com.aliyun.core.io

Class BoundedInputStream

java.lang.Object

java.io.InputStream

com.aliyun.core.io.BoundedInputStream

All Implemented Interfaces:

Closeable, AutoCloseable

public class BoundedInputStream
extends InputStream

This is a stream that will only supply bytes up to a certain length - if its position goes above that, it will stop.

This is useful to wrap ServletInputStreams. The ServletInputStream will block if you try to read content from it that isn't there, because it doesn't know whether the content hasn't arrived yet or whether the content has finished. So, one of these, initialized with the Content-length sent in the ServletInputStream's header, will stop it blocking, providing it's been sent with a correct content length.

Since:

2.1.1

Constructor Summary

Constructors

Constructor and Description
BoundedInputStream(InputStream in) Creates a new BoundedInputStream that wraps the given input stream and is unlimited.
BoundedInputStream(InputStream in, long size) Creates a new BoundedInputStream that wraps the given input stream and limits it to a certain size.

Method Summary

Modifier and Type	Method and Description
int	available()
protected void	backoff(long backoff) Go back current position
void	close() Invokes the delegate's close() method if isPropagateClose() is true.
InputStream	getWrappedInputStream() Get original input stream
boolean	isPropagateClose() Indicates whether the close() method should propagate to the underling InputStream.
void	mark(int readlimit) Invokes the delegate's mark(int) method.
boolean	markSupported() Invokes the delegate's markSupported() method.
int	read() Invokes the delegate's read() method if the current position is less than the limit.
int	read(byte[] b) Invokes the delegate's read(byte[]) method.
int	read(byte[] b, int off, int len) Invokes the delegate's read(byte[], int, int) method.
void	reset() Invokes the delegate's reset() method.
void	setPropagateClose(boolean propagateClose) Set whether the close() method should propagate to the underling InputStream.
long	skip(long n) Invokes the delegate's skip(long) method.
String	toString() Invokes the delegate's toString() method.

Methods inherited from class java.lang.Object

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

Constructor Detail

BoundedInputStream

public BoundedInputStream(InputStream in,
                          long size)

Creates a new BoundedInputStream that wraps the given input stream and limits it to a certain size.

Parameters:

in - The wrapped input stream

size - The maximum number of bytes to return

BoundedInputStream

public BoundedInputStream(InputStream in)

Creates a new BoundedInputStream that wraps the given input stream and is unlimited.

Parameters:

in - The wrapped input stream

Method Detail

read

public int read()
         throws IOException

Invokes the delegate's read() method if the current position is less than the limit.

Specified by:

read in class InputStream

Returns:

the byte read or -1 if the end of stream or the limit has been reached.

Throws:

IOException - if an I/O error occurs

read

public int read(byte[] b)
         throws IOException

Invokes the delegate's read(byte[]) method.

Overrides:

read in class InputStream

Parameters:

b - the buffer to read the bytes into

Returns:

the number of bytes read or -1 if the end of stream or the limit has been reached.

Throws:

IOException - if an I/O error occurs

read

public int read(byte[] b,
                int off,
                int len)
         throws IOException

Invokes the delegate's read(byte[], int, int) method.

Overrides:

read in class InputStream

Parameters:

b - the buffer to read the bytes into

off - The start offset

len - The number of bytes to read

Returns:

the number of bytes read or -1 if the end of stream or the limit has been reached.

Throws:

IOException - if an I/O error occurs

skip

public long skip(long n)
          throws IOException

Invokes the delegate's skip(long) method.

Overrides:

skip in class InputStream

Parameters:

n - the number of bytes to skip

Returns:

the actual number of bytes skipped

Throws:

IOException - if an I/O error occurs

available

public int available()
              throws IOException

Overrides:

available in class InputStream

Throws:

IOException

toString

public String toString()

Invokes the delegate's toString() method.

Overrides:

toString in class Object

Returns:

the delegate's toString()

close

public void close()
           throws IOException

Invokes the delegate's close() method if isPropagateClose() is true.

Specified by:

close in interface Closeable

Specified by:

close in interface AutoCloseable

Overrides:

close in class InputStream

Throws:

IOException - if an I/O error occurs

reset

public void reset()
           throws IOException

Invokes the delegate's reset() method.

Overrides:

reset in class InputStream

Throws:

IOException - if an I/O error occurs

mark

public void mark(int readlimit)

Invokes the delegate's mark(int) method.

Overrides:

mark in class InputStream

Parameters:

readlimit - read ahead limit

markSupported

public boolean markSupported()

Invokes the delegate's markSupported() method.

Overrides:

markSupported in class InputStream

Returns:

true if mark is supported, otherwise false

isPropagateClose

public boolean isPropagateClose()

Indicates whether the close() method should propagate to the underling InputStream.

Returns:

true if calling close() propagates to the close() method of the underlying stream or false if it does not.

setPropagateClose

public void setPropagateClose(boolean propagateClose)

Set whether the close() method should propagate to the underling InputStream.

Parameters:

propagateClose - true if calling close() propagates to the close() method of the underlying stream or false if it does not.

getWrappedInputStream

public InputStream getWrappedInputStream()

Get original input stream

Returns:

original input stream

backoff

protected void backoff(long backoff)

Go back current position

Parameters:

backoff -