bayou.bytes

Class RangedByteSource

java.lang.Object

bayou.bytes.RangedByteSource

All Implemented Interfaces:

ByteSource

public class RangedByteSource
extends Object
implements ByteSource

A sub-range [min, max) of an origin source.

The `min` limit is inclusive. The `max` limit is exclusive.

For example, an origin source contains 10 bytes {b₀, ..., b₉}. The sub-range [min=3, max=8) will contain 5 bytes {b₃, ..., b₇}.

Both `min` and `max` can go beyond the range of the origin source. If the origin source contains 10 bytes, sub-range [3, Long.MAX_VALUE) is valid, containing 7 bytes; sub-range [10, 20) is also valid, containing 0 bytes.

This class uses the skip(n) method on the origin source. Note that `origin.skip(n)` does not need to actually skip n bytes; this class can skip the origin by read and discard bytes.

Constructor Summary

Constructors

Constructor and Description
RangedByteSource(ByteSource origin, long min, long max) Create a sub-range [min, max) of the origin source.

Method Summary

Instance Methods
long	getMin() Get the min limit of the range.
long	getMax() Get the max limit of the range.
long	skip(long n) Try to skip forward `n` bytes.
Async<ByteBuffer>	read() Read the next chunk of bytes.
Async<Void>	close() Close this source.

Methods inherited from class java.lang.Object

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

Methods inherited from interface bayou.bytes.ByteSource

asString, asString, readAll, toSink

Constructor Detail

RangedByteSource

public RangedByteSource(ByteSource origin,
                        long min,
                        long max)

Create a sub-range [min, max) of the origin source.

Required: 0<=min<=max.

Note that it is legal if max>=L or min>=L where L is the length of the origin source.

Method Detail

getMin

public long getMin()

Get the min limit of the range.

getMax

public long getMax()

Get the max limit of the range.

skip

public long skip(long n)
          throws IllegalArgumentException,
                 IllegalStateException

Try to skip forward `n` bytes.

Specified by:

skip in interface ByteSource

Parameters:

n - number of bytes to skip; n >= 0.

Returns:

number of bytes (m) actually skipped. 0 <= m <= n.

Throws:

IllegalStateException - if this source is closed.

IllegalArgumentException - if n < 0.

read

public Async<ByteBuffer> read()
                       throws IllegalStateException

Read the next chunk of bytes.

Specified by:

read in interface ByteSource

Throws:

IllegalStateException - if this source is closed.

close

public Async<Void> close()

Close this source.

Specified by:

close in interface ByteSource