net.pwall.util

Class ByteArrayBuilder

java.lang.Object

net.pwall.util.ByteArrayBuilder

public class ByteArrayBuilder
extends Object

A dynamic byte array class. This class allows byte array to be created dynamically, similar to a StringBuilder for strings. ByteArrayOutputStream also provides equivalent functionality, but its write methods are synchronized.

Author:

Peter Wall

Field Summary

Fields

Modifier and Type	Field and Description
static int	MINIMUM_READ_BUFFER_SIZE

Constructor Summary

Constructors

Constructor and Description
ByteArrayBuilder() Construct a ByteArrayBuilder with the default initial size of 20.
ByteArrayBuilder(byte[] array) Construct a ByteArrayBuilder from an existing byte array.
ByteArrayBuilder(ByteArrayBuilder bab) Construct a ByteArrayBuilder from another ByteArrayBuilder.
ByteArrayBuilder(int size) Construct a ByteArrayBuilder with the specified initial size.
ByteArrayBuilder(int size, int increment) Construct a ByteArrayBuilder with the specified initial size and increment.

Method Summary

Modifier and Type	Method and Description
ByteArrayBuilder	append(byte[] array) Append a byte array.
ByteArrayBuilder	append(byte[] array, int start, int end) Append a specified range of bytes from a byte array.
ByteArrayBuilder	append(ByteArrayBuilder bab) Append another ByteArrayBuilder.
ByteArrayBuilder	append(InputStream is) Append the contents of an InputStream.
ByteArrayBuilder	append(int b) Append an int as a single byte.
ByteArrayBuilder	create() Convenience method to create a ByteArrayBuilder.
ByteArrayBuilder	create(int size) Convenience method to create a ByteArrayBuilder, specifying the initial size.
byte	get(int index) Get a nominated byte from the array.
ByteArrayBuilder	insert(int index, byte[] array) Insert a byte array at the nominated point in the array.
ByteArrayBuilder	insert(int index, ByteArrayBuilder bab) Insert another ByteArrayBuilder at the nominated point in the array.
ByteArrayBuilder	insert(int index, int b) Insert an int as a single byte at the nominated point in the array.
int	length() Get the length of the ByteArrayBuilder (the number of bytes used).
byte	set(int index, int value) Set a nominated byte in the array to a given value.
byte[]	toByteArray() Get a byte array of only the bytes used.
byte[]	toByteArray(int start) Get a byte array of only the bytes used, starting from a nominated point.
byte[]	toByteArray(int start, int end) Get a byte array of only the bytes used, using a nominated start and end point.

Methods inherited from class java.lang.Object

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

Field Detail

MINIMUM_READ_BUFFER_SIZE

public static final int MINIMUM_READ_BUFFER_SIZE

See Also:

Constant Field Values

Constructor Detail

ByteArrayBuilder

public ByteArrayBuilder(int size,
                        int increment)

Construct a ByteArrayBuilder with the specified initial size and increment.

Parameters:

size - the initial size (may be zero)

increment - the amount to increment the size by when necessary

Throws:

IllegalArgumentException - if the size is negative or the increment is not positive

ByteArrayBuilder

public ByteArrayBuilder(int size)

Construct a ByteArrayBuilder with the specified initial size.

Parameters:

size - the initial size

Throws:

IllegalArgumentException - if the size is negative

ByteArrayBuilder

public ByteArrayBuilder()

Construct a ByteArrayBuilder with the default initial size of 20.

ByteArrayBuilder

public ByteArrayBuilder(byte[] array)

Construct a ByteArrayBuilder from an existing byte array.

Parameters:

array - the byte array

ByteArrayBuilder

public ByteArrayBuilder(ByteArrayBuilder bab)

Construct a ByteArrayBuilder from another ByteArrayBuilder.

Parameters:

bab - the other ByteArrayBuilder

Method Detail

length

public int length()

Get the length of the ByteArrayBuilder (the number of bytes used).

Returns:

the current length

toByteArray

public byte[] toByteArray()

Get a byte array of only the bytes used.

Returns:

the byte array

toByteArray

public byte[] toByteArray(int start)

Get a byte array of only the bytes used, starting from a nominated point.

Parameters:

start - the start index

Returns:

the byte array

Throws:

IndexOutOfBoundsException - if the start index is outside the bounds of the array

toByteArray

public byte[] toByteArray(int start,
                          int end)

Get a byte array of only the bytes used, using a nominated start and end point.

Parameters:

start - the start index

end - the end index

Returns:

the byte array

Throws:

IndexOutOfBoundsException - if the start or end index is not valid

set

public byte set(int index,
                int value)

Set a nominated byte in the array to a given value.

Parameters:

index - the index to be modified

value - the new value

Returns:

the previous value at that index

Throws:

IndexOutOfBoundsException - if the index is not valid

get

public byte get(int index)

Get a nominated byte from the array.

Parameters:

index - the index of the byte

Returns:

the value at that index

Throws:

IndexOutOfBoundsException - if the index is not valid

append

public ByteArrayBuilder append(int b)

Append an int as a single byte.

Parameters:

b - the new value

Returns:

this (for chaining)

append

public ByteArrayBuilder append(byte[] array)

Append a byte array.

Parameters:

array - the byte array

Returns:

this (for chaining)

append

public ByteArrayBuilder append(byte[] array,
                               int start,
                               int end)

Append a specified range of bytes from a byte array.

Parameters:

array - the byte array

start - the start index

end - the end index

Returns:

this (for chaining)

append

public ByteArrayBuilder append(ByteArrayBuilder bab)

Append another ByteArrayBuilder.

Parameters:

bab - the other ByteArrayBuilder

Returns:

this (for chaining)

append

public ByteArrayBuilder append(InputStream is)
                        throws IOException

Append the contents of an InputStream.

Parameters:

is - the InputStream

Returns:

this (for chaining)

Throws:

IOException - if thrown by the InputStream

insert

public ByteArrayBuilder insert(int index,
                               int b)

Insert an int as a single byte at the nominated point in the array. All following bytes will be moved up make room.

Parameters:

index - the index at which to insert

b - the new value

Returns:

this (for chaining)

Throws:

IndexOutOfBoundsException - if the index is not valid

insert

public ByteArrayBuilder insert(int index,
                               byte[] array)

Insert a byte array at the nominated point in the array. All following bytes will be moved up make room.

Parameters:

index - the index at which to insert

array - the byte array

Returns:

this (for chaining)

Throws:

IndexOutOfBoundsException - if the index is not valid

insert

public ByteArrayBuilder insert(int index,
                               ByteArrayBuilder bab)

Insert another ByteArrayBuilder at the nominated point in the array. All following bytes will be moved up make room.

Parameters:

index - the index at which to insert

bab - the other ByteArrayBuilder

Returns:

this (for chaining)

Throws:

IndexOutOfBoundsException - if the index is not valid

create

public ByteArrayBuilder create()

Convenience method to create a ByteArrayBuilder. Supports the idiom:

     ByteArrayBuilder bab = ByteArrayBuilder.create().append(0).append(1).append(2);
 

Returns:

the new ByteArrayBuilder

create

public ByteArrayBuilder create(int size)

Convenience method to create a ByteArrayBuilder, specifying the initial size. Supports the idiom (for example):

     InputStream is = new FileInputStream("data.bin");
     byte[] fileContents = ByteArrayBuilder.create(1000).append(is).toByteArray();
 

Parameters:

size - the initial size

Returns:

the new ByteArrayBuilder

Throws:

IllegalArgumentException - if the size is negative