toByteArray() and
+ * toString().
+ *
+ * Closing a ByteArrayOutputStream has no effect. The methods in
+ * this class can be called after the stream has been closed without
+ * generating an IOException.
+ *
+ * @author Arthur van Hoff
+ * @since JDK1.0
+ */
+
+public class ByteArrayOutputStream extends OutputStream {
+
+ /**
+ * The buffer where data is stored.
+ */
+ protected byte buf[];
+
+ /**
+ * The number of valid bytes in the buffer.
+ */
+ protected int count;
+
+ /**
+ * Creates a new byte array output stream. The buffer capacity is
+ * initially 32 bytes, though its size increases if necessary.
+ */
+ public ByteArrayOutputStream() {
+ this(32);
+ }
+
+ /**
+ * Creates a new byte array output stream, with a buffer capacity of
+ * the specified size, in bytes.
+ *
+ * @param size the initial size.
+ * @exception IllegalArgumentException if size is negative.
+ */
+ public ByteArrayOutputStream(int size) {
+ if (size < 0) {
+ throw new IllegalArgumentException("Negative initial size: "
+ + size);
+ }
+ buf = new byte[size];
+ }
+
+ /**
+ * Increases the capacity if necessary to ensure that it can hold
+ * at least the number of elements specified by the minimum
+ * capacity argument.
+ *
+ * @param minCapacity the desired minimum capacity
+ * @throws OutOfMemoryError if {@code minCapacity < 0}. This is
+ * interpreted as a request for the unsatisfiably large capacity
+ * {@code (long) Integer.MAX_VALUE + (minCapacity - Integer.MAX_VALUE)}.
+ */
+ private void ensureCapacity(int minCapacity) {
+ // overflow-conscious code
+ if (minCapacity - buf.length > 0)
+ grow(minCapacity);
+ }
+
+ /**
+ * Increases the capacity to ensure that it can hold at least the
+ * number of elements specified by the minimum capacity argument.
+ *
+ * @param minCapacity the desired minimum capacity
+ */
+ private void grow(int minCapacity) {
+ // overflow-conscious code
+ int oldCapacity = buf.length;
+ int newCapacity = oldCapacity << 1;
+ if (newCapacity - minCapacity < 0)
+ newCapacity = minCapacity;
+ if (newCapacity < 0) {
+ if (minCapacity < 0) // overflow
+ throw new OutOfMemoryError();
+ newCapacity = Integer.MAX_VALUE;
+ }
+ buf = Arrays.copyOf(buf, newCapacity);
+ }
+
+ /**
+ * Writes the specified byte to this byte array output stream.
+ *
+ * @param b the byte to be written.
+ */
+ public synchronized void write(int b) {
+ ensureCapacity(count + 1);
+ buf[count] = (byte) b;
+ count += 1;
+ }
+
+ /**
+ * Writes len bytes from the specified byte array
+ * starting at offset off to this byte array output stream.
+ *
+ * @param b the data.
+ * @param off the start offset in the data.
+ * @param len the number of bytes to write.
+ */
+ public synchronized void write(byte b[], int off, int len) {
+ if ((off < 0) || (off > b.length) || (len < 0) ||
+ ((off + len) - b.length > 0)) {
+ throw new IndexOutOfBoundsException();
+ }
+ ensureCapacity(count + len);
+ System.arraycopy(b, off, buf, count, len);
+ count += len;
+ }
+
+ /**
+ * Writes the complete contents of this byte array output stream to
+ * the specified output stream argument, as if by calling the output
+ * stream's write method using out.write(buf, 0, count).
+ *
+ * @param out the output stream to which to write the data.
+ * @exception IOException if an I/O error occurs.
+ */
+ public synchronized void writeTo(OutputStream out) throws IOException {
+ out.write(buf, 0, count);
+ }
+
+ /**
+ * Resets the count field of this byte array output
+ * stream to zero, so that all currently accumulated output in the
+ * output stream is discarded. The output stream can be used again,
+ * reusing the already allocated buffer space.
+ *
+ * @see java.io.ByteArrayInputStream#count
+ */
+ public synchronized void reset() {
+ count = 0;
+ }
+
+ /**
+ * Creates a newly allocated byte array. Its size is the current
+ * size of this output stream and the valid contents of the buffer
+ * have been copied into it.
+ *
+ * @return the current contents of this output stream, as a byte array.
+ * @see java.io.ByteArrayOutputStream#size()
+ */
+ public synchronized byte toByteArray()[] {
+ return Arrays.copyOf(buf, count);
+ }
+
+ /**
+ * Returns the current size of the buffer.
+ *
+ * @return the value of the count field, which is the number
+ * of valid bytes in this output stream.
+ * @see java.io.ByteArrayOutputStream#count
+ */
+ public synchronized int size() {
+ return count;
+ }
+
+ /**
+ * Converts the buffer's contents into a string decoding bytes using the
+ * platform's default character set. The length of the new String
+ * is a function of the character set, and hence may not be equal to the
+ * size of the buffer.
+ *
+ *
This method always replaces malformed-input and unmappable-character + * sequences with the default replacement string for the platform's + * default character set. The {@linkplain java.nio.charset.CharsetDecoder} + * class should be used when more control over the decoding process is + * required. + * + * @return String decoded from the buffer's contents. + * @since JDK1.1 + */ + public synchronized String toString() { + return new String(buf, 0, count); + } + + /** + * Converts the buffer's contents into a string by decoding the bytes using + * the specified {@link java.nio.charset.Charset charsetName}. The length of + * the new String is a function of the charset, and hence may not be + * equal to the length of the byte array. + * + *
This method always replaces malformed-input and unmappable-character
+ * sequences with this charset's default replacement string. The {@link
+ * java.nio.charset.CharsetDecoder} class should be used when more control
+ * over the decoding process is required.
+ *
+ * @param charsetName the name of a supported
+ * {@linkplain java.nio.charset.Charset charset
+ *
+ */
+ public void close() throws IOException {
+ }
+
+}
}
+ * @return String decoded from the buffer's contents.
+ * @exception UnsupportedEncodingException
+ * If the named charset is not supported
+ * @since JDK1.1
+ */
+ public synchronized String toString(String charsetName)
+ throws UnsupportedEncodingException
+ {
+ return new String(buf, 0, count, charsetName);
+ }
+
+ /**
+ * Creates a newly allocated string. Its size is the current size of
+ * the output stream and the valid contents of the buffer have been
+ * copied into it. Each character c in the resulting string is
+ * constructed from the corresponding element b in the byte
+ * array such that:
+ *
+ *
+ * @deprecated This method does not properly convert bytes into characters.
+ * As of JDK 1.1, the preferred way to do this is via the
+ *
+ * c == (char)(((hibyte & 0xff) << 8) | (b & 0xff))
+ *
toString(String enc) method, which takes an encoding-name
+ * argument, or the toString() method, which uses the
+ * platform's default character encoding.
+ *
+ * @param hibyte the high byte of each resulting Unicode character.
+ * @return the current contents of the output stream, as a string.
+ * @see java.io.ByteArrayOutputStream#size()
+ * @see java.io.ByteArrayOutputStream#toString(String)
+ * @see java.io.ByteArrayOutputStream#toString()
+ */
+ @Deprecated
+ public synchronized String toString(int hibyte) {
+ return new String(buf, hibyte, 0, count);
+ }
+
+ /**
+ * Closing a ByteArrayOutputStream has no effect. The methods in
+ * this class can be called after the stream has been closed without
+ * generating an IOException.
+ *