org.apache.commons.io.input

类 ProxyInputStream

java.lang.Object

java.io.InputStream

java.io.FilterInputStream

org.apache.commons.io.input.ProxyInputStream

所有已实现的接口:

Closeable, AutoCloseable

直接已知子类:

AutoCloseInputStream, BOMInputStream, CloseShieldInputStream, CountingInputStream, SwappedDataInputStream, TaggedInputStream, TeeInputStream

public abstract class ProxyInputStream
extends FilterInputStream

A Proxy stream which acts as expected, that is it passes the method calls on to the proxied stream and doesn't change which methods are being called.

It is an alternative base class to FilterInputStream to increase reusability, because FilterInputStream changes the methods being called, such as read(byte[]) to read(byte[], int, int).

See the protected methods for ways in which a subclass can easily decorate a stream with custom pre-, post- or error processing functionality.

字段概要

从类继承的字段 java.io.FilterInputStream

in

构造器概要

构造器

构造器和说明
ProxyInputStream(InputStream proxy) Constructs a new ProxyInputStream.

方法概要

限定符和类型	方法和说明
protected void	afterRead(int n) Invoked by the read methods after the proxied call has returned successfully.
int	available() Invokes the delegate's available() method.
protected void	beforeRead(int n) Invoked by the read methods before the call is proxied.
void	close() Invokes the delegate's close() method.
protected void	handleIOException(IOException e) Handle any IOExceptions thrown.
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.
int	read(byte[] bts) Invokes the delegate's read(byte[]) method.
int	read(byte[] bts, int off, int len) Invokes the delegate's read(byte[], int, int) method.
void	reset() Invokes the delegate's reset() method.
long	skip(long ln) Invokes the delegate's skip(long) method.

从类继承的方法 java.lang.Object

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

构造器详细资料

ProxyInputStream

public ProxyInputStream(InputStream proxy)

Constructs a new ProxyInputStream.

参数:

proxy - the InputStream to delegate to

方法详细资料

read

public int read()
         throws IOException

Invokes the delegate's read() method.

覆盖:

read 在类中 FilterInputStream

返回:

the byte read or -1 if the end of stream

抛出:

IOException - if an I/O error occurs

read

public int read(byte[] bts)
         throws IOException

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

覆盖:

read 在类中 FilterInputStream

参数:

bts - the buffer to read the bytes into

返回:

the number of bytes read or EOF if the end of stream

抛出:

IOException - if an I/O error occurs

read

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

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

覆盖:

read 在类中 FilterInputStream

参数:

bts - the buffer to read the bytes into

off - The start offset

len - The number of bytes to read

返回:

the number of bytes read or -1 if the end of stream

抛出:

IOException - if an I/O error occurs

skip

public long skip(long ln)
          throws IOException

Invokes the delegate's skip(long) method.

覆盖:

skip 在类中 FilterInputStream

参数:

ln - the number of bytes to skip

返回:

the actual number of bytes skipped

抛出:

IOException - if an I/O error occurs

available

public int available()
              throws IOException

Invokes the delegate's available() method.

覆盖:

available 在类中 FilterInputStream

返回:

the number of available bytes

抛出:

IOException - if an I/O error occurs

close

public void close()
           throws IOException

Invokes the delegate's close() method.

指定者:

close 在接口中 Closeable

指定者:

close 在接口中 AutoCloseable

覆盖:

close 在类中 FilterInputStream

抛出:

IOException - if an I/O error occurs

mark

public void mark(int readlimit)

Invokes the delegate's mark(int) method.

覆盖:

mark 在类中 FilterInputStream

参数:

readlimit - read ahead limit

reset

public void reset()
           throws IOException

Invokes the delegate's reset() method.

覆盖:

reset 在类中 FilterInputStream

抛出:

IOException - if an I/O error occurs

markSupported

public boolean markSupported()

Invokes the delegate's markSupported() method.

覆盖:

markSupported 在类中 FilterInputStream

返回:

true if mark is supported, otherwise false

beforeRead

protected void beforeRead(int n)
                   throws IOException

Invoked by the read methods before the call is proxied. The number of bytes that the caller wanted to read (1 for the read() method, buffer length for read(byte[]), etc.) is given as an argument.

Subclasses can override this method to add common pre-processing functionality without having to override all the read methods. The default implementation does nothing.

Note this method is not called from skip(long) or reset(). You need to explicitly override those methods if you want to add pre-processing steps also to them.

参数:

n - number of bytes that the caller asked to be read

抛出:

IOException - if the pre-processing fails

从以下版本开始:

2.0

afterRead

protected void afterRead(int n)
                  throws IOException

Invoked by the read methods after the proxied call has returned successfully. The number of bytes returned to the caller (or -1 if the end of stream was reached) is given as an argument.

Subclasses can override this method to add common post-processing functionality without having to override all the read methods. The default implementation does nothing.

Note this method is not called from skip(long) or reset(). You need to explicitly override those methods if you want to add post-processing steps also to them.

参数:

n - number of bytes read, or -1 if the end of stream was reached

抛出:

IOException - if the post-processing fails

从以下版本开始:

2.0

handleIOException

protected void handleIOException(IOException e)
                          throws IOException

Handle any IOExceptions thrown.

This method provides a point to implement custom exception handling. The default behaviour is to re-throw the exception.

参数:

e - The IOException thrown

抛出:

IOException - if an I/O error occurs

从以下版本开始:

2.0