Package org.openstreetmap.josm.data.protobuf

Class ProtobufParser

java.lang.Object

org.openstreetmap.josm.data.protobuf.ProtobufParser

All Implemented Interfaces:

java.lang.AutoCloseable

public class ProtobufParser
extends java.lang.Object
implements java.lang.AutoCloseable

A basic Protobuf parser

Since:

17862

Field Summary

Fields

Modifier and Type	Field	Description
static byte	BYTE_SIZE	The default byte size (see VAR_INT_BYTE_SIZE for var ints)
private static byte[]	EMPTY_BYTE_ARRAY
private java.io.InputStream	inputStream
(package private) static byte	MOST_SIGNIFICANT_BYTE	Used to get the most significant byte
static byte	VAR_INT_BYTE_SIZE	The byte size for var ints (since the first byte is just an indicator for if the var int is done)

Constructor Summary

Constructors

Constructor	Description
ProtobufParser(byte[] bytes)	Create a new parser
ProtobufParser(java.io.InputStream inputStream)	Create a new parser

Method Summary

Modifier and Type	Method	Description
java.util.Collection<ProtobufRecord>	allRecords()	Read all records
void	close()
static java.lang.Number	convertByteArray(byte[] bytes, byte byteSize)	Convert a byte array to a number (little endian)
static long	convertByteArray(byte[] bytes, byte byteSize, int start, int end)	Convert a byte array to a number (little endian)
static java.lang.Number	convertLong(long number)	Convert a long to an appropriate Number class
static long	decodeZigZag(long signed)	Decode a zig-zag encoded value
static java.lang.Number	decodeZigZag(java.lang.Number signed)	Decode a zig-zag encoded value
static java.lang.Number	encodeZigZag(java.lang.Number signed)	Encode a number to a zig-zag encode value
boolean	hasNext()	Check if there is more data to read
WireType	next()	Get the "next" WireType
int	nextByte()	Get the next byte
byte[]	nextFixed32()	Get the next 32 bits (WireType.THIRTY_TWO_BIT)
byte[]	nextFixed64()	Get the next 64 bits (WireType.SIXTY_FOUR_BIT)
byte[]	nextLengthDelimited(java.io.ByteArrayOutputStream byteArrayOutputStream)	Get the next delimited message (WireType.LENGTH_DELIMITED)
byte[]	nextVarInt(java.io.ByteArrayOutputStream byteArrayOutputStream)	Get the next var int (WireType#VARINT)
private byte[]	readNextBytes(int size)	Read an arbitrary number of bytes

Methods inherited from class java.lang.Object

clone, equals, finalize, getClass, hashCode, notify, notifyAll, toString, wait, wait, wait

Field Detail

BYTE_SIZE

public static final byte BYTE_SIZE

The default byte size (see VAR_INT_BYTE_SIZE for var ints)

See Also:

Constant Field Values

VAR_INT_BYTE_SIZE

public static final byte VAR_INT_BYTE_SIZE

The byte size for var ints (since the first byte is just an indicator for if the var int is done)

See Also:

Constant Field Values

MOST_SIGNIFICANT_BYTE

static final byte MOST_SIGNIFICANT_BYTE

Used to get the most significant byte

See Also:

Constant Field Values

EMPTY_BYTE_ARRAY

private static final byte[] EMPTY_BYTE_ARRAY

inputStream

private final java.io.InputStream inputStream

Constructor Detail

ProtobufParser

public ProtobufParser(byte[] bytes)

Create a new parser

Parameters:

bytes - The bytes to parse

ProtobufParser

public ProtobufParser(java.io.InputStream inputStream)

Create a new parser

Parameters:

inputStream - The InputStream (will be fully read at this time)

Method Detail

convertByteArray

public static java.lang.Number convertByteArray(byte[] bytes,
                                                byte byteSize)

Convert a byte array to a number (little endian)

Parameters:

bytes - The bytes to convert

byteSize - The size of the byte. For var ints, this is 7, for other ints, this is 8.

Returns:

An appropriate Number class.

convertByteArray

public static long convertByteArray(byte[] bytes,
                                    byte byteSize,
                                    int start,
                                    int end)

Convert a byte array to a number (little endian)

Parameters:

bytes - The bytes to convert

byteSize - The size of the byte. For var ints, this is 7, for other ints, this is 8.

start - The start position in the byte array

end - The end position in the byte array (exclusive - [start, end) )

Returns:

the number from the byte array. Depending upon length of time the number will be stored, narrowing may be helpful.

Since:

18695

convertLong

public static java.lang.Number convertLong(long number)

Convert a long to an appropriate Number class

Parameters:

number - The long to convert

Returns:

A Number

decodeZigZag

public static java.lang.Number decodeZigZag(java.lang.Number signed)

Decode a zig-zag encoded value

Parameters:

signed - The value to decode

Returns:

The decoded value

decodeZigZag

public static long decodeZigZag(long signed)

Decode a zig-zag encoded value

Parameters:

signed - The value to decode

Returns:

The decoded value

Since:

18695

encodeZigZag

public static java.lang.Number encodeZigZag(java.lang.Number signed)

Encode a number to a zig-zag encode value

Parameters:

signed - The number to encode

Returns:

The encoded value

allRecords

public java.util.Collection<ProtobufRecord> allRecords()
                                                throws java.io.IOException

Read all records

Returns:

A collection of all records

Throws:

java.io.IOException - - if an IO error occurs

close

public void close()

Specified by:

close in interface java.lang.AutoCloseable

hasNext

public boolean hasNext()
                throws java.io.IOException

Check if there is more data to read

Returns:

true if there is more data to read

Throws:

java.io.IOException - - if an IO error occurs

next

public WireType next()
              throws java.io.IOException

Get the "next" WireType

Returns:

WireType expected

Throws:

java.io.IOException - - if an IO error occurs

nextByte

public int nextByte()
             throws java.io.IOException

Get the next byte

Returns:

The next byte

Throws:

java.io.IOException - - if an IO error occurs

nextFixed32

public byte[] nextFixed32()
                   throws java.io.IOException

Get the next 32 bits (WireType.THIRTY_TWO_BIT)

Returns:

a byte array of the next 32 bits (4 bytes)

Throws:

java.io.IOException - - if an IO error occurs

nextFixed64

public byte[] nextFixed64()
                   throws java.io.IOException

Get the next 64 bits (WireType.SIXTY_FOUR_BIT)

Returns:

a byte array of the next 64 bits (8 bytes)

Throws:

java.io.IOException - - if an IO error occurs

nextLengthDelimited

public byte[] nextLengthDelimited(java.io.ByteArrayOutputStream byteArrayOutputStream)
                           throws java.io.IOException

Get the next delimited message (WireType.LENGTH_DELIMITED)

Parameters:

byteArrayOutputStream - A reusable stream to write bytes to. This can significantly reduce the allocations (150 MB to 95 MB in a test area).

Returns:

The next length delimited message

Throws:

java.io.IOException - - if an IO error occurs

nextVarInt

public byte[] nextVarInt(java.io.ByteArrayOutputStream byteArrayOutputStream)
                  throws java.io.IOException

Get the next var int (WireType#VARINT)

Parameters:

byteArrayOutputStream - A reusable stream to write bytes to. This can significantly reduce the allocations (150 MB to 95 MB in a test area).

Returns:

The next var int (int32, int64, uint32, uint64, bool, enum)

Throws:

java.io.IOException - - if an IO error occurs

readNextBytes

private byte[] readNextBytes(int size)
                      throws java.io.IOException

Read an arbitrary number of bytes

Parameters:

size - The number of bytes to read

Returns:

a byte array filled with bytes read (unsigned)

Throws:

java.io.IOException - - if an IO error occurs