Package de.aristaflow.adept2.util.io

Class BufferedRereadableContent

  • All Implemented Interfaces:
    Closeable, AutoCloseable
    public class BufferedRereadableContent
extends Object
implements Closeable
    The BufferedRereadableContent can be used when the content of an InputStream needs to be processed multiple times. Depending on its eventual size the whole content of the input stream is buffered in-memory - up to a certain threshold - or in a temporary file.

    The BufferedRereadableContent as well as the provided input streams must be closed after use! This can be ensured by adhering to the following template: 

     
 try (TemporaryRereadableInput input = new TemporaryRereadableInput(inputStream))
 {
   ...
   try (InputStream is = input.getInputStream())
   {
     ...
   }
   ...
   try (InputStream is = input.getInputStream())
   {
     ...
   }
   ...
 }

    • Constructor Detail

      • BufferedRereadableContent

        public BufferedRereadableContent​(InputStream inputStream,
                                 int threshold,
                                 String tempFileTag,
                                 File tempDir)
                          throws IOException
        Creates a new BufferedRereadableContent and immediately reads the given InputStream.

        ByteArrayInputStreams will receive special treatment to avoid creating a duplicate of their content.

        Parameters:
        inputStream - the input stream to read
        threshold - the number of bytes after which to store the content in a file instead; negative values will result in the default threshold
        tempFileTag - an optional tag that will be incorporated into the name of the temp file if one is created; may be null
        tempDir - the directory where temp files should be created; may be null to use the default temp directory of the JVM; will be created if it doesn't exist
        Throws:
        IOException - if an I/O error occurs

    • Method Detail

      • getLength

        public long getLength()
        Returns the total length of the content.
        Returns:
        the total length of the content

      • getInputStream

        public InputStream getInputStream()
                           throws IOException
        Returns an input stream for the data. This method may be called multiple times. But not while previously acquired streams are still being used. The returned stream must be closed properly after use!
        Returns:
        an input stream for the data
        Throws:
        IOException - if an I/O error occurs