * questions.
jaroslav@682:  */
jaroslav@682: 
jaroslav@682: package java.io;
jaroslav@682: 
jaroslav@682: import java.util.Arrays;
jaroslav@682: 
jaroslav@682: /**
jaroslav@682:  * This class implements an output stream in which the data is
jaroslav@682:  * written into a byte array. The buffer automatically grows as data
jaroslav@682:  * is written to it.
jaroslav@682:  * The data can be retrieved using <code>toByteArray()</code> and
jaroslav@682:  * <code>toString()</code>.
jaroslav@682:  * <p>
jaroslav@682:  * Closing a <tt>ByteArrayOutputStream</tt> has no effect. The methods in
jaroslav@682:  * this class can be called after the stream has been closed without
jaroslav@682:  * generating an <tt>IOException</tt>.
jaroslav@682:  *
jaroslav@682:  * @author  Arthur van Hoff
jaroslav@682:  * @since   JDK1.0
jaroslav@682:  */
jaroslav@682: 
jaroslav@682: public class ByteArrayOutputStream extends OutputStream {
jaroslav@682: 
jaroslav@682:     /**
jaroslav@682:      * The buffer where data is stored.
jaroslav@682:      */
jaroslav@682:     protected byte buf[];
jaroslav@682: 
jaroslav@682:     /**
jaroslav@682:      * The number of valid bytes in the buffer.
jaroslav@682:      */
jaroslav@682:     protected int count;
jaroslav@682: 
jaroslav@682:     /**
jaroslav@682:      * Creates a new byte array output stream. The buffer capacity is
jaroslav@682:      * initially 32 bytes, though its size increases if necessary.
jaroslav@682:      */
jaroslav@682:     public ByteArrayOutputStream() {
jaroslav@682:         this(32);
jaroslav@682:     }
jaroslav@682: 
jaroslav@682:     /**
jaroslav@682:      * Creates a new byte array output stream, with a buffer capacity of
jaroslav@682:      * the specified size, in bytes.
jaroslav@682:      *
jaroslav@682:      * @param   size   the initial size.
jaroslav@682:      * @exception  IllegalArgumentException if size is negative.
jaroslav@682:      */
jaroslav@682:     public ByteArrayOutputStream(int size) {
jaroslav@682:         if (size < 0) {
jaroslav@682:             throw new IllegalArgumentException("Negative initial size: "
jaroslav@682:                                                + size);
jaroslav@682:         }
jaroslav@682:         buf = new byte[size];
jaroslav@682:     }
jaroslav@682: 
jaroslav@682:     /**
jaroslav@682:      * Increases the capacity if necessary to ensure that it can hold
jaroslav@682:      * at least the number of elements specified by the minimum
jaroslav@682:      * capacity argument.
jaroslav@682:      *
jaroslav@682:      * @param minCapacity the desired minimum capacity
jaroslav@682:      * @throws OutOfMemoryError if {@code minCapacity < 0}.  This is
jaroslav@682:      * interpreted as a request for the unsatisfiably large capacity
jaroslav@682:      * {@code (long) Integer.MAX_VALUE + (minCapacity - Integer.MAX_VALUE)}.
jaroslav@682:      */
jaroslav@682:     private void ensureCapacity(int minCapacity) {
jaroslav@682:         // overflow-conscious code
jaroslav@682:         if (minCapacity - buf.length > 0)
jaroslav@682:             grow(minCapacity);
jaroslav@682:     }
jaroslav@682: 
jaroslav@682:     /**
jaroslav@682:      * Increases the capacity to ensure that it can hold at least the
jaroslav@682:      * number of elements specified by the minimum capacity argument.
jaroslav@682:      *
jaroslav@682:      * @param minCapacity the desired minimum capacity
jaroslav@682:      */
jaroslav@682:     private void grow(int minCapacity) {
jaroslav@682:         // overflow-conscious code
jaroslav@682:         int oldCapacity = buf.length;
jaroslav@682:         int newCapacity = oldCapacity << 1;
jaroslav@682:         if (newCapacity - minCapacity < 0)
jaroslav@682:             newCapacity = minCapacity;
jaroslav@682:         if (newCapacity < 0) {
jaroslav@682:             if (minCapacity < 0) // overflow
jaroslav@682:                 throw new OutOfMemoryError();
jaroslav@682:             newCapacity = Integer.MAX_VALUE;
jaroslav@682:         }
jaroslav@682:         buf = Arrays.copyOf(buf, newCapacity);
jaroslav@682:     }
jaroslav@682: 
jaroslav@682:     /**
jaroslav@682:      * Writes the specified byte to this byte array output stream.
jaroslav@682:      *
jaroslav@682:      * @param   b   the byte to be written.
jaroslav@682:      */
jaroslav@682:     public synchronized void write(int b) {
jaroslav@682:         ensureCapacity(count + 1);
jaroslav@682:         buf[count] = (byte) b;
jaroslav@682:         count += 1;
jaroslav@682:     }
jaroslav@682: 
jaroslav@682:     /**
jaroslav@682:      * Writes <code>len</code> bytes from the specified byte array
jaroslav@682:      * starting at offset <code>off</code> to this byte array output stream.
jaroslav@682:      *
jaroslav@682:      * @param   b     the data.
jaroslav@682:      * @param   off   the start offset in the data.
jaroslav@682:      * @param   len   the number of bytes to write.
jaroslav@682:      */
jaroslav@682:     public synchronized void write(byte b[], int off, int len) {
jaroslav@682:         if ((off < 0) || (off > b.length) || (len < 0) ||
jaroslav@682:             ((off + len) - b.length > 0)) {
jaroslav@682:             throw new IndexOutOfBoundsException();
jaroslav@682:         }
jaroslav@682:         ensureCapacity(count + len);
jaroslav@682:         System.arraycopy(b, off, buf, count, len);
jaroslav@682:         count += len;
jaroslav@682:     }
jaroslav@682: 
jaroslav@682:     /**
jaroslav@682:      * Writes the complete contents of this byte array output stream to
jaroslav@682:      * the specified output stream argument, as if by calling the output
jaroslav@682:      * stream's write method using <code>out.write(buf, 0, count)</code>.
jaroslav@682:      *
jaroslav@682:      * @param      out   the output stream to which to write the data.
jaroslav@682:      * @exception  IOException  if an I/O error occurs.
jaroslav@682:      */
jaroslav@682:     public synchronized void writeTo(OutputStream out) throws IOException {
jaroslav@682:         out.write(buf, 0, count);
jaroslav@682:     }
jaroslav@682: 
jaroslav@682:     /**
jaroslav@682:      * Resets the <code>count</code> field of this byte array output
jaroslav@682:      * stream to zero, so that all currently accumulated output in the
jaroslav@682:      * output stream is discarded. The output stream can be used again,
jaroslav@682:      * reusing the already allocated buffer space.
jaroslav@682:      *
jaroslav@682:      * @see     java.io.ByteArrayInputStream#count
jaroslav@682:      */
jaroslav@682:     public synchronized void reset() {
jaroslav@682:         count = 0;
jaroslav@682:     }
jaroslav@682: 
jaroslav@682:     /**
jaroslav@682:      * Creates a newly allocated byte array. Its size is the current
jaroslav@682:      * size of this output stream and the valid contents of the buffer
jaroslav@682:      * have been copied into it.
jaroslav@682:      *
jaroslav@682:      * @return  the current contents of this output stream, as a byte array.
jaroslav@682:      * @see     java.io.ByteArrayOutputStream#size()
jaroslav@682:      */
jaroslav@682:     public synchronized byte toByteArray()[] {
jaroslav@682:         return Arrays.copyOf(buf, count);
jaroslav@682:     }
jaroslav@682: 
jaroslav@682:     /**
jaroslav@682:      * Returns the current size of the buffer.
jaroslav@682:      *
jaroslav@682:      * @return  the value of the <code>count</code> field, which is the number
jaroslav@682:      *          of valid bytes in this output stream.
jaroslav@682:      * @see     java.io.ByteArrayOutputStream#count
jaroslav@682:      */
jaroslav@682:     public synchronized int size() {
jaroslav@682:         return count;
jaroslav@682:     }
jaroslav@682: 
jaroslav@682:     /**
jaroslav@682:      * Converts the buffer's contents into a string decoding bytes using the
jaroslav@682:      * platform's default character set. The length of the new <tt>String</tt>
jaroslav@682:      * is a function of the character set, and hence may not be equal to the
jaroslav@682:      * size of the buffer.
jaroslav@682:      *
jaroslav@682:      * <p> This method always replaces malformed-input and unmappable-character
jaroslav@682:      * sequences with the default replacement string for the platform's
jaroslav@682:      * default character set. The {@linkplain java.nio.charset.CharsetDecoder}
jaroslav@682:      * class should be used when more control over the decoding process is
jaroslav@682:      * required.
jaroslav@682:      *
jaroslav@682:      * @return String decoded from the buffer's contents.
jaroslav@682:      * @since  JDK1.1
jaroslav@682:      */
jaroslav@682:     public synchronized String toString() {
jaroslav@682:         return new String(buf, 0, count);
jaroslav@682:     }
jaroslav@682: 
jaroslav@682:     /**
jaroslav@682:      * Converts the buffer's contents into a string by decoding the bytes using
jaroslav@682:      * the specified {@link java.nio.charset.Charset charsetName}. The length of
jaroslav@682:      * the new <tt>String</tt> is a function of the charset, and hence may not be
jaroslav@682:      * equal to the length of the byte array.
jaroslav@682:      *
jaroslav@682:      * <p> This method always replaces malformed-input and unmappable-character
jaroslav@682:      * sequences with this charset's default replacement string. The {@link
jaroslav@682:      * java.nio.charset.CharsetDecoder} class should be used when more control
jaroslav@682:      * over the decoding process is required.
jaroslav@682:      *
jaroslav@682:      * @param  charsetName  the name of a supported
jaroslav@682:      *              {@linkplain java.nio.charset.Charset </code>charset<code>}
jaroslav@682:      * @return String decoded from the buffer's contents.
jaroslav@682:      * @exception  UnsupportedEncodingException
jaroslav@682:      *             If the named charset is not supported
jaroslav@682:      * @since   JDK1.1
jaroslav@682:      */
jaroslav@682:     public synchronized String toString(String charsetName)
jaroslav@682:         throws UnsupportedEncodingException
jaroslav@682:     {
jaroslav@682:         return new String(buf, 0, count, charsetName);
jaroslav@682:     }
jaroslav@682: 
jaroslav@682:     /**
jaroslav@682:      * Creates a newly allocated string. Its size is the current size of
jaroslav@682:      * the output stream and the valid contents of the buffer have been
jaroslav@682:      * copied into it. Each character <i>c</i> in the resulting string is
jaroslav@682:      * constructed from the corresponding element <i>b</i> in the byte
jaroslav@682:      * array such that:
jaroslav@682:      * <blockquote><pre>
jaroslav@682:      *     c == (char)(((hibyte &amp; 0xff) &lt;&lt; 8) | (b &amp; 0xff))
jaroslav@682:      * </pre></blockquote>
jaroslav@682:      *
jaroslav@682:      * @deprecated This method does not properly convert bytes into characters.
jaroslav@682:      * As of JDK&nbsp;1.1, the preferred way to do this is via the
jaroslav@682:      * <code>toString(String enc)</code> method, which takes an encoding-name
jaroslav@682:      * argument, or the <code>toString()</code> method, which uses the
jaroslav@682:      * platform's default character encoding.
jaroslav@682:      *
jaroslav@682:      * @param      hibyte    the high byte of each resulting Unicode character.
jaroslav@682:      * @return     the current contents of the output stream, as a string.
jaroslav@682:      * @see        java.io.ByteArrayOutputStream#size()
jaroslav@682:      * @see        java.io.ByteArrayOutputStream#toString(String)
jaroslav@682:      * @see        java.io.ByteArrayOutputStream#toString()
jaroslav@682:      */
jaroslav@682:     @Deprecated
jaroslav@682:     public synchronized String toString(int hibyte) {
jaroslav@682:         return new String(buf, hibyte, 0, count);
jaroslav@682:     }
jaroslav@682: 
jaroslav@682:     /**
jaroslav@682:      * Closing a <tt>ByteArrayOutputStream</tt> has no effect. The methods in
jaroslav@682:      * this class can be called after the stream has been closed without
jaroslav@682:      * generating an <tt>IOException</tt>.
jaroslav@682:      * <p>
jaroslav@682:      *
jaroslav@682:      */
jaroslav@682:     public void close() throws IOException {
jaroslav@682:     }
jaroslav@682: 
jaroslav@682: }