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src/java.desktop/share/classes/javax/imageio/spi/ImageInputStreamSpi.java
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*** 29,170 ****
import java.io.IOException;
import javax.imageio.stream.ImageInputStream;
/**
* The service provider interface (SPI) for
! * <code>ImageInputStream</code>s. For more information on service
* provider interfaces, see the class comment for the
! * <code>IIORegistry</code> class.
*
* <p> This interface allows arbitrary objects to be "wrapped" by
! * instances of <code>ImageInputStream</code>. For example,
! * a particular <code>ImageInputStreamSpi</code> might allow
! * a generic <code>InputStream</code> to be used as an input source;
! * another might take input from a <code>URL</code>.
*
! * <p> By treating the creation of <code>ImageInputStream</code>s as a
* pluggable service, it becomes possible to handle future input
* sources without changing the API. Also, high-performance
! * implementations of <code>ImageInputStream</code> (for example,
* native implementations for a particular platform) can be installed
* and used transparently by applications.
*
* @see IIORegistry
* @see javax.imageio.stream.ImageInputStream
*
*/
public abstract class ImageInputStreamSpi extends IIOServiceProvider {
/**
! * A <code>Class</code> object indicating the legal object type
! * for use by the <code>createInputStreamInstance</code> method.
*/
protected Class<?> inputClass;
/**
! * Constructs a blank <code>ImageInputStreamSpi</code>. It is up
* to the subclass to initialize instance variables and/or
* override method implementations in order to provide working
* versions of all methods.
*/
protected ImageInputStreamSpi() {
}
/**
! * Constructs an <code>ImageInputStreamSpi</code> with a given set
* of values.
*
* @param vendorName the vendor name.
* @param version a version identifier.
! * @param inputClass a <code>Class</code> object indicating the
* legal object type for use by the
! * <code>createInputStreamInstance</code> method.
*
! * @exception IllegalArgumentException if <code>vendorName</code>
! * is <code>null</code>.
! * @exception IllegalArgumentException if <code>version</code>
! * is <code>null</code>.
*/
public ImageInputStreamSpi(String vendorName,
String version,
Class<?> inputClass) {
super(vendorName, version);
this.inputClass = inputClass;
}
/**
! * Returns a <code>Class</code> object representing the class or
* interface type that must be implemented by an input source in
! * order to be "wrapped" in an <code>ImageInputStream</code> via
! * the <code>createInputStreamInstance</code> method.
*
* <p> Typical return values might include
! * <code>InputStream.class</code> or <code>URL.class</code>, but
* any class may be used.
*
! * @return a <code>Class</code> variable.
*
* @see #createInputStreamInstance(Object, boolean, File)
*/
public Class<?> getInputClass() {
return inputClass;
}
/**
! * Returns <code>true</code> if the <code>ImageInputStream</code>
* implementation associated with this service provider can
* optionally make use of a cache file for improved performance
! * and/or memory footrprint. If <code>false</code>, the value of
! * the <code>useCache</code> argument to
! * <code>createInputStreamInstance</code> will be ignored.
*
! * <p> The default implementation returns <code>false</code>.
*
! * @return <code>true</code> if a cache file can be used by the
* input streams created by this service provider.
*/
public boolean canUseCacheFile() {
return false;
}
/**
! * Returns <code>true</code> if the <code>ImageInputStream</code>
* implementation associated with this service provider requires
! * the use of a cache <code>File</code>. If <code>true</code>,
! * the value of the <code>useCache</code> argument to
! * <code>createInputStreamInstance</code> will be ignored.
*
! * <p> The default implementation returns <code>false</code>.
*
! * @return <code>true</code> if a cache file is needed by the
* input streams created by this service provider.
*/
public boolean needsCacheFile() {
return false;
}
/**
! * Returns an instance of the <code>ImageInputStream</code>
* implementation associated with this service provider. If the
! * use of a cache file is optional, the <code>useCache</code>
* parameter will be consulted. Where a cache is required, or
! * not applicable, the value of <code>useCache</code> will be ignored.
*
* @param input an object of the class type returned by
! * <code>getInputClass</code>.
! * @param useCache a <code>boolean</code> indicating whether a
* cache file should be used, in cases where it is optional.
! * @param cacheDir a <code>File</code> indicating where the
! * cache file should be created, or <code>null</code> to use the
* system directory.
*
! * @return an <code>ImageInputStream</code> instance.
*
! * @exception IllegalArgumentException if <code>input</code> is
! * not an instance of the correct class or is <code>null</code>.
* @exception IllegalArgumentException if a cache file is needed
! * but <code>cacheDir</code> is non-<code>null</code> and is not a
* directory.
* @exception IOException if a cache file is needed but cannot be
* created.
*
* @see #getInputClass
--- 29,170 ----
import java.io.IOException;
import javax.imageio.stream.ImageInputStream;
/**
* The service provider interface (SPI) for
! * {@code ImageInputStream}s. For more information on service
* provider interfaces, see the class comment for the
! * {@code IIORegistry} class.
*
* <p> This interface allows arbitrary objects to be "wrapped" by
! * instances of {@code ImageInputStream}. For example,
! * a particular {@code ImageInputStreamSpi} might allow
! * a generic {@code InputStream} to be used as an input source;
! * another might take input from a {@code URL}.
*
! * <p> By treating the creation of {@code ImageInputStream}s as a
* pluggable service, it becomes possible to handle future input
* sources without changing the API. Also, high-performance
! * implementations of {@code ImageInputStream} (for example,
* native implementations for a particular platform) can be installed
* and used transparently by applications.
*
* @see IIORegistry
* @see javax.imageio.stream.ImageInputStream
*
*/
public abstract class ImageInputStreamSpi extends IIOServiceProvider {
/**
! * A {@code Class} object indicating the legal object type
! * for use by the {@code createInputStreamInstance} method.
*/
protected Class<?> inputClass;
/**
! * Constructs a blank {@code ImageInputStreamSpi}. It is up
* to the subclass to initialize instance variables and/or
* override method implementations in order to provide working
* versions of all methods.
*/
protected ImageInputStreamSpi() {
}
/**
! * Constructs an {@code ImageInputStreamSpi} with a given set
* of values.
*
* @param vendorName the vendor name.
* @param version a version identifier.
! * @param inputClass a {@code Class} object indicating the
* legal object type for use by the
! * {@code createInputStreamInstance} method.
*
! * @exception IllegalArgumentException if {@code vendorName}
! * is {@code null}.
! * @exception IllegalArgumentException if {@code version}
! * is {@code null}.
*/
public ImageInputStreamSpi(String vendorName,
String version,
Class<?> inputClass) {
super(vendorName, version);
this.inputClass = inputClass;
}
/**
! * Returns a {@code Class} object representing the class or
* interface type that must be implemented by an input source in
! * order to be "wrapped" in an {@code ImageInputStream} via
! * the {@code createInputStreamInstance} method.
*
* <p> Typical return values might include
! * {@code InputStream.class} or {@code URL.class}, but
* any class may be used.
*
! * @return a {@code Class} variable.
*
* @see #createInputStreamInstance(Object, boolean, File)
*/
public Class<?> getInputClass() {
return inputClass;
}
/**
! * Returns {@code true} if the {@code ImageInputStream}
* implementation associated with this service provider can
* optionally make use of a cache file for improved performance
! * and/or memory footrprint. If {@code false}, the value of
! * the {@code useCache} argument to
! * {@code createInputStreamInstance} will be ignored.
*
! * <p> The default implementation returns {@code false}.
*
! * @return {@code true} if a cache file can be used by the
* input streams created by this service provider.
*/
public boolean canUseCacheFile() {
return false;
}
/**
! * Returns {@code true} if the {@code ImageInputStream}
* implementation associated with this service provider requires
! * the use of a cache {@code File}. If {@code true},
! * the value of the {@code useCache} argument to
! * {@code createInputStreamInstance} will be ignored.
*
! * <p> The default implementation returns {@code false}.
*
! * @return {@code true} if a cache file is needed by the
* input streams created by this service provider.
*/
public boolean needsCacheFile() {
return false;
}
/**
! * Returns an instance of the {@code ImageInputStream}
* implementation associated with this service provider. If the
! * use of a cache file is optional, the {@code useCache}
* parameter will be consulted. Where a cache is required, or
! * not applicable, the value of {@code useCache} will be ignored.
*
* @param input an object of the class type returned by
! * {@code getInputClass}.
! * @param useCache a {@code boolean} indicating whether a
* cache file should be used, in cases where it is optional.
! * @param cacheDir a {@code File} indicating where the
! * cache file should be created, or {@code null} to use the
* system directory.
*
! * @return an {@code ImageInputStream} instance.
*
! * @exception IllegalArgumentException if {@code input} is
! * not an instance of the correct class or is {@code null}.
* @exception IllegalArgumentException if a cache file is needed
! * but {@code cacheDir} is non-{@code null} and is not a
* directory.
* @exception IOException if a cache file is needed but cannot be
* created.
*
* @see #getInputClass
*** 175,196 ****
createInputStreamInstance(Object input,
boolean useCache,
File cacheDir) throws IOException;
/**
! * Returns an instance of the <code>ImageInputStream</code>
* implementation associated with this service provider. A cache
* file will be created in the system-dependent default
* temporary-file directory, if needed.
*
* @param input an object of the class type returned by
! * <code>getInputClass</code>.
*
! * @return an <code>ImageInputStream</code> instance.
*
! * @exception IllegalArgumentException if <code>input</code> is
! * not an instance of the correct class or is <code>null</code>.
* @exception IOException if a cache file is needed but cannot be
* created.
*
* @see #getInputClass()
*/
--- 175,196 ----
createInputStreamInstance(Object input,
boolean useCache,
File cacheDir) throws IOException;
/**
! * Returns an instance of the {@code ImageInputStream}
* implementation associated with this service provider. A cache
* file will be created in the system-dependent default
* temporary-file directory, if needed.
*
* @param input an object of the class type returned by
! * {@code getInputClass}.
*
! * @return an {@code ImageInputStream} instance.
*
! * @exception IllegalArgumentException if {@code input} is
! * not an instance of the correct class or is {@code null}.
* @exception IOException if a cache file is needed but cannot be
* created.
*
* @see #getInputClass()
*/
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