// Protocol Buffers - Google's data interchange format
// Copyright 2008 Google Inc. All rights reserved.
// http://code.google.com/p/protobuf/
//
// Redistribution and use in source and binary forms, with or without
// modification, are permitted provided that the following conditions are
// met:
//
// * Redistributions of source code must retain the above copyright
// notice, this list of conditions and the following disclaimer.
// * Redistributions in binary form must reproduce the above
// copyright notice, this list of conditions and the following disclaimer
// in the documentation and/or other materials provided with the
// distribution.
// * Neither the name of Google Inc. nor the names of its
// contributors may be used to endorse or promote products derived from
// this software without specific prior written permission.
//
// THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
// "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
// LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
// A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
// OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
// SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
// LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
// DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
// THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
// (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
// OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
package com.google.protobuf;
import java.io.OutputStream;
import java.io.IOException;
/**
* Encodes and writes protocol message fields.
*
* <p>This class contains two kinds of methods: methods that write specific
* protocol message constructs and field types (e.g. {@link #writeTag} and
* {@link #writeInt32}) and methods that write low-level values (e.g.
* {@link #writeRawVarint32} and {@link #writeRawBytes}). If you are
* writing encoded protocol messages, you should use the former methods, but if
* you are writing some other format of your own design, use the latter.
*
* <p>This class is totally unsynchronized.
*
* @author kneton@google.com Kenton Varda
*/
public final class CodedOutputStream {
private final byte[] buffer;
private final int limit;
private int position;
private final OutputStream output;
/**
* The buffer size used in {@link #newInstance(java.io.OutputStream)}.
*/
public static final int DEFAULT_BUFFER_SIZE = 4096;
private CodedOutputStream(byte[] buffer, int offset, int length) {
this.output = null;
this.buffer = buffer;
this.position = offset;
this.limit = offset + length;
}
private CodedOutputStream(OutputStream output, byte[] buffer) {
this.output = output;
this.buffer = buffer;
this.position = 0;
this.limit = buffer.length;
}
/**
* Create a new {@code CodedOutputStream} wrapping the given
* {@code OutputStream}.
*/
public static CodedOutputStream newInstance(OutputStream output) {
return newInstance(output, DEFAULT_BUFFER_SIZE);
}
/**
* Create a new {@code CodedOutputStream} wrapping the given
* {@code OutputStream} with a given buffer size.
*/
public static CodedOutputStream newInstance(OutputStream output,
int bufferSize) {
return new CodedOutputStream(output, new byte[bufferSize]);
}
/**
* Create a new {@code CodedOutputStream} that writes directly to the given
* byte array. If more bytes are written than fit in the array,
* {@link OutOfSpaceException} will be thrown. Writing directly to a flat
* array is faster than writing to an {@code OutputStream}. See also
* {@link ByteString#newCodedBuilder}.
*/
public static CodedOutputStream newInstance(byte[] flatArray) {
return newInstance(flatArray, 0, flatArray.length);
}
/**
* Create a new {@code CodedOutputStream} that writes directly to the given
* byte array slice. If more bytes are written than fit in the slice,
* {@link OutOfSpaceException} will be thrown. Writing directly to a flat
* array is faster than writing to an {@code OutputStream}. See also
* {@link ByteString#newCodedBuilder}.
*/
public static CodedOutputStream newInstance(byte[] flatArray, int offset,
int length) {
return new CodedOutputStream(flatArray, offset, length);
}
// -----------------------------------------------------------------
/** Write a {@code double} field, including tag, to the stream. */
public void writeDouble(int fieldNumber, double value) throws IOException {
writeTag(fieldNumber, WireFormat.WIRETYPE_FIXED64);
writeRawLittleEndian64(Double.doubleToRawLongBits(value));
}
/** Write a {@code float} field, including tag, to the stream. */
public void writeFloat(int fieldNumber, float value) throws IOException {
writeTag(fieldNumber, WireFormat.WIRETYPE_FIXED32);
writeRawLittleEndian32(Float.floatToRawIntBits(value));
}
/** Write a {@code uint64} field, including tag, to the stream. */
public void writeUInt64(int fieldNumber, long value) throws IOException {
writeTag(fieldNumber, WireFormat.WIRETYPE_VARINT);
writeRawVarint64(value);
}
/** Write an {@code int64} field, including tag, to the stream. */
public void writeInt64(int fieldNumber, long value) throws IOException {
writeTag(fieldNumber, WireFormat.WIRETYPE_VARINT);
writeRawVarint64(value);
}
/** Write an {@code int32} field, including tag, to the stream. */
public void writeInt32(int fieldNumber, int value) throws IOException {
writeTag(fieldNumber, WireFormat.WIRETYPE_VARINT);
if (value >= 0) {
writeRawVarint32(value);
} else {
// Must sign-extend.
writeRawVarint64(value);
}
}
/** Write a {@code fixed64} field, including tag, to the stream. */
public void writeFixed64(int fieldNumber, long value) throws IOException {
writeTag(fieldNumber, WireFormat.WIRETYPE_FIXED64);
writeRawLittleEndian64(value);
}
/** Write a {@code fixed32} field, including tag, to the stream. */
public void writeFixed32(int fieldNumber, int value) throws IOException {
writeTag(fieldNumber, WireFormat.WIRETYPE_FIXED32);
writeRawLittleEndian32(value);
}
/** Write a {@code bool} field, including tag, to the stream. */
public void writeBool(int fieldNumber, boolean value) throws IOException {
writeTag(fieldNumber, WireFormat.WIRETYPE_VARINT);
writeRawByte(value ? 1 : 0);
}
/** Write a {@code string} field, including tag, to the stream. */
public void writeString(int fieldNumber, String value) throws IOException {
writeTag(fieldNumber, WireFormat.WIRETYPE_LENGTH_DELIMITED);
// Unfortunately there does not appear to be any way to tell Java to encode
// UTF-8 directly into our buffer, so we have to let it create its own byte
// array and then copy.
byte[] bytes = value.getBytes("UTF-8");
writeRawVarint32(bytes.length);
writeRawBytes(bytes);
}
/** Write a {@code group} field, including tag, to the stream. */
public void writeGroup(int fieldNumber, Message value) throws IOException {
writeTag(fieldNumber, WireFormat.WIRETYPE_START_GROUP);
value.writeTo(this);
writeTag(fieldNumber, WireFormat.WIRETYPE_END_GROUP);
}
/** Write a group represented by an {@link UnknownFieldSet}. */
public void writeUnknownGroup(int fieldNumber, UnknownFieldSet value)
throws IOException {
writeTag(fieldNumber, WireFormat.WIRETYPE_START_GROUP);
value.writeTo(this);
writeTag(fieldNumber, WireFormat.WIRETYPE_END_GROUP);
}
/** Write an embedded message field, including tag, to the stream. */
public void writeMessage(int fieldNumber, Message value) throws IOException {
writeTag(fieldNumber, WireFormat.WIRETYPE_LENGTH_DELIMITED);
writeRawVarint32(value.getSerializedSize());
value.writeTo(this);
}
/** Write a {@code bytes} field, including tag, to the stream. */
public void writeBytes(int fieldNumber, ByteString value) throws IOException {
writeTag(fieldNumber, WireFormat.WIRETYPE_LENGTH_DELIMITED);
byte[] bytes = value.toByteArray();
writeRawVarint32(bytes.length);
writeRawBytes(bytes);
}
/** Write a {@code uint32} field, including tag, to the stream. */
public void writeUInt32(int fieldNumber, int value) throws IOException {
writeTag(fieldNumber, WireFormat.WIRETYPE_VARINT);
writeRawVarint32(value);
}
/**
* Write an enum field, including tag, to the stream. Caller is responsible
* for converting the enum value to its numeric value.
*/
public void writeEnum(int fieldNumber, int value) throws IOException {
writeTag(fieldNumber, WireFormat.WIRETYPE_VARINT);
writeRawVarint32(value);
}
/** Write an {@code sfixed32} field, including tag, to the stream. */
public void writeSFixed32(int fieldNumber, int value) throws IOException {
writeTag(fieldNumber, WireFormat.WIRETYPE_FIXED32);
writeRawLittleEndian32(value);
}
/** Write an {@code sfixed64} field, including tag, to the stream. */
public void writeSFixed64(int fieldNumber, long value) throws IOException {
writeTag(fieldNumber, WireFormat.WIRETYPE_FIXED64);
writeRawLittleEndian64(value);
}
/** Write an {@code sint32} field, including tag, to the stream. */
public void writeSInt32(int fieldNumber, int value) throws IOException {
writeTag(fieldNumber, WireFormat.WIRETYPE_VARINT);
writeRawVarint32(encodeZigZag32(value));
}
/** Write an {@code sint64} field, including tag, to the stream. */
public void writeSInt64(int fieldNumber, long value) throws IOException {
writeTag(fieldNumber, WireFormat.WIRETYPE_VARINT);
writeRawVarint64(encodeZigZag64(value));
}
/**
* Write a MessageSet extension field to the stream. For historical reasons,
* the wire format differs from normal fields.
*/
public void writeMessageSetExtension(int fieldNumber, Message value)
throws IOException {
writeTag(WireFormat.MESSAGE_SET_ITEM, WireFormat.WIRETYPE_START_GROUP);
writeUInt32(WireFormat.MESSAGE_SET_TYPE_ID, fieldNumber);
writeMessage(WireFormat.MESSAGE_SET_MESSAGE, value);
writeTag(WireFormat.MESSAGE_SET_ITEM, WireFormat.WIRETYPE_END_GROUP);
}
/**
* Write an unparsed MessageSet extension field to the stream. For
* historical reasons, the wire format differs from normal fields.
*/
public void writeRawMessageSetExtension(int fieldNumber, ByteString value)
throws IOException {
writeTag(WireFormat.MESSAGE_SET_ITEM, WireFormat.WIRETYPE_START_GROUP);
writeUInt32(WireFormat.MESSAGE_SET_TYPE_ID, fieldNumber);
writeBytes(WireFormat.MESSAGE_SET_MESSAGE, value);
writeTag(WireFormat.MESSAGE_SET_ITEM, WireFormat.WIRETYPE_END_GROUP);
}
/**
* Write a field of arbitrary type, including tag, to the stream.
*
* @param type The field's type.
* @param number The field's number.
* @param value Object representing the field's value. Must be of the exact
* type which would be returned by
* {@link Message#getField(Descriptors.FieldDescriptor)} for
* this field.
*/
public void writeField(Descriptors.FieldDescriptor.Type type,
int number, Object value) throws IOException {
switch (type) {
case DOUBLE : writeDouble (number, (Double )value); break;
case FLOAT : writeFloat (number, (Float )value); break;
case INT64 : writeInt64 (number, (Long )value); break;
case UINT64 : writeUInt64 (number, (Long )value); break;
case INT32 : writeInt32 (number, (Integer )value); break;
case FIXED64 : writeFixed64 (number, (Long )value); break;
case FIXED32 : writeFixed32 (number, (Integer )value); break;
case BOOL : writeBool (number, (Boolean )value); break;
case STRING : writeString (number, (String )value); break;
case GROUP : writeGroup (number, (Message )value); break;
case MESSAGE : writeMessage (number, (Message )value); break;
case BYTES : writeBytes (number, (ByteString)value); break;
case UINT32 : writeUInt32 (number, (Integer )value); break;
case SFIXED32: writeSFixed32(number, (Integer )value); break;
case SFIXED64: writeSFixed64(number, (Long )value); break;
case SINT32 : writeSInt32 (number, (Integer )value); break;
case SINT64 : writeSInt64 (number, (Long )value); break;
case ENUM:
writeEnum(number, ((Descriptors.EnumValueDescriptor)value).getNumber());
break;
}
}
// =================================================================
/**
* Compute the number of bytes that would be needed to encode a
* {@code double} field, including tag.
*/
public static int computeDoubleSize(int fieldNumber, double value) {
return computeTagSize(fieldNumber) + LITTLE_ENDIAN_64_SIZE;
}
/**
* Compute the number of bytes that would be needed to encode a
* {@code float} field, including tag.
*/
public static int computeFloatSize(int fieldNumber, float value) {
return computeTagSize(fieldNumber) + LITTLE_ENDIAN_32_SIZE;
}
/**
* Compute the number of bytes that would be needed to encode a
* {@code uint64} field, including tag.
*/
public static int computeUInt64Size(int fieldNumber, long value) {
return computeTagSize(fieldNumber) + computeRawVarint64Size(value);
}
/**
* Compute the number of bytes that would be needed to encode an
* {@code int64} field, including tag.
*/
public static int computeInt64Size(int fieldNumber, long value) {
return computeTagSize(fieldNumber) + computeRawVarint64Size(value);
}
/**
* Compute the number of bytes that would be needed to encode an
* {@code int32} field, including tag.
*/
public static int computeInt32Size(int fieldNumber, int value) {
if (value >= 0) {
return computeTagSize(fieldNumber) + computeRawVarint32Size(value);
} else {
// Must sign-extend.
return computeTagSize(fieldNumber) + 10;
}
}
/**
* Compute the number of bytes that would be needed to encode a
* {@code fixed64} field, including tag.
*/
public static int computeFixed64Size(int fieldNumber, long value) {
return computeTagSize(fieldNumber) + LITTLE_ENDIAN_64_SIZE;
}
/**
* Compute the number of bytes that would be needed to encode a
* {@code fixed32} field, including tag.
*/
public static int computeFixed32Size(int fieldNumber, int value) {
return computeTagSize(fieldNumber) + LITTLE_ENDIAN_32_SIZE;
}
/**
* Compute the number of bytes that would be needed to encode a
* {@code bool} field, including tag.
*/
public static int computeBoolSize(int fieldNumber, boolean value) {
return computeTagSize(fieldNumber) + 1;
}
/**
* Compute the number of bytes that would be needed to encode a
* {@code string} field, including tag.
*/
public static int computeStringSize(int fieldNumber, String value) {
try {
byte[] bytes = value.getBytes("UTF-8");
return computeTagSize(fieldNumber) +
computeRawVarint32Size(bytes.length) +
bytes.length;
} catch (java.io.UnsupportedEncodingException e) {
throw new RuntimeException("UTF-8 not supported.", e);
}
}
/**
* Compute the number of bytes that would be needed to encode a
* {@code group} field, including tag.
*/
public static int computeGroupSize(int fieldNumber, Message value) {
return computeTagSize(fieldNumber) * 2 + value.getSerializedSize();
}
/**
* Compute the number of bytes that would be needed to encode a
* {@code group} field represented by an {@code UnknownFieldSet}, including
* tag.
*/
public static int computeUnknownGroupSize(int fieldNumber,
UnknownFieldSet value) {
return computeTagSize(fieldNumber) * 2 + value.getSerializedSize();
}
/**
* Compute the number of bytes that would be needed to encode an
* embedded message field, including tag.
*/
public static int computeMessageSize(int fieldNumber, Message value) {
int size = value.getSerializedSize();
return computeTagSize(fieldNumber) + computeRawVarint32Size(size) + size;
}
/**
* Compute the number of bytes that would be needed to encode a
* {@code bytes} field, including tag.
*/
public static int computeBytesSize(int fieldNumber, ByteString value) {
return computeTagSize(fieldNumber) +
computeRawVarint32Size(value.size()) +
value.size();
}
/**
* Compute the number of bytes that would be needed to encode a
* {@code uint32} field, including tag.
*/
public static int computeUInt32Size(int fieldNumber, int value) {
return computeTagSize(fieldNumber) + computeRawVarint32Size(value);
}
/**
* Compute the number of bytes that would be needed to encode an
* enum field, including tag. Caller is responsible for converting the
* enum value to its numeric value.
*/
public static int computeEnumSize(int fieldNumber, int value) {
return computeTagSize(fieldNumber) + computeRawVarint32Size(value);
}
/**
* Compute the number of bytes that would be needed to encode an
* {@code sfixed32} field, including tag.
*/
public static int computeSFixed32Size(int fieldNumber, int value) {
return computeTagSize(fieldNumber) + LITTLE_ENDIAN_32_SIZE;
}
/**
* Compute the number of bytes that would be needed to encode an
* {@code sfixed64} field, including tag.
*/
public static int computeSFixed64Size(int fieldNumber, long value) {
return computeTagSize(fieldNumber) + LITTLE_ENDIAN_64_SIZE;
}
/**
* Compute the number of bytes that would be needed to encode an
* {@code sint32} field, including tag.
*/
public static int computeSInt32Size(int fieldNumber, int value) {
return computeTagSize(fieldNumber) +
computeRawVarint32Size(encodeZigZag32(value));
}
/**
* Compute the number of bytes that would be needed to encode an
* {@code sint64} field, including tag.
*/
public static int computeSInt64Size(int fieldNumber, long value) {
return computeTagSize(fieldNumber) +
computeRawVarint64Size(encodeZigZag64(value));
}
/**
* Compute the number of bytes that would be needed to encode a
* MessageSet extension to the stream. For historical reasons,
* the wire format differs from normal fields.
*/
public static int computeMessageSetExtensionSize(
int fieldNumber, Message value) {
return computeTagSize(WireFormat.MESSAGE_SET_ITEM) * 2 +
computeUInt32Size(WireFormat.MESSAGE_SET_TYPE_ID, fieldNumber) +
computeMessageSize(WireFormat.MESSAGE_SET_MESSAGE, value);
}
/**
* Compute the number of bytes that would be needed to encode an
* unparsed MessageSet extension field to the stream. For
* historical reasons, the wire format differs from normal fields.
*/
public static int computeRawMessageSetExtensionSize(
int fieldNumber, ByteString value) {
return computeTagSize(WireFormat.MESSAGE_SET_ITEM) * 2 +
computeUInt32Size(WireFormat.MESSAGE_SET_TYPE_ID, fieldNumber) +
computeBytesSize(WireFormat.MESSAGE_SET_MESSAGE, value);
}
/**
* Compute the number of bytes that would be needed to encode a
* field of arbitrary type, including tag, to the stream.
*
* @param type The field's type.
* @param number The field's number.
* @param value Object representing the field's value. Must be of the exact
* type which would be returned by
* {@link Message#getField(Descriptors.FieldDescriptor)} for
* this field.
*/
public static int computeFieldSize(
Descriptors.FieldDescriptor.Type type,
int number, Object value) {
switch (type) {
case DOUBLE : return computeDoubleSize (number, (Double )value);
case FLOAT : return computeFloatSize (number, (Float )value);
case INT64 : return computeInt64Size (number, (Long )value);
case UINT64 : return computeUInt64Size (number, (Long )value);
case INT32 : return computeInt32Size (number, (Integer )value);
case FIXED64 : return computeFixed64Size (number, (Long )value);
case FIXED32 : return computeFixed32Size (number, (Integer )value);
case BOOL : return computeBoolSize (number, (Boolean )value);
case STRING : return computeStringSize (number, (String )value);
case GROUP : return computeGroupSize (number, (Message )value);
case MESSAGE : return computeMessageSize (number, (Message )value);
case BYTES : return computeBytesSize (number, (ByteString)value);
case UINT32 : return computeUInt32Size (number, (Integer )value);
case SFIXED32: return computeSFixed32Size(number, (Integer )value);
case SFIXED64: return computeSFixed64Size(number, (Long )value);
case SINT32 : return computeSInt32Size (number, (Integer )value);
case SINT64 : return computeSInt64Size (number, (Long )value);
case ENUM:
return computeEnumSize(number,
((Descriptors.EnumValueDescriptor)value).getNumber());
}
throw new RuntimeException(
"There is no way to get here, but the compiler thinks otherwise.");
}
// =================================================================
/**
* Internal helper that writes the current buffer to the output. The
* buffer position is reset to its initial value when this returns.
*/
private void refreshBuffer() throws IOException {
if (output == null) {
// We're writing to a single buffer.
throw new OutOfSpaceException();
}
// Since we have an output stream, this is our buffer
// and buffer offset == 0
output.write(buffer, 0, position);
position = 0;
}
/**
* Flushes the stream and forces any buffered bytes to be written. This
* does not flush the underlying OutputStream.
*/
public void flush() throws IOException {
if (output != null) {
refreshBuffer();
}
}
/**
* If writing to a flat array, return the space left in the array.
* Otherwise, throws {@code UnsupportedOperationException}.
*/
public int spaceLeft() {
if (output == null) {
return limit - position;
} else {
throw new UnsupportedOperationException(
"spaceLeft() can only be called on CodedOutputStreams that are " +
"writing to a flat array.");
}
}
/**
* Verifies that {@link #spaceLeft()} returns zero. It's common to create
* a byte array that is exactly big enough to hold a message, then write to
* it with a {@code CodedOutputStream}. Calling {@code checkNoSpaceLeft()}
* after writing verifies that the message was actually as big as expected,
* which can help catch bugs.
*/
public void checkNoSpaceLeft() {
if (spaceLeft() != 0) {
throw new IllegalStateException(
"Did not write as much data as expected.");
}
}
/**
* If you create a CodedOutputStream around a simple flat array, you must
* not attempt to write more bytes than the array has space. Otherwise,
* this exception will be thrown.
*/
public static class OutOfSpaceException extends IOException {
OutOfSpaceException() {
super("CodedOutputStream was writing to a flat byte array and ran " +
"out of space.");
}
}
/** Write a single byte. */
public void writeRawByte(byte value) throws IOException {
if (position == limit) {
refreshBuffer();
}
buffer[position++] = value;
}
/** Write a single byte, represented by an integer value. */
public void writeRawByte(int value) throws IOException {
writeRawByte((byte) value);
}
/** Write an array of bytes. */
public void writeRawBytes(byte[] value) throws IOException {
writeRawBytes(value, 0, value.length);
}
/** Write part of an array of bytes. */
public void writeRawBytes(byte[] value, int offset, int length)
throws IOException {
if (limit - position >= length) {
// We have room in the current buffer.
System.arraycopy(value, offset, buffer, position, length);
position += length;
} else {
// Write extends past current buffer. Fill the rest of this buffer and
// flush.
int bytesWritten = limit - position;
System.arraycopy(value, offset, buffer, position, bytesWritten);
offset += bytesWritten;
length -= bytesWritten;
position = limit;
refreshBuffer();
// Now deal with the rest.
// Since we have an output stream, this is our buffer
// and buffer offset == 0
if (length <= limit) {
// Fits in new buffer.
System.arraycopy(value, offset, buffer, 0, length);
position = length;
} else {
// Write is very big. Let's do it all at once.
output.write(value, offset, length);
}
}
}
/** Encode and write a tag. */
public void writeTag(int fieldNumber, int wireType) throws IOException {
writeRawVarint32(WireFormat.makeTag(fieldNumber, wireType));
}
/** Compute the number of bytes that would be needed to encode a tag. */
public static int computeTagSize(int fieldNumber) {
return computeRawVarint32Size(WireFormat.makeTag(fieldNumber, 0));
}
/**
* Encode and write a varint. {@code value} is treated as
* unsigned, so it won't be sign-extended if negative.
*/
public void writeRawVarint32(int value) throws IOException {
while (true) {
if ((value & ~0x7F) == 0) {
writeRawByte(value);
return;
} else {
writeRawByte((value & 0x7F) | 0x80);
value >>>= 7;
}
}
}
/**
* Compute the number of bytes that would be needed to encode a varint.
* {@code value} is treated as unsigned, so it won't be sign-extended if
* negative.
*/
public static int computeRawVarint32Size(int value) {
if ((value & (0xffffffff << 7)) == 0) return 1;
if ((value & (0xffffffff << 14)) == 0) return 2;
if ((value & (0xffffffff << 21)) == 0) return 3;
if ((value & (0xffffffff << 28)) == 0) return 4;
return 5;
}
/** Encode and write a varint. */
public void writeRawVarint64(long value) throws IOException {
while (true) {
if ((value & ~0x7FL) == 0) {
writeRawByte((int)value);
return;
} else {
writeRawByte(((int)value & 0x7F) | 0x80);
value >>>= 7;
}
}
}
/** Compute the number of bytes that would be needed to encode a varint. */
public static int computeRawVarint64Size(long value) {
if ((value & (0xffffffffffffffffL << 7)) == 0) return 1;
if ((value & (0xffffffffffffffffL << 14)) == 0) return 2;
if ((value & (0xffffffffffffffffL << 21)) == 0) return 3;
if ((value & (0xffffffffffffffffL << 28)) == 0) return 4;
if ((value & (0xffffffffffffffffL << 35)) == 0) return 5;
if ((value & (0xffffffffffffffffL << 42)) == 0) return 6;
if ((value & (0xffffffffffffffffL << 49)) == 0) return 7;
if ((value & (0xffffffffffffffffL << 56)) == 0) return 8;
if ((value & (0xffffffffffffffffL << 63)) == 0) return 9;
return 10;
}
/** Write a little-endian 32-bit integer. */
public void writeRawLittleEndian32(int value) throws IOException {
writeRawByte((value ) & 0xFF);
writeRawByte((value >> 8) & 0xFF);
writeRawByte((value >> 16) & 0xFF);
writeRawByte((value >> 24) & 0xFF);
}
public static final int LITTLE_ENDIAN_32_SIZE = 4;
/** Write a little-endian 64-bit integer. */
public void writeRawLittleEndian64(long value) throws IOException {
writeRawByte((int)(value ) & 0xFF);
writeRawByte((int)(value >> 8) & 0xFF);
writeRawByte((int)(value >> 16) & 0xFF);
writeRawByte((int)(value >> 24) & 0xFF);
writeRawByte((int)(value >> 32) & 0xFF);
writeRawByte((int)(value >> 40) & 0xFF);
writeRawByte((int)(value >> 48) & 0xFF);
writeRawByte((int)(value >> 56) & 0xFF);
}
public static final int LITTLE_ENDIAN_64_SIZE = 8;
/**
* Encode a ZigZag-encoded 32-bit value. ZigZag encodes signed integers
* into values that can be efficiently encoded with varint. (Otherwise,
* negative values must be sign-extended to 64 bits to be varint encoded,
* thus always taking 10 bytes on the wire.)
*
* @param n A signed 32-bit integer.
* @return An unsigned 32-bit integer, stored in a signed int because
* Java has no explicit unsigned support.
*/
public static int encodeZigZag32(int n) {
// Note: the right-shift must be arithmetic
return (n << 1) ^ (n >> 31);
}
/**
* Encode a ZigZag-encoded 64-bit value. ZigZag encodes signed integers
* into values that can be efficiently encoded with varint. (Otherwise,
* negative values must be sign-extended to 64 bits to be varint encoded,
* thus always taking 10 bytes on the wire.)
*
* @param n A signed 64-bit integer.
* @return An unsigned 64-bit integer, stored in a signed int because
* Java has no explicit unsigned support.
*/
public static long encodeZigZag64(long n) {
// Note: the right-shift must be arithmetic
return (n << 1) ^ (n >> 63);
}
}
