Package io.protostuff
Class CodedInput
- java.lang.Object
-
- io.protostuff.CodedInput
-
- All Implemented Interfaces:
Input
public final class CodedInput extends java.lang.Object implements Input
Reads and decodes protocol message fields.This class contains two kinds of methods: methods that read specific protocol message constructs and field types (e.g.
readTag()andreadInt32()) and methods that read low-level values (e.g.readRawVarint32()andreadRawBytes(int)). If you are reading encoded protocol messages, you should use the former methods, but if you are reading some other format of your own design, use the latter.
-
-
Field Summary
Fields Modifier and Type Field Description private byte[]bufferprivate intbufferPosprivate intbufferSizeprivate intbufferSizeAfterLimitprivate intcurrentLimitThe absolute position of the end of the current message.booleandecodeNestedMessageAsGroupIf true, the nested messages are group-encoded(package private) static intDEFAULT_BUFFER_SIZE(package private) static intDEFAULT_SIZE_LIMITprivate java.io.InputStreaminputprivate intlastTagprivate intpackedLimitprivate intsizeLimitSee setSizeLimit()private inttotalBytesRetiredThe total number of bytes read before the current buffer.
-
Constructor Summary
Constructors Constructor Description CodedInput(byte[] buffer, int off, int len, boolean decodeNestedMessageAsGroup)CodedInput(java.io.InputStream input, boolean decodeNestedMessageAsGroup)CodedInput(java.io.InputStream input, byte[] buffer, boolean decodeNestedMessageAsGroup)CodedInput(java.io.InputStream input, byte[] buffer, int offset, int limit, boolean decodeNestedMessageAsGroup)
-
Method Summary
All Methods Static Methods Instance Methods Concrete Methods Modifier and Type Method Description private voidcheckIfPackedField()Check if this field have been packed into a length-delimited field.voidcheckLastTagWas(int value)Verifies that the last call to readTag() returned the given tag value.static intdecodeZigZag32(int n)Decode a ZigZag-encoded 32-bit value.static longdecodeZigZag64(long n)Decode a ZigZag-encoded 64-bit value.intgetBytesUntilLimit()Returns the number of bytes to be read before the current limit.intgetLastTag()Returns the last tag.intgetTotalBytesRead()The total bytes read up to the current position.<T> voidhandleUnknownField(int fieldNumber, Schema<T> schema)The underlying implementation should handle the unknown field.booleanisAtEnd()Returns true if the stream has reached the end of the input.booleanisCurrentFieldPacked()Return true if currently reading packed field<T> TmergeObject(T value, Schema<T> schema)Merges an object(with schema) field value.private <T> TmergeObjectEncodedAsGroup(T value, Schema<T> schema)Reads a message field value from the stream (using thegroupencoding).static CodedInputnewInstance(byte[] buf)Create a new CodedInput wrapping the given byte array.static CodedInputnewInstance(byte[] buf, int off, int len)Create a new CodedInput wrapping the given byte array slice.static CodedInputnewInstance(java.io.InputStream input)Create a new CodedInput wrapping the given InputStream.voidpopLimit(int oldLimit)Discards the current limit, returning to the previous limit.intpushLimit(int byteLimit)Note thatpushLimit()does NOT affect how many bytes theCodedInputStreamreads from an underlyingInputStreamwhen refreshing its buffer.booleanreadBool()Read aboolfield value from the stream.byte[]readByteArray()Reads a byte array field value.java.nio.ByteBufferreadByteBuffer()Reads a byte array/ByteBuffer value.ByteStringreadBytes()Read abytesfield value from the stream.voidreadBytes(java.nio.ByteBuffer bb)Read astringfield value from the stream into a ByteBuffer.doublereadDouble()Read adoublefield value from the stream.intreadEnum()Read an enum field value from the stream.<T> intreadFieldNumber(Schema<T> schema)Reads the field number of a message/object tied to the givenschema.intreadFixed32()Read afixed32field value from the stream.longreadFixed64()Read afixed64field value from the stream.floatreadFloat()Read afloatfield value from the stream.intreadInt32()Read anint32field value from the stream.longreadInt64()Read anint64field value from the stream.bytereadRawByte()Read one byte from the input.byte[]readRawBytes(int size)Read a fixed size of bytes from the input.intreadRawLittleEndian32()Read a 32-bit little-endian integer from the stream.longreadRawLittleEndian64()Read a 64-bit little-endian integer from the stream.intreadRawVarint32()Read a raw Varint from the stream.(package private) static intreadRawVarint32(java.io.DataInput input, byte firstByte)Reads a varint from the input one byte at a time from aDataInput, so that it does not read any bytes after the end of the varint.(package private) static intreadRawVarint32(java.io.InputStream input)Reads a varint from the input one byte at a time, so that it does not read any bytes after the end of the varint.(package private) static intreadRawVarint32(java.io.InputStream input, int firstByte)Reads a varint from the input one byte at a time, so that it does not read any bytes after the end of the varint.longreadRawVarint64()Read a raw Varint from the stream.intreadSFixed32()Read ansfixed32field value from the stream.longreadSFixed64()Read ansfixed64field value from the stream.intreadSInt32()Read ansint32field value from the stream.longreadSInt64()Read ansint64field value from the stream.java.lang.StringreadString()Read astringfield value from the stream.intreadTag()Attempt to read a field tag, returning zero if we have reached EOF.intreadUInt32()Read auint32field value from the stream.longreadUInt64()Read auint64field value from the stream.private voidrecomputeBufferSizeAfterLimit()private booleanrefillBuffer(boolean mustSucceed)Called withthis.bufferis empty to read more bytes from the input.voidreset()Resets the buffer position and limit to re-use this CodedInput object.voidresetSizeCounter()Resets the current size counter to zero (seesetSizeLimit(int)).intsetSizeLimit(int limit)Set the maximum message size.booleanskipField(int tag)Reads and discards a single field, given its tag value.voidskipMessage()Reads and discards an entire message.voidskipRawBytes(int size)Reads and discardssizebytes.voidtransferByteRangeTo(Output output, boolean utf8String, int fieldNumber, boolean repeated)Transfer the byte range to the output.
-
-
-
Field Detail
-
buffer
private final byte[] buffer
-
bufferSize
private int bufferSize
-
bufferSizeAfterLimit
private int bufferSizeAfterLimit
-
bufferPos
private int bufferPos
-
input
private final java.io.InputStream input
-
lastTag
private int lastTag
-
packedLimit
private int packedLimit
-
totalBytesRetired
private int totalBytesRetired
The total number of bytes read before the current buffer. The total bytes read up to the current position can be computed astotalBytesRetired + bufferPos. This value may be negative if reading started in the middle of the current buffer (e.g. if the constructor that takes a byte array and an offset was used).
-
currentLimit
private int currentLimit
The absolute position of the end of the current message.
-
decodeNestedMessageAsGroup
public final boolean decodeNestedMessageAsGroup
If true, the nested messages are group-encoded
-
sizeLimit
private int sizeLimit
See setSizeLimit()
-
DEFAULT_SIZE_LIMIT
static final int DEFAULT_SIZE_LIMIT
- See Also:
- Constant Field Values
-
DEFAULT_BUFFER_SIZE
static final int DEFAULT_BUFFER_SIZE
- See Also:
- Constant Field Values
-
-
Constructor Detail
-
CodedInput
public CodedInput(byte[] buffer, int off, int len, boolean decodeNestedMessageAsGroup)
-
CodedInput
public CodedInput(java.io.InputStream input, boolean decodeNestedMessageAsGroup)
-
CodedInput
public CodedInput(java.io.InputStream input, byte[] buffer, boolean decodeNestedMessageAsGroup)
-
CodedInput
public CodedInput(java.io.InputStream input, byte[] buffer, int offset, int limit, boolean decodeNestedMessageAsGroup)
-
-
Method Detail
-
newInstance
public static CodedInput newInstance(java.io.InputStream input)
Create a new CodedInput wrapping the given InputStream.
-
newInstance
public static CodedInput newInstance(byte[] buf)
Create a new CodedInput wrapping the given byte array.
-
newInstance
public static CodedInput newInstance(byte[] buf, int off, int len)
Create a new CodedInput wrapping the given byte array slice.
-
readTag
public int readTag() throws java.io.IOExceptionAttempt to read a field tag, returning zero if we have reached EOF. Protocol message parsers use this to read tags, since a protocol message may legally end wherever a tag occurs, and zero is not a valid tag number.- Throws:
java.io.IOException
-
checkLastTagWas
public void checkLastTagWas(int value) throws ProtobufExceptionVerifies that the last call to readTag() returned the given tag value. This is used to verify that a nested group ended with the correct end tag.- Throws:
ProtobufException-valuedoes not match the last tag.
-
skipField
public boolean skipField(int tag) throws java.io.IOExceptionReads and discards a single field, given its tag value.- Returns:
falseif the tag is an endgroup tag, in which case nothing is skipped. Otherwise, returnstrue.- Throws:
java.io.IOException
-
skipMessage
public void skipMessage() throws java.io.IOExceptionReads and discards an entire message. This will read either until EOF or until an endgroup tag, whichever comes first.- Throws:
java.io.IOException
-
readDouble
public double readDouble() throws java.io.IOExceptionRead adoublefield value from the stream.- Specified by:
readDoublein interfaceInput- Throws:
java.io.IOException
-
readFloat
public float readFloat() throws java.io.IOExceptionRead afloatfield value from the stream.
-
readUInt64
public long readUInt64() throws java.io.IOExceptionRead auint64field value from the stream.- Specified by:
readUInt64in interfaceInput- Throws:
java.io.IOException
-
readInt64
public long readInt64() throws java.io.IOExceptionRead anint64field value from the stream.
-
readInt32
public int readInt32() throws java.io.IOExceptionRead anint32field value from the stream.
-
readFixed64
public long readFixed64() throws java.io.IOExceptionRead afixed64field value from the stream.- Specified by:
readFixed64in interfaceInput- Throws:
java.io.IOException
-
readFixed32
public int readFixed32() throws java.io.IOExceptionRead afixed32field value from the stream.- Specified by:
readFixed32in interfaceInput- Throws:
java.io.IOException
-
readBool
public boolean readBool() throws java.io.IOExceptionRead aboolfield value from the stream.
-
readString
public java.lang.String readString() throws java.io.IOExceptionRead astringfield value from the stream.- Specified by:
readStringin interfaceInput- Throws:
java.io.IOException
-
readBytes
public void readBytes(java.nio.ByteBuffer bb) throws java.io.IOExceptionRead astringfield value from the stream into a ByteBuffer.
-
mergeObject
public <T> T mergeObject(T value, Schema<T> schema) throws java.io.IOExceptionDescription copied from interface:InputMerges an object(with schema) field value. The providedschemahandles the deserialization for the object.- Specified by:
mergeObjectin interfaceInput- Throws:
java.io.IOException
-
mergeObjectEncodedAsGroup
private <T> T mergeObjectEncodedAsGroup(T value, Schema<T> schema) throws java.io.IOExceptionReads a message field value from the stream (using thegroupencoding).- Throws:
java.io.IOException
-
readBytes
public ByteString readBytes() throws java.io.IOException
Read abytesfield value from the stream.
-
readUInt32
public int readUInt32() throws java.io.IOExceptionRead auint32field value from the stream.- Specified by:
readUInt32in interfaceInput- Throws:
java.io.IOException
-
readEnum
public int readEnum() throws java.io.IOExceptionRead an enum field value from the stream. Caller is responsible for converting the numeric value to an actual enum.
-
readSFixed32
public int readSFixed32() throws java.io.IOExceptionRead ansfixed32field value from the stream.- Specified by:
readSFixed32in interfaceInput- Throws:
java.io.IOException
-
readSFixed64
public long readSFixed64() throws java.io.IOExceptionRead ansfixed64field value from the stream.- Specified by:
readSFixed64in interfaceInput- Throws:
java.io.IOException
-
readSInt32
public int readSInt32() throws java.io.IOExceptionRead ansint32field value from the stream.- Specified by:
readSInt32in interfaceInput- Throws:
java.io.IOException
-
readSInt64
public long readSInt64() throws java.io.IOExceptionRead ansint64field value from the stream.- Specified by:
readSInt64in interfaceInput- Throws:
java.io.IOException
-
readRawVarint32
public int readRawVarint32() throws java.io.IOExceptionRead a raw Varint from the stream. If larger than 32 bits, discard the upper bits.- Throws:
java.io.IOException
-
readRawVarint32
static int readRawVarint32(java.io.InputStream input) throws java.io.IOExceptionReads a varint from the input one byte at a time, so that it does not read any bytes after the end of the varint. If you simply wrapped the stream in a CodedInput and usedreadRawVarint32(InputStream)then you would probably end up reading past the end of the varint since CodedInput buffers its input.- Throws:
java.io.IOException
-
readRawVarint32
static int readRawVarint32(java.io.InputStream input, int firstByte) throws java.io.IOExceptionReads a varint from the input one byte at a time, so that it does not read any bytes after the end of the varint. If you simply wrapped the stream in a CodedInput and usedreadRawVarint32(InputStream)then you would probably end up reading past the end of the varint since CodedInput buffers its input.- Throws:
java.io.IOException
-
readRawVarint32
static int readRawVarint32(java.io.DataInput input, byte firstByte) throws java.io.IOExceptionReads a varint from the input one byte at a time from aDataInput, so that it does not read any bytes after the end of the varint.- Throws:
java.io.IOException
-
readRawVarint64
public long readRawVarint64() throws java.io.IOExceptionRead a raw Varint from the stream.- Throws:
java.io.IOException
-
readRawLittleEndian32
public int readRawLittleEndian32() throws java.io.IOExceptionRead a 32-bit little-endian integer from the stream.- Throws:
java.io.IOException
-
readRawLittleEndian64
public long readRawLittleEndian64() throws java.io.IOExceptionRead a 64-bit little-endian integer from the stream.- Throws:
java.io.IOException
-
decodeZigZag32
public static int decodeZigZag32(int n)
Decode 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.)- Parameters:
n- An unsigned 32-bit integer, stored in a signed int because Java has no explicit unsigned support.- Returns:
- A signed 32-bit integer.
-
decodeZigZag64
public static long decodeZigZag64(long n)
Decode 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.)- Parameters:
n- An unsigned 64-bit integer, stored in a signed int because Java has no explicit unsigned support.- Returns:
- A signed 64-bit integer.
-
setSizeLimit
public int setSizeLimit(int limit)
Set the maximum message size. In order to prevent malicious messages from exhausting memory or causing integer overflows,CodedInputlimits how large a message may be. The default limit is 64MB. You should set this limit as small as you can without harming your app's functionality. Note that size limits only apply when reading from anInputStream, not when constructed around a raw byte array.If you want to read several messages from a single CodedInput, you could call
resetSizeCounter()after each one to avoid hitting the size limit.- Returns:
- the old limit.
-
resetSizeCounter
public void resetSizeCounter()
Resets the current size counter to zero (seesetSizeLimit(int)). The fieldtotalBytesRetiredwill be negative if the initial position was not zero.
-
reset
public void reset()
Resets the buffer position and limit to re-use this CodedInput object.
-
pushLimit
public int pushLimit(int byteLimit) throws ProtobufExceptionNote thatpushLimit()does NOT affect how many bytes theCodedInputStreamreads from an underlyingInputStreamwhen refreshing its buffer. If you need to prevent reading past a certain point in the underlyingInputStream(e.g. because you expect it to contain more data after the end of the message which you need to handle differently) then you must place a wrapper around yourInputStreamwhich limits the amount of data that can be read from it.- Returns:
- the old limit.
- Throws:
ProtobufException
-
recomputeBufferSizeAfterLimit
private void recomputeBufferSizeAfterLimit()
-
popLimit
public void popLimit(int oldLimit)
Discards the current limit, returning to the previous limit.- Parameters:
oldLimit- The old limit, as returned bypushLimit.
-
getBytesUntilLimit
public int getBytesUntilLimit()
Returns the number of bytes to be read before the current limit. If no limit is set, returns -1.
-
isCurrentFieldPacked
public boolean isCurrentFieldPacked()
Return true if currently reading packed field
-
isAtEnd
public boolean isAtEnd() throws java.io.IOExceptionReturns true if the stream has reached the end of the input. This is the case if either the end of the underlying input source has been reached or if the stream has reached a limit created usingpushLimit(int).- Throws:
java.io.IOException
-
getTotalBytesRead
public int getTotalBytesRead()
The total bytes read up to the current position. CallingresetSizeCounter()resets this value to zero.
-
refillBuffer
private boolean refillBuffer(boolean mustSucceed) throws java.io.IOExceptionCalled withthis.bufferis empty to read more bytes from the input. IfmustSucceedis true, refillBuffer() guarantees that either there will be at least one byte in the buffer when it returns or it will throw an exception. IfmustSucceedis false, refillBuffer() returns false if no more bytes were available.- Throws:
java.io.IOException
-
readRawByte
public byte readRawByte() throws java.io.IOExceptionRead one byte from the input.- Throws:
ProtobufException- The end of the stream or the current limit was reached.java.io.IOException
-
readRawBytes
public byte[] readRawBytes(int size) throws java.io.IOExceptionRead a fixed size of bytes from the input.- Throws:
ProtobufException- The end of the stream or the current limit was reached.java.io.IOException
-
skipRawBytes
public void skipRawBytes(int size) throws java.io.IOExceptionReads and discardssizebytes.- Throws:
ProtobufException- The end of the stream or the current limit was reached.java.io.IOException
-
readFieldNumber
public <T> int readFieldNumber(Schema<T> schema) throws java.io.IOException
Description copied from interface:InputReads the field number of a message/object tied to the givenschema.- Specified by:
readFieldNumberin interfaceInput- Throws:
java.io.IOException
-
checkIfPackedField
private void checkIfPackedField() throws java.io.IOExceptionCheck if this field have been packed into a length-delimited field. If so, update internal state to reflect that packed fields are being read.- Throws:
java.io.IOException
-
readByteArray
public byte[] readByteArray() throws java.io.IOExceptionDescription copied from interface:InputReads a byte array field value.- Specified by:
readByteArrayin interfaceInput- Throws:
java.io.IOException
-
handleUnknownField
public <T> void handleUnknownField(int fieldNumber, Schema<T> schema) throws java.io.IOExceptionDescription copied from interface:InputThe underlying implementation should handle the unknown field.- Specified by:
handleUnknownFieldin interfaceInput- Throws:
java.io.IOException
-
transferByteRangeTo
public void transferByteRangeTo(Output output, boolean utf8String, int fieldNumber, boolean repeated) throws java.io.IOException
Description copied from interface:InputTransfer the byte range to the output. Capable of zero-copy transfer depending on the type of input.- Specified by:
transferByteRangeToin interfaceInput- Throws:
java.io.IOException
-
getLastTag
public int getLastTag()
Returns the last tag.
-
readByteBuffer
public java.nio.ByteBuffer readByteBuffer() throws java.io.IOExceptionReads a byte array/ByteBuffer value.- Specified by:
readByteBufferin interfaceInput- Throws:
java.io.IOException
-
-