Package org.zkoss.io

Class RepeatableInputStream

  • All Implemented Interfaces:
    java.io.Closeable, java.io.Serializable, java.lang.AutoCloseable, Repeatable
    public class RepeatableInputStream
extends java.io.InputStream
implements Repeatable, java.io.Serializable
    RepeatableInputStream adds functionality to another input stream, the ability to read repeatedly. By repeatable-read we mean, after close(), the next invocation of read() will re-open the input stream.

    RepeatableInputStream actually creates a temporary space to buffer the content, so it can be re-opened again after closed. Notice that the temporary space (a.k.a., the buffered input stream) is never closed until garbage-collected.

    If the content size of the given input stream is smaller than the value specified in the system property called "org.zkoss.io.memoryLimitSize", the content will be buffered in the memory. If the size exceeds, the content will be buffered in a temporary file. By default, it is 512KB. Note: the maximal value is Integer.MAX_VALUE

    If the content size of the given input stream is larger than the value specified in the system property called "org.zkoss.io.bufferLimitSize", the content won't be buffered, and it means the read is not repeatable. By default, it is 20MB. Note: the maximal value is Integer.MAX_VALUE

    Since:
    3.0.4
    Author:
    jumperchen, tomyeh
    See Also:
    Serialized Form

    • Method Summary

      All Methods Static Methods Instance Methods Concrete Methods 
      Modifier and Type Method Description
      void close()
      Closes the current access, and the next call of close() re-opens the buffered input stream.
      static java.io.InputStream getInstance​(java.io.File file)
      Returns an input stream of a file that can be read repeatedly.
      static java.io.InputStream getInstance​(java.io.InputStream is)
      Returns an input stream that can be read repeatedly, or null if the given input stream is null.
      static java.io.InputStream getInstance​(java.lang.String filename)
      Returns an input stream of a file that can be read repeatedly.
      static java.io.InputStream getInstance​(java.net.URL url)
      Returns an input stream of the resource of the given URL that can be read repeatedly.
      int read()  
      int read​(byte[] b, int off, int len)  

      • Methods inherited from class java.io.InputStream

        available, mark, markSupported, nullInputStream, read, readAllBytes, readNBytes, readNBytes, reset, skip, transferTo

      • Methods inherited from class java.lang.Object

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

    • Method Detail

      • getInstance

        public static java.io.InputStream getInstance​(java.io.InputStream is)
        Returns an input stream that can be read repeatedly, or null if the given input stream is null. Note: the returned input stream encapsulates the given input stream, rd (a.k.a., the buffered input stream) to adds the functionality to re-opens the input stream once close() is called.

        By repeatable-read we mean, after close(), the next invocation of read() will re-open the input stream.

        Use this method instead of instantiating RepeatableInputStream with the constructor.

        See Also:
        getInstance(File)

      • getInstance

        public static java.io.InputStream getInstance​(java.io.File file)
                                       throws java.io.FileNotFoundException
        Returns an input stream of a file that can be read repeatedly. Note: it assumes the file is binary (rather than text).

        By repeatable-read we mean, after close(), the next invocation of read() will re-open the input stream.

        Note: it is efficient since we don't have to buffer the content of the file to make it repeatable-read.

        Throws:
        java.lang.IllegalArgumentException - if file is null.
        java.io.FileNotFoundException - if file not found
        See Also:
        getInstance(InputStream), getInstance(String)

      • getInstance

        public static java.io.InputStream getInstance​(java.lang.String filename)
                                       throws java.io.FileNotFoundException
        Returns an input stream of a file that can be read repeatedly. Note: it assumes the file is binary (rather than text).

        By repeatable-read we mean, after close(), the next invocation of read() will re-open the input stream.

        Note: it is efficient since we don't have to buffer the content of the file to make it repeatable-read.

        Throws:
        java.lang.IllegalArgumentException - if file is null.
        java.io.FileNotFoundException
        See Also:
        getInstance(InputStream), getInstance(File)

      • getInstance

        public static java.io.InputStream getInstance​(java.net.URL url)
        Returns an input stream of the resource of the given URL that can be read repeatedly. Note: it assumes the resource is binary (rather than text).

        By repeatable-read we mean, after close(), the next invocation of read() will re-open the input stream.

        Note: it is efficient since we don't have to buffer the content of the resource to make it repeatable-read.

        Throws:
        java.lang.IllegalArgumentException - if url is null.
        See Also:
        getInstance(InputStream), getInstance(String)

      • read

        public int read()
         throws java.io.IOException
        Specified by:
        read in class java.io.InputStream
        Throws:
        java.io.IOException

      • read

        public int read​(byte[] b,
                int off,
                int len)
         throws java.io.IOException
        Overrides:
        read in class java.io.InputStream
        Throws:
        java.io.IOException

      • close

        public void close()
           throws java.io.IOException
        Closes the current access, and the next call of close() re-opens the buffered input stream.
        Specified by:
        close in interface java.lang.AutoCloseable
        Specified by:
        close in interface java.io.Closeable
        Overrides:
        close in class java.io.InputStream
        Throws:
        java.io.IOException