Package com.google.protobuf

Class Utf8.Processor

java.lang.Object

com.google.protobuf.Utf8.Processor

Direct Known Subclasses:

Utf8.SafeProcessor, Utf8.UnsafeProcessor

Enclosing class:

Utf8

abstract static class Utf8.Processor
extends java.lang.Object

A processor of UTF-8 strings, providing methods for checking validity and encoding.

Constructor Summary

Constructors

Constructor	Description
Processor()

Method Summary

Modifier and Type	Method	Description
(package private) abstract java.lang.String	decodeUtf8(byte[] bytes, int index, int size)	Decodes the given byte array slice into a String.
(package private) java.lang.String	decodeUtf8(java.nio.ByteBuffer buffer, int index, int size)	Decodes the given portion of the ByteBuffer into a String.
(package private) java.lang.String	decodeUtf8Default(java.nio.ByteBuffer buffer, int index, int size)	Decodes ByteBuffer instances using the ByteBuffer API rather than potentially faster approaches.
(package private) abstract java.lang.String	decodeUtf8Direct(java.nio.ByteBuffer buffer, int index, int size)	Decodes direct ByteBuffer instances into String.
(package private) abstract int	encodeUtf8(java.lang.String in, byte[] out, int offset, int length)	Encodes an input character sequence (in) to UTF-8 in the target array (out).
(package private) void	encodeUtf8(java.lang.String in, java.nio.ByteBuffer out)	Encodes an input character sequence (in) to UTF-8 in the target buffer (out).
protected abstract void	encodeUtf8Internal(java.lang.String in, java.nio.ByteBuffer out)	Encodes the input character sequence to a direct ByteBuffer instance.
protected int	encodeUtf8Naive(java.lang.String in, byte[] out, int offset, int length)
protected void	encodeUtf8Naive(java.lang.String in, java.nio.ByteBuffer out)
(package private) abstract boolean	isValidUtf8(byte[] bytes, int index, int limit)	Returns true if the given byte array slice is a well-formed UTF-8 byte sequence.
protected boolean	isValidUtf8BufferDefault(java.nio.ByteBuffer buffer, int index, int limit)	Returns true if the given portion of the ByteBuffer is a well-formed UTF-8 byte sequence.
protected boolean	isValidUtf8BufferDirect(java.nio.ByteBuffer buffer, int index, int limit)	Must only be called on Direct buffers.

Methods inherited from class java.lang.Object

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

Constructor Detail

Processor

Processor()

Method Detail

isValidUtf8

abstract boolean isValidUtf8(byte[] bytes,
                             int index,
                             int limit)

Returns true if the given byte array slice is a well-formed UTF-8 byte sequence. The range of bytes to be checked extends from index index, inclusive, to limit, exclusive.

isValidUtf8BufferDirect

protected boolean isValidUtf8BufferDirect(java.nio.ByteBuffer buffer,
                                          int index,
                                          int limit)

Must only be called on Direct buffers. This exists as a separate method only so that the UnsafeProcessor can optimize specially for that case.

isValidUtf8BufferDefault

protected boolean isValidUtf8BufferDefault(java.nio.ByteBuffer buffer,
                                           int index,
                                           int limit)

Returns true if the given portion of the ByteBuffer is a well-formed UTF-8 byte sequence. The range of bytes to be checked extends from index index, inclusive, to limit, exclusive.

decodeUtf8

abstract java.lang.String decodeUtf8(byte[] bytes,
                                     int index,
                                     int size)
                              throws InvalidProtocolBufferException

Decodes the given byte array slice into a String.

Throws:

InvalidProtocolBufferException - if the byte array slice is not valid UTF-8

decodeUtf8

final java.lang.String decodeUtf8(java.nio.ByteBuffer buffer,
                                  int index,
                                  int size)
                           throws InvalidProtocolBufferException

Decodes the given portion of the ByteBuffer into a String.

Throws:

InvalidProtocolBufferException - if the portion of the buffer is not valid UTF-8

decodeUtf8Direct

abstract java.lang.String decodeUtf8Direct(java.nio.ByteBuffer buffer,
                                           int index,
                                           int size)
                                    throws InvalidProtocolBufferException

Decodes direct ByteBuffer instances into String.

Throws:

InvalidProtocolBufferException

decodeUtf8Default

final java.lang.String decodeUtf8Default(java.nio.ByteBuffer buffer,
                                         int index,
                                         int size)
                                  throws InvalidProtocolBufferException

Decodes ByteBuffer instances using the ByteBuffer API rather than potentially faster approaches.

Throws:

InvalidProtocolBufferException

encodeUtf8Naive

protected int encodeUtf8Naive(java.lang.String in,
                              byte[] out,
                              int offset,
                              int length)

encodeUtf8Naive

protected void encodeUtf8Naive(java.lang.String in,
                               java.nio.ByteBuffer out)

encodeUtf8

abstract int encodeUtf8(java.lang.String in,
                        byte[] out,
                        int offset,
                        int length)

Encodes an input character sequence (in) to UTF-8 in the target array (out). For a string, this method is functionally identical to

 byte[] a = string.getBytes(UTF_8);
 System.arraycopy(a, 0, bytes, offset, a.length);
 return offset + a.length;
 

but may be implemented differently for efficiency purposes.

Matching String.getBytes(UTF_8) this replaces unpaired surrogates with a replacement character.

To ensure sufficient space in the output buffer, either call Utf8.encodedLength(java.lang.String) to compute the exact amount needed, or leave room for Utf8.MAX_BYTES_PER_CHAR * sequence.length(), which is the largest possible number of bytes that any input can be encoded to.

Parameters:

in - the input character sequence to be encoded

out - the target array

offset - the starting offset in bytes to start writing at

length - the length of the bytes, starting from offset

Returns:

the new offset, equivalent to offset + Utf8.encodedLength(sequence)

Throws:

java.lang.ArrayIndexOutOfBoundsException - if sequence encoded in UTF-8 is longer than bytes.length - offset

encodeUtf8

final void encodeUtf8(java.lang.String in,
                      java.nio.ByteBuffer out)

Encodes an input character sequence (in) to UTF-8 in the target buffer (out). Upon returning from this method, the out position will point to the position after the last encoded byte. This method requires paired surrogates, and therefore does not support chunking.

To ensure sufficient space in the output buffer, either call Utf8.encodedLength(java.lang.String) to compute the exact amount needed, or leave room for Utf8.MAX_BYTES_PER_CHAR * in.length(), which is the largest possible number of bytes that any input can be encoded to.

Parameters:

in - the source character sequence to be encoded

out - the target buffer

Throws:

java.lang.ArrayIndexOutOfBoundsException - if in encoded in UTF-8 is longer than out.remaining()

encodeUtf8Internal

protected abstract void encodeUtf8Internal(java.lang.String in,
                                           java.nio.ByteBuffer out)

Encodes the input character sequence to a direct ByteBuffer instance.