FileCacheImageInputStream (Java SE 15 & JDK 15) (original) (raw)

All Implemented Interfaces:

[Closeable](../../../../java.base/java/io/Closeable.html "interface in java.io"), [DataInput](../../../../java.base/java/io/DataInput.html "interface in java.io"), [AutoCloseable](../../../../java.base/java/lang/AutoCloseable.html "interface in java.lang"), [ImageInputStream](ImageInputStream.html "interface in javax.imageio.stream")

public class FileCacheImageInputStream extends ImageInputStreamImpl

An implementation of ImageInputStream that gets its input from a regular InputStream. A file is used to cache previously read data.

• Field Summary

• Constructor Summary

Constructors

• Method Summary

Methods declared in interface javax.imageio.stream.ImageInputStream

[flush](ImageInputStream.html#flush%28%29), [flushBefore](ImageInputStream.html#flushBefore%28long%29), [getBitOffset](ImageInputStream.html#getBitOffset%28%29), [getByteOrder](ImageInputStream.html#getByteOrder%28%29), [getFlushedPosition](ImageInputStream.html#getFlushedPosition%28%29), [getStreamPosition](ImageInputStream.html#getStreamPosition%28%29), [readBit](ImageInputStream.html#readBit%28%29), [readBits](ImageInputStream.html#readBits%28int%29), [readBoolean](ImageInputStream.html#readBoolean%28%29), [readByte](ImageInputStream.html#readByte%28%29), [readBytes](ImageInputStream.html#readBytes%28javax.imageio.stream.IIOByteBuffer,int%29), [readChar](ImageInputStream.html#readChar%28%29), [readDouble](ImageInputStream.html#readDouble%28%29), [readFloat](ImageInputStream.html#readFloat%28%29), [readFully](ImageInputStream.html#readFully%28byte%5B%5D%29), [readFully](ImageInputStream.html#readFully%28byte%5B%5D,int,int%29), [readFully](ImageInputStream.html#readFully%28char%5B%5D,int,int%29), [readFully](ImageInputStream.html#readFully%28double%5B%5D,int,int%29), [readFully](ImageInputStream.html#readFully%28float%5B%5D,int,int%29), [readFully](ImageInputStream.html#readFully%28int%5B%5D,int,int%29), [readFully](ImageInputStream.html#readFully%28long%5B%5D,int,int%29), [readFully](ImageInputStream.html#readFully%28short%5B%5D,int,int%29), [readInt](ImageInputStream.html#readInt%28%29), [readLine](ImageInputStream.html#readLine%28%29), [readLong](ImageInputStream.html#readLong%28%29), [readShort](ImageInputStream.html#readShort%28%29), [readUnsignedByte](ImageInputStream.html#readUnsignedByte%28%29), [readUnsignedInt](ImageInputStream.html#readUnsignedInt%28%29), [readUnsignedShort](ImageInputStream.html#readUnsignedShort%28%29), [readUTF](ImageInputStream.html#readUTF%28%29), [seek](ImageInputStream.html#seek%28long%29), [setBitOffset](ImageInputStream.html#setBitOffset%28int%29), [setByteOrder](ImageInputStream.html#setByteOrder%28java.nio.ByteOrder%29)

• Constructor Details

  • FileCacheImageInputStream

  Constructs a FileCacheImageInputStream that will read from a given InputStream.
  A temporary file is used as a cache. IfcacheDir is non-null and is a directory, the file will be created there. If it isnull, the system-dependent default temporary-file directory will be used (see the documentation forFile.createTempFile for details).
  Parameters:
  stream - an InputStream to read from.
  cacheDir - a File indicating where the cache file should be created, or null to use the system directory.
  Throws:
  [IllegalArgumentException](../../../../java.base/java/lang/IllegalArgumentException.html "class in java.lang") - if stream isnull.
  [IllegalArgumentException](../../../../java.base/java/lang/IllegalArgumentException.html "class in java.lang") - if cacheDir is non-null but is not a directory.
  [IOException](../../../../java.base/java/io/IOException.html "class in java.io") - if a cache file cannot be created.

• Method Details

  • isCached

  public boolean isCached()
  Returns true since thisImageInputStream caches data in order to allow seeking backwards.
  Specified by:
  [isCached](ImageInputStream.html#isCached%28%29) in interface [ImageInputStream](ImageInputStream.html "interface in javax.imageio.stream")
  Overrides:
  [isCached](ImageInputStreamImpl.html#isCached%28%29) in class [ImageInputStreamImpl](ImageInputStreamImpl.html "class in javax.imageio.stream")
  Returns:
  true.
  See Also:
  isCachedMemory(), isCachedFile()

  • isCachedFile

  public boolean isCachedFile()
  Returns true since thisImageInputStream maintains a file cache.
  Specified by:
  [isCachedFile](ImageInputStream.html#isCachedFile%28%29) in interface [ImageInputStream](ImageInputStream.html "interface in javax.imageio.stream")
  Overrides:
  [isCachedFile](ImageInputStreamImpl.html#isCachedFile%28%29) in class [ImageInputStreamImpl](ImageInputStreamImpl.html "class in javax.imageio.stream")
  Returns:
  true.
  See Also:
  isCached(), isCachedMemory()

  • isCachedMemory

  public boolean isCachedMemory()
  Returns false since thisImageInputStream does not maintain a main memory cache.
  Specified by:
  [isCachedMemory](ImageInputStream.html#isCachedMemory%28%29) in interface [ImageInputStream](ImageInputStream.html "interface in javax.imageio.stream")
  Overrides:
  [isCachedMemory](ImageInputStreamImpl.html#isCachedMemory%28%29) in class [ImageInputStreamImpl](ImageInputStreamImpl.html "class in javax.imageio.stream")
  Returns:
  false.
  See Also:
  isCached(), isCachedFile()

  • close

  Closes this FileCacheImageInputStream, closing and removing the cache file. The source InputStream is not closed.
  Throws:
  [IOException](../../../../java.base/java/io/IOException.html "class in java.io") - if an error occurs.

  • finalize

  Finalizes this object prior to garbage collection. Theclose method is called to close any open input source. This method should not be called from application code.
  Overrides:
  [finalize](ImageInputStreamImpl.html#finalize%28%29) in class [ImageInputStreamImpl](ImageInputStreamImpl.html "class in javax.imageio.stream")
  Throws:
  [Throwable](../../../../java.base/java/lang/Throwable.html "class in java.lang") - if an error occurs during superclass finalization.
  See Also:
  WeakReference, PhantomReference