Module org.refcodes.io
Package org.refcodes.io

Class AvailableInputStream

java.lang.Object
java.io.InputStream
org.refcodes.io.TimeoutInputStream
org.refcodes.io.AvailableInputStream
All Implemented Interfaces:
Closeable, AutoCloseable, org.refcodes.mixin.ReadTimeoutMillisAccessor
public class AvailableInputStream extends TimeoutInputStream
The AvailableInputStream decorates an InputStream with time-out functionality using the TimeoutInputStream.available() method. This decorator works only when the decorated InputStream returns realistic values when calling InputStream.available(). This is most probably the case e.g. for serial communication (TTY/COM) as those devices usually buffer for incoming bytes. If this cannot be guaranteed, please use the TimeoutInputStream! The benefit of the AvailableInputStream over the TimeoutInputStream is that the AvailableInputStream does not use any additional threads for asynchronous operation so it is a good fit for IoT devices!

  • Constructor Details

    • AvailableInputStream

      public AvailableInputStream(InputStream aInputStream, long aTimeoutMillis)
      Constructs a AvailableInputStream decorating an InputStream with additional timeout functionality.
      Parameters:
      aInputStream - The InputStream to be decorated.
      aTimeoutMillis - The default timeout for read operations not explicitly called with a timeout argument. With a value of -1 timeout handling is disabled (blocking mode).

    • AvailableInputStream

      public AvailableInputStream(InputStream aInputStream, Long aTimeoutMillis)
      Constructs a AvailableInputStream decorating an InputStream with additional timeout functionality.
      Parameters:
      aInputStream - The InputStream to be decorated.
      aTimeoutMillis - The default timeout for read operations not explicitly called with a timeout argument. With a value of -1 timeout handling is disabled (blocking mode).

    • AvailableInputStream

      public AvailableInputStream(InputStream aInputStream, Object aMonitor)
      Constructs a AvailableInputStream decorating an InputStream with additional timeout functionality.
      Parameters:
      aInputStream - The InputStream to be decorated.
      aMonitor - The monitor to use when waiting the poll loop time. This is useful required available data can be read before the poll loop time expires. E.g. an underlying system might call Object.notifyAll() on the monitor as soon as it received new data.

    • AvailableInputStream

      public AvailableInputStream(InputStream aInputStream)
      Constructs a AvailableInputStream decorating an InputStream with additional timeout functionality.
      Parameters:
      aInputStream - The InputStream to be decorated.

    • AvailableInputStream

      public AvailableInputStream(InputStream aInputStream, long aTimeoutMillis, Object aMonitor)
      Constructs a AvailableInputStream decorating an InputStream with additional timeout functionality.
      Parameters:
      aInputStream - The InputStream to be decorated.
      aTimeoutMillis - The default timeout for read operations not explicitly called with a timeout argument. With a value of -1 timeout handling is disabled (blocking mode).
      aMonitor - The monitor to use when waiting the poll loop time. This is useful required available data can be read before the poll loop time expires. E.g. an underlying system might call Object.notifyAll() on the monitor as soon as it received new data.

  • Method Details

    • read

      public int read(long aTimeoutMillis) throws IOException
      Enriches the TimeoutInputStream.read() method with a timeout. This methods blocks till the result is available and can be returned or the timeout is reached. A timeout of -1 disables the timeout.
      Overrides:
      read in class TimeoutInputStream
      Parameters:
      aTimeoutMillis - The timeout in milliseconds to wait for the next byte available.With a value of -1 timeout handling is disabled (blocking mode).
      Returns:
      The next byte of data, or -1 if the end of the stream is reached.
      Throws:
      IOException - thrown in case of according I/O related problems or an expired timeout.

    • read

      public int read(byte[] b, int off, int len, long aTimeoutMillis) throws IOException
      Enriches the TimeoutInputStream.read(byte[], int, int) method with a timeout. This methods blocks till the result is available and can be returned or the timeout is reached. A timeout of -1 disables the timeout.
      Overrides:
      read in class TimeoutInputStream
      Parameters:
      b - The byte array into which the data is read.
      off - The start offset in b at which the data is written.
      len - The maximum number of bytes to read.
      aTimeoutMillis - The timeout in milliseconds to wait for the next byte available.With a value of -1 timeout handling is disabled (blocking mode).
      Returns:
      The total number of bytes read into the buffer, or -1 if there is no more data because the end of the stream has been reached.
      Throws:
      IOException - thrown in case of according I/O related problems or an expired timeout.

    • read

      public int read(byte[] b, long aTimeoutMillis) throws IOException
      Enriches the TimeoutInputStream.read(byte[]) method with a timeout. This methods blocks till the result is available and can be returned or the timeout is reached. A timeout of -1 disables the timeout. Calling this method has the same effect a read(b, 0, b.length), so we try to read as many bytes as the buffer's length is.
      Overrides:
      read in class TimeoutInputStream
      Parameters:
      b - The byte array into which the data is read.
      aTimeoutMillis - The timeout in milliseconds to wait for the next byte available.With a value of -1 timeout handling is disabled (blocking mode).
      Returns:
      The total number of bytes read into the buffer, or -1 if there is no more data because the end of the stream has been reached.
      Throws:
      IOException - thrown in case of according I/O related problems or an expired timeout.

    • readNBytes

      public int readNBytes(byte[] b, int off, int len, long aTimeoutMillis) throws IOException
      Enriches the TimeoutInputStream.readNBytes(byte[], int, int) method with a timeout. This methods blocks till the result is available and can be returned or the timeout is reached. A timeout of -1 disables the timeout.
      Overrides:
      readNBytes in class TimeoutInputStream
      Parameters:
      b - the byte array into which the data is read
      off - the start offset in b at which the data is written
      len - the maximum number of bytes to read
      aTimeoutMillis - The timeout in milliseconds.
      Returns:
      the actual number of bytes read into the buffer
      Throws:
      IOException - if an I/O error occurs

    • readNBytes

      public byte[] readNBytes(int len, long aTimeoutMillis) throws IOException
      Enriches the TimeoutInputStream.readNBytes(int) method with a timeout. This methods blocks till the result is available and can be returned or the timeout is reached. A timeout of -1 disables the timeout.
      Overrides:
      readNBytes in class TimeoutInputStream
      Parameters:
      len - the maximum number of bytes to read
      aTimeoutMillis - The timeout in milliseconds.
      Returns:
      The byte array containing the bytes read from this input stream
      Throws:
      IOException - Signals that an I/O exception has occurred.