Package org.apache.commons.io.input

Class ProxyInputStream

java.lang.Object
java.io.InputStream
java.io.FilterInputStream
org.apache.commons.io.input.ProxyInputStream
All Implemented Interfaces:
Closeable, AutoCloseable
Direct Known Subclasses:
AutoCloseInputStream, BOMInputStream, BoundedInputStream, CloseShieldInputStream, CountingInputStream, MarkShieldInputStream, ObservableInputStream, SwappedDataInputStream, TaggedInputStream, TeeInputStream
public abstract class ProxyInputStream extends FilterInputStream
A proxy stream which acts as a FilterInputStream, by passing all method calls on to the proxied stream, not changing which methods are 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).

In addition, this class allows you to:

  • notify a subclass that n bytes are about to be read through beforeRead(int)
  • notify a subclass that n bytes were read through afterRead(int)
  • notify a subclass that an exception was caught through handleIOException(IOException)
  • unwrap() itself

This class does not add any state (no additional instance variables).

  • Constructor Details

    • ProxyInputStream

      public ProxyInputStream(InputStream proxy)
      Constructs a new ProxyInputStream.
      Parameters:
      proxy - the InputStream to delegate to

  • Method Details

    • available

      public int available() throws IOException
      Invokes the delegate's available() method.
      Overrides:
      available in class FilterInputStream
      Returns:
      the number of available bytes
      Throws:
      IOException - if an I/O error occurs.

    • close

      public void close() throws IOException
      Invokes the delegate's close() method.
      Specified by:
      close in interface AutoCloseable
      Specified by:
      close in interface Closeable
      Overrides:
      close in class FilterInputStream
      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 FilterInputStream
      Parameters:
      readLimit - read ahead limit

    • markSupported

      public boolean markSupported()
      Invokes the delegate's markSupported() method.
      Overrides:
      markSupported in class FilterInputStream
      Returns:
      true if mark is supported, otherwise false

    • read

      public int read() throws IOException
      Invokes the delegate's read() method.
      Overrides:
      read in class FilterInputStream
      Returns:
      the byte read or -1 if the end of stream
      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 FilterInputStream
      Parameters:
      b - the buffer to read the bytes into
      Returns:
      the number of bytes read or EOF if the end of stream
      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 FilterInputStream
      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
      Throws:
      IOException - if an I/O error occurs.

    • reset

      public void reset() throws IOException
      Invokes the delegate's reset() method.
      Overrides:
      reset in class FilterInputStream
      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 FilterInputStream
      Parameters:
      n - the number of bytes to skip
      Returns:
      the actual number of bytes skipped
      Throws:
      IOException - if an I/O error occurs.

    • unwrap

      public InputStream unwrap()
      Unwraps this instance by returning the underlying InputStream.

      Use with caution; useful to query the underlying InputStream.

      Returns:
      the underlying InputStream.
      Since:
      2.16.0