package com.esotericsoftware.kryo.io;
import java.io.IOException;
import java.io.OutputStream;
import com.esotericsoftware.kryo.KryoException;
/** An OutputStream that buffers data in a byte array and optionally flushes to another OutputStream. Utility methods are provided
* for efficiently writing primitive types and strings.
* @author Nathan Sweet <misc@n4te.com> */
public class Output extends OutputStream {
private int maxCapacity, capacity, position, total;
private byte[] buffer;
private OutputStream outputStream;
/** Creates an uninitialized Output. {@link #setBuffer(byte[], int)} must be called before the Output is used. */
public Output () {
}
/** Creates a new Output for writing to a byte array.
* @param bufferSize The initial and maximum size of the buffer. An exception is thrown if this size is exceeded. */
public Output (int bufferSize) {
this(bufferSize, bufferSize);
}
/** Creates a new Output for writing to a byte array.
* @param bufferSize The initial size of the buffer.
* @param maxBufferSize The buffer is doubled as needed until it exceeds maxBufferSize and an exception is thrown. Can be -1
* for no maximum. */
public Output (int bufferSize, int maxBufferSize) {
if (maxBufferSize < -1) throw new IllegalArgumentException("maxBufferSize cannot be < -1: " + maxBufferSize);
this.capacity = bufferSize;
this.maxCapacity = maxBufferSize == -1 ? Integer.MAX_VALUE : maxBufferSize;
buffer = new byte[bufferSize];
}
/** Creates a new Output for writing to a byte array.
* @see #setBuffer(byte[]) */
public Output (byte[] buffer) {
this(buffer, buffer.length);
}
/** Creates a new Output for writing to a byte array.
* @see #setBuffer(byte[], int) */
public Output (byte[] buffer, int maxBufferSize) {
if (buffer == null) throw new IllegalArgumentException("buffer cannot be null.");
setBuffer(buffer, maxBufferSize);
}
/** Creates a new Output for writing to an OutputStream. A buffer size of 4096 is used. */
public Output (OutputStream outputStream) {
this(4096, 4096);
if (outputStream == null) throw new IllegalArgumentException("outputStream cannot be null.");
this.outputStream = outputStream;
}
/** Creates a new Output for writing to an OutputStream. */
public Output (OutputStream outputStream, int bufferSize) {
this(bufferSize, bufferSize);
if (outputStream == null) throw new IllegalArgumentException("outputStream cannot be null.");
this.outputStream = outputStream;
}
public OutputStream getOutputStream () {
return outputStream;
}
/** Sets a new OutputStream. The position and total are reset, discarding any buffered bytes.
* @param outputStream May be null. */
public void setOutputStream (OutputStream outputStream) {
this.outputStream = outputStream;
position = 0;
total = 0;
}
/** Sets the buffer that will be written to. {@link #setBuffer(byte[], int)} is called with the specified buffer's length as the
* maxBufferSize. */
public void setBuffer (byte[] buffer) {
setBuffer(buffer, buffer.length);
}
/** Sets the buffer that will be written to. The position and total are reset, discarding any buffered bytes. The
* {@link #setOutputStream(OutputStream) OutputStream} is set to null.
* @param maxBufferSize The buffer is doubled as needed until it exceeds maxBufferSize and an exception is thrown. */
public void setBuffer (byte[] buffer, int maxBufferSize) {
if (buffer == null) throw new IllegalArgumentException("buffer cannot be null.");
if (maxBufferSize < -1) throw new IllegalArgumentException("maxBufferSize cannot be < -1: " + maxBufferSize);
this.buffer = buffer;
this.maxCapacity = maxBufferSize == -1 ? Integer.MAX_VALUE : maxBufferSize;
capacity = buffer.length;
position = 0;
total = 0;
outputStream = null;
}
/** Returns the buffer. The bytes between zero and {@link #position()} are the data that has been written. */
public byte[] getBuffer () {
return buffer;
}
/** Returns a new byte array containing the bytes currently in the buffer between zero and {@link #position()}. */
public byte[] toBytes () {
byte[] newBuffer = new byte[position];
System.arraycopy(buffer, 0, newBuffer, 0, position);
return newBuffer;
}
/** Returns the current position in the buffer. This is the number of bytes that have not been flushed. */
public int position () {
return position;
}
/** Sets the current position in the buffer. */
public void setPosition (int position) {
this.position = position;
}
/** Returns the total number of bytes written. This may include bytes that have not been flushed. */
public int total () {
return total + position;
}
/** Sets the position and total to zero. */
public void clear () {
position = 0;
total = 0;
}
/** @return true if the buffer has been resized. */
private boolean require (int required) throws KryoException {
if (capacity - position >= required) return false;
if (required > maxCapacity)
throw new KryoException("Buffer overflow. Max capacity: " + maxCapacity + ", required: " + required);
flush();
while (capacity - position < required) {
if (capacity == maxCapacity)
throw new KryoException("Buffer overflow. Available: " + (capacity - position) + ", required: " + required);
// Grow buffer.
capacity = Math.min(capacity * 2, maxCapacity);
if (capacity < 0) capacity = maxCapacity;
byte[] newBuffer = new byte[capacity];
System.arraycopy(buffer, 0, newBuffer, 0, position);
buffer = newBuffer;
}
return true;
}
// OutputStream
/** Writes the buffered bytes to the underlying OutputStream, if any. */
public void flush () throws KryoException {
if (outputStream == null) return;
try {
outputStream.write(buffer, 0, position);
} catch (IOException ex) {
throw new KryoException(ex);
}
total += position;
position = 0;
}
/** Flushes any buffered bytes and closes the underlying OutputStream, if any. */
public void close () throws KryoException {
flush();
if (outputStream != null) {
try {
outputStream.close();
} catch (IOException ignored) {
}
}
}
/** Writes a byte. */
public void write (int value) throws KryoException {
if (position == capacity) require(1);
buffer[position++] = (byte)value;
}
/** Writes the bytes. Note the byte[] length is not written. */
public void write (byte[] bytes) throws KryoException {
if (bytes == null) throw new IllegalArgumentException("bytes cannot be null.");
writeBytes(bytes, 0, bytes.length);
}
/** Writes the bytes. Note the byte[] length is not written. */
public void write (byte[] bytes, int offset, int length) throws KryoException {
writeBytes(bytes, offset, length);
}
// byte
public void writeByte (byte value) throws KryoException {
if (position == capacity) require(1);
buffer[position++] = value;
}
public void writeByte (int value) throws KryoException {
if (position == capacity) require(1);
buffer[position++] = (byte)value;
}
/** Writes the bytes. Note the byte[] length is not written. */
public void writeBytes (byte[] bytes) throws KryoException {
if (bytes == null) throw new IllegalArgumentException("bytes cannot be null.");
writeBytes(bytes, 0, bytes.length);
}
/** Writes the bytes. Note the byte[] length is not written. */
public void writeBytes (byte[] bytes, int offset, int count) throws KryoException {
if (bytes == null) throw new IllegalArgumentException("bytes cannot be null.");
int copyCount = Math.min(capacity - position, count);
while (true) {
System.arraycopy(bytes, offset, buffer, position, copyCount);
position += copyCount;
count -= copyCount;
if (count == 0) return;
offset += copyCount;
copyCount = Math.min(capacity, count);
require(copyCount);
}
}
// int
/** Writes a 4 byte int. */
public void writeInt (int value) throws KryoException {
require(4);
byte[] buffer = this.buffer;
buffer[position++] = (byte)(value >> 24);
buffer[position++] = (byte)(value >> 16);
buffer[position++] = (byte)(value >> 8);
buffer[position++] = (byte)value;
}
/** Writes a 1-5 byte int.
* @param optimizePositive If true, small positive numbers will be more efficient (1 byte) and small negative numbers will be
* inefficient (5 bytes). */
public int writeInt (int value, boolean optimizePositive) throws KryoException {
if (!optimizePositive) value = (value << 1) ^ (value >> 31);
if (value >>> 7 == 0) {
require(1);
buffer[position++] = (byte)value;
return 1;
}
if (value >>> 14 == 0) {
require(2);
buffer[position++] = (byte)((value & 0x7F) | 0x80);
buffer[position++] = (byte)(value >>> 7);
return 2;
}
if (value >>> 21 == 0) {
require(3);
buffer[position++] = (byte)((value & 0x7F) | 0x80);
buffer[position++] = (byte)(value >>> 7 | 0x80);
buffer[position++] = (byte)(value >>> 14);
return 3;
}
if (value >>> 28 == 0) {
require(4);
buffer[position++] = (byte)((value & 0x7F) | 0x80);
buffer[position++] = (byte)(value >>> 7 | 0x80);
buffer[position++] = (byte)(value >>> 14 | 0x80);
buffer[position++] = (byte)(value >>> 21);
return 4;
}
require(5);
buffer[position++] = (byte)((value & 0x7F) | 0x80);
buffer[position++] = (byte)(value >>> 7 | 0x80);
buffer[position++] = (byte)(value >>> 14 | 0x80);
buffer[position++] = (byte)(value >>> 21 | 0x80);
buffer[position++] = (byte)(value >>> 28);
return 5;
}
// string
/** Writes the length and string, or null. Short strings are checked and if ASCII they are written more efficiently, else they
* are written as UTF8. If a string is known to be ASCII, {@link #writeAscii(String)} may be used. The string can be read using
* {@link Input#readString()} or {@link Input#readStringBuilder()}.
* @param value May be null. */
public void writeString (String value) throws KryoException {
if (value == null) {
writeByte(0x80); // 0 means null, bit 8 means UTF8.
return;
}
int charCount = value.length();
if (charCount == 0) {
writeByte(1 | 0x80); // 1 means empty string, bit 8 means UTF8.
return;
}
// Detect ASCII.
boolean ascii = false;
if (charCount > 1 && charCount < 64) {
ascii = true;
for (int i = 0; i < charCount; i++) {
int c = value.charAt(i);
if (c > 127) {
ascii = false;
break;
}
}
}
if (ascii) {
if (capacity - position < charCount)
writeAscii_slow(value, charCount);
else {
value.getBytes(0, charCount, buffer, position);
position += charCount;
}
buffer[position - 1] |= 0x80;
} else {
writeUtf8Length(charCount + 1);
int charIndex = 0;
if (capacity - position >= charCount) {
// Try to write 8 bit chars.
byte[] buffer = this.buffer;
int position = this.position;
for (; charIndex < charCount; charIndex++) {
int c = value.charAt(charIndex);
if (c > 127) break;
buffer[position++] = (byte)c;
}
this.position = position;
}
if (charIndex < charCount) writeString_slow(value, charCount, charIndex);
}
}
/** Writes the length and CharSequence as UTF8, or null. The string can be read using {@link Input#readString()} or
* {@link Input#readStringBuilder()}.
* @param value May be null. */
public void writeString (CharSequence value) throws KryoException {
if (value == null) {
writeByte(0x80); // 0 means null, bit 8 means UTF8.
return;
}
int charCount = value.length();
if (charCount == 0) {
writeByte(1 | 0x80); // 1 means empty string, bit 8 means UTF8.
return;
}
writeUtf8Length(charCount + 1);
int charIndex = 0;
if (capacity - position >= charCount) {
// Try to write 8 bit chars.
byte[] buffer = this.buffer;
int position = this.position;
for (; charIndex < charCount; charIndex++) {
int c = value.charAt(charIndex);
if (c > 127) break;
buffer[position++] = (byte)c;
}
this.position = position;
}
if (charIndex < charCount) writeString_slow(value, charCount, charIndex);
}
/** Writes a string that is known to contain only ASCII characters. Non-ASCII strings passed to this method will be corrupted.
* Each byte is a 7 bit character with the remaining byte denoting if another character is available. This is slightly more
* efficient than {@link #writeString(String)}. The string can be read using {@link Input#readString()} or
* {@link Input#readStringBuilder()}.
* @param value May be null. */
public void writeAscii (String value) throws KryoException {
if (value == null) {
writeByte(0x80); // 0 means null, bit 8 means UTF8.
return;
}
int charCount = value.length();
if (charCount == 0) {
writeByte(1 | 0x80); // 1 means empty string, bit 8 means UTF8.
return;
}
if (capacity - position < charCount)
writeAscii_slow(value, charCount);
else {
value.getBytes(0, charCount, buffer, position);
position += charCount;
}
buffer[position - 1] |= 0x80; // Bit 8 means end of ASCII.
}
/** Writes the length of a string, which is a variable length encoded int except the first byte uses bit 8 to denote UTF8 and
* bit 7 to denote if another byte is present. */
private void writeUtf8Length (int value) {
if (value >>> 6 == 0) {
require(1);
buffer[position++] = (byte)(value | 0x80); // Set bit 8.
} else if (value >>> 13 == 0) {
require(2);
byte[] buffer = this.buffer;
buffer[position++] = (byte)(value | 0x40 | 0x80); // Set bit 7 and 8.
buffer[position++] = (byte)(value >>> 6);
} else if (value >>> 20 == 0) {
require(3);
byte[] buffer = this.buffer;
buffer[position++] = (byte)(value | 0x40 | 0x80); // Set bit 7 and 8.
buffer[position++] = (byte)((value >>> 6) | 0x80); // Set bit 8.
buffer[position++] = (byte)(value >>> 13);
} else if (value >>> 27 == 0) {
require(4);
byte[] buffer = this.buffer;
buffer[position++] = (byte)(value | 0x40 | 0x80); // Set bit 7 and 8.
buffer[position++] = (byte)((value >>> 6) | 0x80); // Set bit 8.
buffer[position++] = (byte)((value >>> 13) | 0x80); // Set bit 8.
buffer[position++] = (byte)(value >>> 20);
} else {
require(5);
byte[] buffer = this.buffer;
buffer[position++] = (byte)(value | 0x40 | 0x80); // Set bit 7 and 8.
buffer[position++] = (byte)((value >>> 6) | 0x80); // Set bit 8.
buffer[position++] = (byte)((value >>> 13) | 0x80); // Set bit 8.
buffer[position++] = (byte)((value >>> 20) | 0x80); // Set bit 8.
buffer[position++] = (byte)(value >>> 27);
}
}
private void writeString_slow (CharSequence value, int charCount, int charIndex) {
for (; charIndex < charCount; charIndex++) {
if (position == capacity) require(Math.min(capacity, charCount - charIndex));
int c = value.charAt(charIndex);
if (c <= 0x007F) {
buffer[position++] = (byte)c;
} else if (c > 0x07FF) {
buffer[position++] = (byte)(0xE0 | c >> 12 & 0x0F);
require(2);
buffer[position++] = (byte)(0x80 | c >> 6 & 0x3F);
buffer[position++] = (byte)(0x80 | c & 0x3F);
} else {
buffer[position++] = (byte)(0xC0 | c >> 6 & 0x1F);
require(1);
buffer[position++] = (byte)(0x80 | c & 0x3F);
}
}
}
private void writeAscii_slow (String value, int charCount) throws KryoException {
byte[] buffer = this.buffer;
int charIndex = 0;
int charsToWrite = Math.min(charCount, capacity - position);
while (charIndex < charCount) {
value.getBytes(charIndex, charIndex + charsToWrite, buffer, position);
charIndex += charsToWrite;
position += charsToWrite;
charsToWrite = Math.min(charCount - charIndex, capacity);
if (require(charsToWrite)) buffer = this.buffer;
}
}
// float
/** Writes a 4 byte float. */
public void writeFloat (float value) throws KryoException {
writeInt(Float.floatToIntBits(value));
}
/** Writes a 1-5 byte float with reduced precision.
* @param optimizePositive If true, small positive numbers will be more efficient (1 byte) and small negative numbers will be
* inefficient (5 bytes). */
public int writeFloat (float value, float precision, boolean optimizePositive) throws KryoException {
return writeInt((int)(value * precision), optimizePositive);
}
// short
/** Writes a 2 byte short. */
public void writeShort (int value) throws KryoException {
require(2);
buffer[position++] = (byte)(value >>> 8);
buffer[position++] = (byte)value;
}
// long
/** Writes an 8 byte long. */
public void writeLong (long value) throws KryoException {
require(8);
byte[] buffer = this.buffer;
buffer[position++] = (byte)(value >>> 56);
buffer[position++] = (byte)(value >>> 48);
buffer[position++] = (byte)(value >>> 40);
buffer[position++] = (byte)(value >>> 32);
buffer[position++] = (byte)(value >>> 24);
buffer[position++] = (byte)(value >>> 16);
buffer[position++] = (byte)(value >>> 8);
buffer[position++] = (byte)value;
}
/** Writes a 1-9 byte long.
* @param optimizePositive If true, small positive numbers will be more efficient (1 byte) and small negative numbers will be
* inefficient (9 bytes). */
public int writeLong (long value, boolean optimizePositive) throws KryoException {
if (!optimizePositive) value = (value << 1) ^ (value >> 63);
if (value >>> 7 == 0) {
require(1);
buffer[position++] = (byte)value;
return 1;
}
if (value >>> 14 == 0) {
require(2);
buffer[position++] = (byte)((value & 0x7F) | 0x80);
buffer[position++] = (byte)(value >>> 7);
return 2;
}
if (value >>> 21 == 0) {
require(3);
buffer[position++] = (byte)((value & 0x7F) | 0x80);
buffer[position++] = (byte)(value >>> 7 | 0x80);
buffer[position++] = (byte)(value >>> 14);
return 3;
}
if (value >>> 28 == 0) {
require(4);
buffer[position++] = (byte)((value & 0x7F) | 0x80);
buffer[position++] = (byte)(value >>> 7 | 0x80);
buffer[position++] = (byte)(value >>> 14 | 0x80);
buffer[position++] = (byte)(value >>> 21);
return 4;
}
if (value >>> 35 == 0) {
require(5);
buffer[position++] = (byte)((value & 0x7F) | 0x80);
buffer[position++] = (byte)(value >>> 7 | 0x80);
buffer[position++] = (byte)(value >>> 14 | 0x80);
buffer[position++] = (byte)(value >>> 21 | 0x80);
buffer[position++] = (byte)(value >>> 28);
return 5;
}
if (value >>> 42 == 0) {
require(6);
buffer[position++] = (byte)((value & 0x7F) | 0x80);
buffer[position++] = (byte)(value >>> 7 | 0x80);
buffer[position++] = (byte)(value >>> 14 | 0x80);
buffer[position++] = (byte)(value >>> 21 | 0x80);
buffer[position++] = (byte)(value >>> 28 | 0x80);
buffer[position++] = (byte)(value >>> 35);
return 6;
}
if (value >>> 49 == 0) {
require(7);
buffer[position++] = (byte)((value & 0x7F) | 0x80);
buffer[position++] = (byte)(value >>> 7 | 0x80);
buffer[position++] = (byte)(value >>> 14 | 0x80);
buffer[position++] = (byte)(value >>> 21 | 0x80);
buffer[position++] = (byte)(value >>> 28 | 0x80);
buffer[position++] = (byte)(value >>> 35 | 0x80);
buffer[position++] = (byte)(value >>> 42);
return 7;
}
if (value >>> 56 == 0) {
require(8);
buffer[position++] = (byte)((value & 0x7F) | 0x80);
buffer[position++] = (byte)(value >>> 7 | 0x80);
buffer[position++] = (byte)(value >>> 14 | 0x80);
buffer[position++] = (byte)(value >>> 21 | 0x80);
buffer[position++] = (byte)(value >>> 28 | 0x80);
buffer[position++] = (byte)(value >>> 35 | 0x80);
buffer[position++] = (byte)(value >>> 42 | 0x80);
buffer[position++] = (byte)(value >>> 49);
return 8;
}
require(9);
buffer[position++] = (byte)((value & 0x7F) | 0x80);
buffer[position++] = (byte)(value >>> 7 | 0x80);
buffer[position++] = (byte)(value >>> 14 | 0x80);
buffer[position++] = (byte)(value >>> 21 | 0x80);
buffer[position++] = (byte)(value >>> 28 | 0x80);
buffer[position++] = (byte)(value >>> 35 | 0x80);
buffer[position++] = (byte)(value >>> 42 | 0x80);
buffer[position++] = (byte)(value >>> 49 | 0x80);
buffer[position++] = (byte)(value >>> 56);
return 9;
}
// boolean
/** Writes a 1 byte boolean. */
public void writeBoolean (boolean value) throws KryoException {
require(1);
buffer[position++] = (byte)(value ? 1 : 0);
}
// char
/** Writes a 2 byte char. */
public void writeChar (char value) throws KryoException {
require(2);
buffer[position++] = (byte)(value >>> 8);
buffer[position++] = (byte)value;
}
// double
/** Writes an 8 byte double. */
public void writeDouble (double value) throws KryoException {
writeLong(Double.doubleToLongBits(value));
}
/** Writes a 1-9 byte double with reduced precision.
* @param optimizePositive If true, small positive numbers will be more efficient (1 byte) and small negative numbers will be
* inefficient (9 bytes). */
public int writeDouble (double value, double precision, boolean optimizePositive) throws KryoException {
return writeLong((long)(value * precision), optimizePositive);
}
/** Returns the number of bytes that would be written with {@link #writeInt(int, boolean)}. */
static public int intLength (int value, boolean optimizePositive) {
if (!optimizePositive) value = (value << 1) ^ (value >> 31);
if (value >>> 7 == 0) return 1;
if (value >>> 14 == 0) return 2;
if (value >>> 21 == 0) return 3;
if (value >>> 28 == 0) return 4;
return 5;
}
/** Returns the number of bytes that would be written with {@link #writeLong(long, boolean)}. */
static public int longLength (long value, boolean optimizePositive) {
if (!optimizePositive) value = (value << 1) ^ (value >> 63);
if (value >>> 7 == 0) return 1;
if (value >>> 14 == 0) return 2;
if (value >>> 21 == 0) return 3;
if (value >>> 28 == 0) return 4;
if (value >>> 35 == 0) return 5;
if (value >>> 42 == 0) return 6;
if (value >>> 49 == 0) return 7;
if (value >>> 56 == 0) return 8;
return 9;
}
}