Package org.apache.commons.io.input.buffer

Class PeekableInputStream

  • All Implemented Interfaces:
    java.io.Closeable, java.lang.AutoCloseable
    public class PeekableInputStream
extends CircularBufferInputStream
    Implements a buffered input stream, which allows to peek into the buffers first bytes. This comes in handy when manually implementing scanners, lexers, parsers, and the like.

    • Constructor Summary

      Constructors 
      Constructor Description
      PeekableInputStream​(java.io.InputStream inputStream)
      Constructs a new instance, which filters the given input stream, and uses a reasonable default buffer size (IOUtils.DEFAULT_BUFFER_SIZE).
      PeekableInputStream​(java.io.InputStream inputStream, int bufferSize)
      Constructs a new instance, which filters the given input stream, and uses the given buffer size.

    • Method Summary

      All Methods Instance Methods Concrete Methods 
      Modifier and Type Method Description
      boolean peek​(byte[] sourceBuffer)
      Returns whether the next bytes in the buffer are as given by sourceBuffer.
      boolean peek​(byte[] sourceBuffer, int offset, int length)
      Returns whether the next bytes in the buffer are as given by sourceBuffer, {code offset}, and length.

      • Methods inherited from class java.io.FilterInputStream

        available, mark, markSupported, read, reset, skip

      • Methods inherited from class java.io.InputStream

        nullInputStream, readAllBytes, readNBytes, readNBytes, transferTo

      • Methods inherited from class java.lang.Object

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

    • Constructor Detail

      • PeekableInputStream

        public PeekableInputStream​(java.io.InputStream inputStream)
        Constructs a new instance, which filters the given input stream, and uses a reasonable default buffer size (IOUtils.DEFAULT_BUFFER_SIZE).
        Parameters:
        inputStream - The input stream, which is being buffered.

      • PeekableInputStream

        public PeekableInputStream​(java.io.InputStream inputStream,
                           int bufferSize)
        Constructs a new instance, which filters the given input stream, and uses the given buffer size.
        Parameters:
        inputStream - The input stream, which is being buffered.
        bufferSize - The size of the CircularByteBuffer, which is used internally.

    • Method Detail

      • peek

        public boolean peek​(byte[] sourceBuffer)
             throws java.io.IOException
        Returns whether the next bytes in the buffer are as given by sourceBuffer. This is equivalent to peek(byte[], int, int) with offset == 0, and length == sourceBuffer.length
        Parameters:
        sourceBuffer - the buffer to compare against
        Returns:
        true if the next bytes are as given
        Throws:
        java.io.IOException - Refilling the buffer failed.

      • peek

        public boolean peek​(byte[] sourceBuffer,
                    int offset,
                    int length)
             throws java.io.IOException
        Returns whether the next bytes in the buffer are as given by sourceBuffer, {code offset}, and length.
        Parameters:
        sourceBuffer - the buffer to compare against
        offset - the start offset
        length - the length to compare
        Returns:
        true if the next bytes in the buffer are as given
        Throws:
        java.io.IOException - if there is a problem calling fillBuffer()