Module java.desktop
Package javax.imageio.stream

Class FileImageInputStream

java.lang.Object
javax.imageio.stream.ImageInputStreamImpl
javax.imageio.stream.FileImageInputStream
All Implemented Interfaces:
Closeable, DataInput, AutoCloseable, ImageInputStream
public class FileImageInputStream extends ImageInputStreamImpl
An implementation of ImageInputStream that gets its input from a File or RandomAccessFile. The file contents are assumed to be stable during the lifetime of the object.

  • Constructor Details

    • FileImageInputStream

      public FileImageInputStream(File f) throws FileNotFoundException, IOException
      Constructs a FileImageInputStream that will read from a given File.

      The file contents must not change between the time this object is constructed and the time of the last call to a read method.

      Parameters:
      f - a File to read from.
      Throws:
      IllegalArgumentException - if f is null.
      SecurityException - if a security manager exists and does not allow read access to the file.
      FileNotFoundException - if f is a directory or cannot be opened for reading for any other reason.
      IOException - if an I/O error occurs.

    • FileImageInputStream

      public FileImageInputStream(RandomAccessFile raf)
      Constructs a FileImageInputStream that will read from a given RandomAccessFile.

      The file contents must not change between the time this object is constructed and the time of the last call to a read method.

      Parameters:
      raf - a RandomAccessFile to read from.
      Throws:
      IllegalArgumentException - if raf is null.

  • Method Details

    • read

      public int read() throws IOException
      Description copied from class: ImageInputStreamImpl
      Reads a single byte from the stream and returns it as an int between 0 and 255. If EOF is reached, -1 is returned.

      Subclasses must provide an implementation for this method. The subclass implementation should update the stream position before exiting.

      The bit offset within the stream must be reset to zero before the read occurs.

      Specified by:
      read in interface ImageInputStream
      Specified by:
      read in class ImageInputStreamImpl
      Returns:
      the value of the next byte in the stream, or -1 if EOF is reached.
      Throws:
      IOException - if the stream has been closed.

    • read

      public int read(byte[] b, int off, int len) throws IOException
      Description copied from class: ImageInputStreamImpl
      Reads up to len bytes from the stream, and stores them into b starting at index off. If no bytes can be read because the end of the stream has been reached, -1 is returned.

      The bit offset within the stream must be reset to zero before the read occurs.

      Subclasses must provide an implementation for this method. The subclass implementation should update the stream position before exiting.

      Specified by:
      read in interface ImageInputStream
      Specified by:
      read in class ImageInputStreamImpl
      Parameters:
      b - an array of bytes to be written to.
      off - the starting position within b to write to.
      len - the maximum number of bytes to read.
      Returns:
      the number of bytes actually read, or -1 to indicate EOF.
      Throws:
      IOException - if an I/O error occurs.

    • length

      public long length()
      Returns the length of the underlying file, or -1 if it is unknown.
      Specified by:
      length in interface ImageInputStream
      Overrides:
      length in class ImageInputStreamImpl
      Returns:
      the file length as a long, or -1.

    • finalize

      @Deprecated(since="9") protected void finalize() throws Throwable
      Deprecated.
      The finalize method has been deprecated. Subclasses that override finalize in order to perform cleanup should be modified to use alternative cleanup mechanisms and to remove the overriding finalize method. When overriding the finalize method, its implementation must explicitly ensure that super.finalize() is invoked as described in Object.finalize(). See the specification for Object.finalize() for further information about migration options.
      Finalizes this object prior to garbage collection. The close method is called to close any open input source. This method should not be called from application code.
      Overrides:
      finalize in class ImageInputStreamImpl
      Throws:
      Throwable - if an error occurs during superclass finalization.
      See Also: