org.apache.tomcat.util.buf
Class ByteChunk

java.lang.Object
  org.apache.tomcat.util.buf.ByteChunk

All Implemented Interfaces:

java.io.Serializable, java.lang.Cloneable

public final class ByteChunk
extends java.lang.Object
implements java.lang.Cloneable, java.io.Serializable

This class is used to represent a chunk of bytes, and utilities to manipulate byte[]. The buffer can be modified and used for both input and output. There are 2 modes: The chunk can be associated with a sink - ByteInputChannel or ByteOutputChannel, which will be used when the buffer is empty ( on input ) or filled ( on output ). For output, it can also grow. This operating mode is selected by calling setLimit() or allocate(initial, limit) with limit != -1. Various search and append method are defined - similar with String and StringBuffer, but operating on bytes. This is important because it allows processing the http headers directly on the received bytes, without converting to chars and Strings until the strings are needed. In addition, the charset is determined later, from headers or user code.

Author:

dac@sun.com, James Todd [gonzo@sun.com], Costin Manolache, Remy Maucherat

See Also:

Serialized Form

DEFAULT_CHARSET

public static final java.nio.charset.Charset DEFAULT_CHARSET

Default encoding used to convert to strings. It should be UTF8, as most standards seem to converge, but the servlet API requires 8859_1, and this object is used mostly for servlets.

ByteChunk

public ByteChunk()

Creates a new, uninitialized ByteChunk object.

ByteChunk

public ByteChunk(int initial)

getClone

public ByteChunk getClone()

isNull

public boolean isNull()

recycle

public void recycle()

Resets the message buff to an uninitialized state.

reset

public void reset()

allocate

public void allocate(int initial,
                     int limit)

setBytes

public void setBytes(byte[] b,
                     int off,
                     int len)

Sets the message bytes to the specified subarray of bytes.

Parameters:

b - the ascii bytes

off - the start offset of the bytes

len - the length of the bytes

setOptimizedWrite

public void setOptimizedWrite(boolean optimizedWrite)

setCharset

public void setCharset(java.nio.charset.Charset charset)

getCharset

public java.nio.charset.Charset getCharset()

getBytes

public byte[] getBytes()

Returns the message bytes.

getBuffer

public byte[] getBuffer()

Returns the message bytes.

getStart

public int getStart()

Returns the start offset of the bytes. For output this is the end of the buffer.

getOffset

public int getOffset()

setOffset

public void setOffset(int off)

getLength

public int getLength()

Returns the length of the bytes. XXX need to clean this up

setLimit

public void setLimit(int limit)

Maximum amount of data in this buffer. If -1 or not set, the buffer will grow undefinitely. Can be smaller than the current buffer size ( which will not shrink ). When the limit is reached, the buffer will be flushed ( if out is set ) or throw exception.

getLimit

public int getLimit()

setByteInputChannel

public void setByteInputChannel(ByteChunk.ByteInputChannel in)

When the buffer is empty, read the data from the input channel.

setByteOutputChannel

public void setByteOutputChannel(ByteChunk.ByteOutputChannel out)

When the buffer is full, write the data to the output channel. Also used when large amount of data is appended. If not set, the buffer will grow to the limit.

getEnd

public int getEnd()

setEnd

public void setEnd(int i)

append

public void append(char c)
            throws java.io.IOException

Append a char, by casting it to byte. This IS NOT intended for unicode.

Parameters:

c -

Throws:

java.io.IOException

append

public void append(byte b)
            throws java.io.IOException

Throws:

java.io.IOException

append

public void append(ByteChunk src)
            throws java.io.IOException

Throws:

java.io.IOException

append

public void append(byte[] src,
                   int off,
                   int len)
            throws java.io.IOException

Add data to the buffer

Throws:

java.io.IOException

substract

public int substract()
              throws java.io.IOException

Throws:

java.io.IOException

substract

public int substract(ByteChunk src)
              throws java.io.IOException

Throws:

java.io.IOException

substract

public int substract(byte[] src,
                     int off,
                     int len)
              throws java.io.IOException

Throws:

java.io.IOException

flushBuffer

public void flushBuffer()
                 throws java.io.IOException

Send the buffer to the sink. Called by append() when the limit is reached. You can also call it explicitely to force the data to be written.

Throws:

java.io.IOException

toString

public java.lang.String toString()

Overrides:

toString in class java.lang.Object

toStringInternal

public java.lang.String toStringInternal()

getInt

public int getInt()

getLong

public long getLong()

equals

public boolean equals(java.lang.String s)

Compares the message bytes to the specified String object.

Parameters:

s - the String to compare

Returns:

true if the comparison succeeded, false otherwise

equalsIgnoreCase

public boolean equalsIgnoreCase(java.lang.String s)

Compares the message bytes to the specified String object.

Parameters:

s - the String to compare

Returns:

true if the comparison succeeded, false otherwise

equals

public boolean equals(ByteChunk bb)

equals

public boolean equals(byte[] b2,
                      int off2,
                      int len2)

equals

public boolean equals(CharChunk cc)

equals

public boolean equals(char[] c2,
                      int off2,
                      int len2)

startsWith

public boolean startsWith(java.lang.String s)

Returns true if the message bytes starts with the specified string.

Parameters:

s - the string

startsWith

public boolean startsWith(byte[] b2)

startsWithIgnoreCase

public boolean startsWithIgnoreCase(java.lang.String s,
                                    int pos)

Returns true if the message bytes starts with the specified string.

Parameters:

s - the string

pos - The position

indexOf

public int indexOf(java.lang.String src,
                   int srcOff,
                   int srcLen,
                   int myOff)

hash

public int hash()

hashIgnoreCase

public int hashIgnoreCase()

indexOf

public int indexOf(char c,
                   int starting)

Returns true if the message bytes starts with the specified string.

Parameters:

c - the character

starting - The start position

indexOf

public static int indexOf(byte[] bytes,
                          int off,
                          int end,
                          char qq)

findBytes

public static int findBytes(byte[] bytes,
                            int start,
                            int end,
                            byte[] b)

Returns the first instance of any of the given bytes in the byte array between the specified start and end.

Parameters:

bytes - The byte array to search

start - The point to start searching from in the byte array

end - The point to stop searching in the byte array

b - The array of bytes to search for

Returns:

The position of the first instance of the byte or -1 if the byte is not found.

findChar

public static int findChar(byte[] buf,
                           int start,
                           int end,
                           char c)

Find a character, no side effects.

Returns:

index of char if found, -1 if not

findChars

public static int findChars(byte[] buf,
                            int start,
                            int end,
                            byte[] c)

Find a character, no side effects.

Returns:

index of char if found, -1 if not

findNotChars

public static int findNotChars(byte[] buf,
                               int start,
                               int end,
                               byte[] c)

Find the first character != c

Returns:

index of char if found, -1 if not

convertToBytes

public static final byte[] convertToBytes(java.lang.String value)

Convert specified String to a byte array. This ONLY WORKS for ascii, UTF chars will be truncated.

Parameters:

value - to convert to byte array

Returns:

the byte array value