ImageIO.java revision 0
/*
* Copyright 2000-2005 Sun Microsystems, Inc. All Rights Reserved.
* DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
*
* under the terms of the GNU General Public License version 2 only, as
* published by the Free Software Foundation. Sun designates this
* particular file as subject to the "Classpath" exception as provided
* by Sun in the LICENSE file that accompanied this code.
*
* This code is distributed in the hope that it will be useful, but WITHOUT
* ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
* FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License
* version 2 for more details (a copy is included in the LICENSE file that
* accompanied this code).
*
* You should have received a copy of the GNU General Public License version
* 2 along with this work; if not, write to the Free Software Foundation,
* Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA.
*
* Please contact Sun Microsystems, Inc., 4150 Network Circle, Santa Clara,
* CA 95054 USA or visit www.sun.com if you need additional information or
* have any questions.
*/
/**
* A class containing static convenience methods for locating
* <code>ImageReader</code>s and <code>ImageWriter</code>s, and
* performing simple encoding and decoding.
*
*/
public final class ImageIO {
private static final IIORegistry theRegistry =
/**
* Constructor is private to prevent instantiation.
*/
private ImageIO() {}
/**
* Scans for plug-ins on the application class path,
* loads their service provider classes, and registers a service
* provider instance for each one found with the
* <code>IIORegistry</code>.
*
* <p>This method is needed because the application class path can
* theoretically change, or additional plug-ins may become available.
* Rather than re-scanning the classpath on every invocation of the
* API, the class path is scanned automatically only on the first
* invocation. Clients can call this method to prompt a re-scan.
* Thus this method need only be invoked by sophisticated applications
* which dynamically make new plug-ins available at runtime.
*
* <p> The <code>getResources</code> method of the context
* <code>ClassLoader</code> is used locate JAR files containing
* files named
* <code>META-INF/services/javax.imageio.spi.</code><i>classname</i>,
* where <i>classname</i> is one of <code>ImageReaderSpi</code>,
* <code>ImageWriterSpi</code>, <code>ImageTranscoderSpi</code>,
* <code>ImageInputStreamSpi</code>, or
* <code>ImageOutputStreamSpi</code>, along the application class
* path.
*
* <p> The contents of the located files indicate the names of
* actual implementation classes which implement the
* aforementioned service provider interfaces; the default class
* loader is then used to load each of these classes and to
* instantiate an instance of each class, which is then placed
* into the registry for later retrieval.
*
* <p> The exact set of locations searched depends on the
* implementation of the Java runtime enviroment.
*
* @see ClassLoader#getResources
*/
public static void scanForPlugins() {
}
// ImageInputStreams
/**
* A class to hold information about caching. Each
* <code>ThreadGroup</code> will have its own copy
* via the <code>AppContext</code> mechanism.
*/
static class CacheInfo {
boolean useCache = true;
public CacheInfo() {}
public boolean getUseCache() {
return useCache;
}
public void setUseCache(boolean useCache) {
}
public File getCacheDirectory() {
return cacheDirectory;
}
this.cacheDirectory = cacheDirectory;
}
public Boolean getHasPermission() {
return hasPermission;
}
this.hasPermission = hasPermission;
}
}
/**
* Returns the <code>CacheInfo</code> object associated with this
* <code>ThreadGroup</code>.
*/
private static synchronized CacheInfo getCacheInfo() {
}
return info;
}
/**
* Returns the default temporary (cache) directory as defined by the
* java.io.tmpdir system property.
*/
private static String getTempDir() {
}
/**
* Determines whether the caller has write access to the cache
* directory, stores the result in the <code>CacheInfo</code> object,
* and returns the decision. This method helps to prevent mysterious
* SecurityExceptions to be thrown when this convenience class is used
* in an applet, for example.
*/
private static boolean hasCachePermission() {
if (hasPermission != null) {
return hasPermission.booleanValue();
} else {
try {
} else {
cachepath = getTempDir();
return false;
}
}
}
} catch (SecurityException e) {
return false;
}
return true;
}
}
/**
* Sets a flag indicating whether a disk-based cache file should
* be used when creating <code>ImageInputStream</code>s and
* <code>ImageOutputStream</code>s.
*
* <p> When reading from a standard <code>InputStream</code>>, it
* may be necessary to save previously read information in a cache
* since the underlying stream does not allow data to be re-read.
* Similarly, when writing to a standard
* <code>OutputStream</code>, a cache may be used to allow a
* previously written value to be changed before flushing it to
* the final destination.
*
* <p> The cache may reside in main memory or on disk. Setting
* this flag to <code>false</code> disallows the use of disk for
* future streams, which may be advantageous when working with
* small images, as the overhead of creating and destroying files
* is removed.
*
* <p> On startup, the value is set to <code>true</code>.
*
* @param useCache a <code>boolean</code> indicating whether a
* cache file should be used, in cases where it is optional.
*
* @see #getUseCache
*/
public static void setUseCache(boolean useCache) {
}
/**
* Returns the current value set by <code>setUseCache</code>, or
* <code>true</code> if no explicit setting has been made.
*
* @return true if a disk-based cache may be used for
* <code>ImageInputStream</code>s and
* <code>ImageOutputStream</code>s.
*
* @see #setUseCache
*/
public static boolean getUseCache() {
return getCacheInfo().getUseCache();
}
/**
* Sets the directory where cache files are to be created. A
* value of <code>null</code> indicates that the system-dependent
* default temporary-file directory is to be used. If
* <code>getUseCache</code> returns false, this value is ignored.
*
* @param cacheDirectory a <code>File</code> specifying a directory.
*
* @see File#createTempFile(String, String, File)
*
* @exception SecurityException if the security manager denies
* access to the directory.
* @exception IllegalArgumentException if <code>cacheDir</code> is
* non-<code>null</code> but is not a directory.
*
* @see #getCacheDirectory
*/
throw new IllegalArgumentException("Not a directory!");
}
}
/**
* Returns the current value set by
* <code>setCacheDirectory</code>, or <code>null</code> if no
* explicit setting has been made.
*
* @return a <code>File</code> indicating the directory where
* cache files will be created, or <code>null</code> to indicate
* the system-dependent default temporary-file directory.
*
* @see #setCacheDirectory
*/
public static File getCacheDirectory() {
return getCacheInfo().getCacheDirectory();
}
/**
* Returns an <code>ImageInputStream</code> that will take its
* input from the given <code>Object</code>. The set of
* <code>ImageInputStreamSpi</code>s registered with the
* <code>IIORegistry</code> class is queried and the first one
* that is able to take input from the supplied object is used to
* create the returned <code>ImageInputStream</code>. If no
* suitable <code>ImageInputStreamSpi</code> exists,
* <code>null</code> is returned.
*
* <p> The current cache settings from <code>getUseCache</code>and
* <code>getCacheDirectory</code> will be used to control caching.
*
* @param input an <code>Object</code> to be used as an input
* source, such as a <code>File</code>, readable
* <code>RandomAccessFile</code>, or <code>InputStream</code>.
*
* @return an <code>ImageInputStream</code>, or <code>null</code>.
*
* @exception IllegalArgumentException if <code>input</code>
* is <code>null</code>.
* @exception IOException if a cache file is needed but cannot be
* created.
*
* @see javax.imageio.spi.ImageInputStreamSpi
*/
throws IOException {
throw new IllegalArgumentException("input == null!");
}
// Ensure category is present
try {
true);
} catch (IllegalArgumentException e) {
return null;
}
try {
} catch (IOException e) {
throw new IIOException("Can't create cache file!", e);
}
}
}
return null;
}
// ImageOutputStreams
/**
* Returns an <code>ImageOutputStream</code> that will send its
* output to the given <code>Object</code>. The set of
* <code>ImageOutputStreamSpi</code>s registered with the
* <code>IIORegistry</code> class is queried and the first one
* that is able to send output from the supplied object is used to
* create the returned <code>ImageOutputStream</code>. If no
* suitable <code>ImageOutputStreamSpi</code> exists,
* <code>null</code> is returned.
*
* <p> The current cache settings from <code>getUseCache</code>and
* <code>getCacheDirectory</code> will be used to control caching.
*
* @param output an <code>Object</code> to be used as an output
* destination, such as a <code>File</code>, writable
* <code>RandomAccessFile</code>, or <code>OutputStream</code>.
*
* @return an <code>ImageOutputStream</code>, or
* <code>null</code>.
*
* @exception IllegalArgumentException if <code>output</code> is
* <code>null</code>.
* @exception IOException if a cache file is needed but cannot be
* created.
*
* @see javax.imageio.spi.ImageOutputStreamSpi
*/
throws IOException {
throw new IllegalArgumentException("output == null!");
}
// Ensure category is present
try {
true);
} catch (IllegalArgumentException e) {
return null;
}
try {
} catch (IOException e) {
throw new IIOException("Can't create cache file!", e);
}
}
}
return null;
}
private static enum SpiInfo {
return spi.getFormatNames();
}
},
return spi.getMIMETypes();
}
},
return spi.getFileSuffixes();
}
};
}
private static <S extends ImageReaderWriterSpi>
{
// Ensure category is present
try {
} catch (IllegalArgumentException e) {
return new String[0];
}
}
}
// Readers
/**
* Returns an array of <code>String</code>s listing all of the
* informal format names understood by the current set of registered
* readers.
*
* @return an array of <code>String</code>s.
*/
public static String[] getReaderFormatNames() {
return getReaderWriterInfo(ImageReaderSpi.class,
}
/**
* Returns an array of <code>String</code>s listing all of the
* MIME types understood by the current set of registered
* readers.
*
* @return an array of <code>String</code>s.
*/
public static String[] getReaderMIMETypes() {
return getReaderWriterInfo(ImageReaderSpi.class,
}
/**
* Returns an array of <code>String</code>s listing all of the
* file suffixes associated with the formats understood
* by the current set of registered readers.
*
* @return an array of <code>String</code>s.
* @since 1.6
*/
public static String[] getReaderFileSuffixes() {
return getReaderWriterInfo(ImageReaderSpi.class,
}
// Contains ImageReaderSpis
}
public boolean hasNext() {
}
public ImageReader next() {
try {
return spi.createReaderInstance();
} catch (IOException e) {
// Deregister the spi in this case, but only as
// an ImageReaderSpi
}
return null;
}
public void remove() {
throw new UnsupportedOperationException();
}
}
static class CanDecodeInputFilter
implements ServiceRegistry.Filter {
}
try {
if (input instanceof ImageInputStream) {
}
// even though plug-ins are supposed to take
// care of it.
boolean canDecode = false;
}
}
return canDecode;
} catch (IOException e) {
return false;
}
}
}
static class CanEncodeImageAndFormatFilter
implements ServiceRegistry.Filter {
String formatName) {
this.formatName = formatName;
}
}
}
static class ContainsFilter
implements ServiceRegistry.Filter {
// method returns an array of Strings
}
try {
} catch (Exception e) {
return false;
}
}
}
/**
* Returns an <code>Iterator</code> containing all currently
* registered <code>ImageReader</code>s that claim to be able to
* decode the supplied <code>Object</code>, typically an
* <code>ImageInputStream</code>.
*
* <p> The stream position is left at its prior position upon
* exit from this method.
*
* @param input an <code>ImageInputStream</code> or other
* <code>Object</code> containing encoded image data.
*
* @return an <code>Iterator</code> containing <code>ImageReader</code>s.
*
* @exception IllegalArgumentException if <code>input</code> is
* <code>null</code>.
*
* @see javax.imageio.spi.ImageReaderSpi#canDecodeInput
*/
throw new IllegalArgumentException("input == null!");
}
// Ensure category is present
try {
new CanDecodeInputFilter(input),
true);
} catch (IllegalArgumentException e) {
return Collections.emptyIterator();
}
return new ImageReaderIterator(iter);
}
private static Method readerFormatNamesMethod;
private static Method readerFileSuffixesMethod;
private static Method readerMIMETypesMethod;
private static Method writerFormatNamesMethod;
private static Method writerFileSuffixesMethod;
private static Method writerMIMETypesMethod;
static {
try {
} catch (NoSuchMethodException e) {
e.printStackTrace();
}
}
/**
* Returns an <code>Iterator</code> containing all currently
* registered <code>ImageReader</code>s that claim to be able to
* decode the named format.
*
* @param formatName a <code>String</code> containing the informal
* name of a format (<i>e.g.</i>, "jpeg" or "tiff".
*
* @return an <code>Iterator</code> containing
* <code>ImageReader</code>s.
*
* @exception IllegalArgumentException if <code>formatName</code>
* is <code>null</code>.
*
* @see javax.imageio.spi.ImageReaderSpi#getFormatNames
*/
public static Iterator<ImageReader>
{
if (formatName == null) {
throw new IllegalArgumentException("formatName == null!");
}
// Ensure category is present
try {
true);
} catch (IllegalArgumentException e) {
return Collections.emptyIterator();
}
return new ImageReaderIterator(iter);
}
/**
* Returns an <code>Iterator</code> containing all currently
* registered <code>ImageReader</code>s that claim to be able to
* decode files with the given suffix.
*
* @param fileSuffix a <code>String</code> containing a file
* suffix (<i>e.g.</i>, "jpg" or "tiff").
*
* @return an <code>Iterator</code> containing
* <code>ImageReader</code>s.
*
* @exception IllegalArgumentException if <code>fileSuffix</code>
* is <code>null</code>.
*
* @see javax.imageio.spi.ImageReaderSpi#getFileSuffixes
*/
public static Iterator<ImageReader>
{
if (fileSuffix == null) {
throw new IllegalArgumentException("fileSuffix == null!");
}
// Ensure category is present
try {
true);
} catch (IllegalArgumentException e) {
return Collections.emptyIterator();
}
return new ImageReaderIterator(iter);
}
/**
* Returns an <code>Iterator</code> containing all currently
* registered <code>ImageReader</code>s that claim to be able to
* decode files with the given MIME type.
*
* @param MIMEType a <code>String</code> containing a file
*
* @return an <code>Iterator</code> containing
* <code>ImageReader</code>s.
*
* @exception IllegalArgumentException if <code>MIMEType</code> is
* <code>null</code>.
*
* @see javax.imageio.spi.ImageReaderSpi#getMIMETypes
*/
public static Iterator<ImageReader>
{
throw new IllegalArgumentException("MIMEType == null!");
}
// Ensure category is present
try {
MIMEType),
true);
} catch (IllegalArgumentException e) {
return Collections.emptyIterator();
}
return new ImageReaderIterator(iter);
}
// Writers
/**
* Returns an array of <code>String</code>s listing all of the
* informal format names understood by the current set of registered
* writers.
*
* @return an array of <code>String</code>s.
*/
public static String[] getWriterFormatNames() {
return getReaderWriterInfo(ImageWriterSpi.class,
}
/**
* Returns an array of <code>String</code>s listing all of the
* MIME types understood by the current set of registered
* writers.
*
* @return an array of <code>String</code>s.
*/
public static String[] getWriterMIMETypes() {
return getReaderWriterInfo(ImageWriterSpi.class,
}
/**
* Returns an array of <code>String</code>s listing all of the
* file suffixes associated with the formats understood
* by the current set of registered writers.
*
* @return an array of <code>String</code>s.
* @since 1.6
*/
public static String[] getWriterFileSuffixes() {
return getReaderWriterInfo(ImageWriterSpi.class,
}
// Contains ImageWriterSpis
}
public boolean hasNext() {
}
public ImageWriter next() {
try {
return spi.createWriterInstance();
} catch (IOException e) {
// Deregister the spi in this case, but only as a writerSpi
}
return null;
}
public void remove() {
throw new UnsupportedOperationException();
}
}
return true;
}
}
return false;
}
/**
* Returns an <code>Iterator</code> containing all currently
* registered <code>ImageWriter</code>s that claim to be able to
* encode the named format.
*
* @param formatName a <code>String</code> containing the informal
* name of a format (<i>e.g.</i>, "jpeg" or "tiff".
*
* @return an <code>Iterator</code> containing
* <code>ImageWriter</code>s.
*
* @exception IllegalArgumentException if <code>formatName</code> is
* <code>null</code>.
*
* @see javax.imageio.spi.ImageWriterSpi#getFormatNames
*/
public static Iterator<ImageWriter>
{
if (formatName == null) {
throw new IllegalArgumentException("formatName == null!");
}
// Ensure category is present
try {
true);
} catch (IllegalArgumentException e) {
return Collections.emptyIterator();
}
return new ImageWriterIterator(iter);
}
/**
* Returns an <code>Iterator</code> containing all currently
* registered <code>ImageWriter</code>s that claim to be able to
* encode files with the given suffix.
*
* @param fileSuffix a <code>String</code> containing a file
* suffix (<i>e.g.</i>, "jpg" or "tiff").
*
* @return an <code>Iterator</code> containing <code>ImageWriter</code>s.
*
* @exception IllegalArgumentException if <code>fileSuffix</code> is
* <code>null</code>.
*
* @see javax.imageio.spi.ImageWriterSpi#getFileSuffixes
*/
public static Iterator<ImageWriter>
{
if (fileSuffix == null) {
throw new IllegalArgumentException("fileSuffix == null!");
}
// Ensure category is present
try {
true);
} catch (IllegalArgumentException e) {
return Collections.emptyIterator();
}
return new ImageWriterIterator(iter);
}
/**
* Returns an <code>Iterator</code> containing all currently
* registered <code>ImageWriter</code>s that claim to be able to
* encode files with the given MIME type.
*
* @param MIMEType a <code>String</code> containing a file
*
* @return an <code>Iterator</code> containing <code>ImageWriter</code>s.
*
* @exception IllegalArgumentException if <code>MIMEType</code> is
* <code>null</code>.
*
* @see javax.imageio.spi.ImageWriterSpi#getMIMETypes
*/
public static Iterator<ImageWriter>
{
throw new IllegalArgumentException("MIMEType == null!");
}
// Ensure category is present
try {
MIMEType),
true);
} catch (IllegalArgumentException e) {
return Collections.emptyIterator();
}
return new ImageWriterIterator(iter);
}
/**
* Returns an <code>ImageWriter</code>corresponding to the given
* <code>ImageReader</code>, if there is one, or <code>null</code>
* if the plug-in for this <code>ImageReader</code> does not
* specify a corresponding <code>ImageWriter</code>, or if the
* given <code>ImageReader</code> is not registered. This
* mechanism may be used to obtain an <code>ImageWriter</code>
* that will understand the internal structure of non-pixel
* metadata (as encoded by <code>IIOMetadata</code> objects)
* generated by the <code>ImageReader</code>. By obtaining this
* data from the <code>ImageReader</code> and passing it on to the
* <code>ImageWriter</code> obtained with this method, a client
* program can read an image, modify it in some way, and write it
* back out preserving all metadata, without having to understand
* anything about the structure of the metadata, or even about
* the image format. Note that this method returns the
* "preferred" writer, which is the first in the list returned by
* <code>javax.imageio.spi.ImageReaderSpi.getImageWriterSpiNames()</code>.
*
* @param reader an instance of a registered <code>ImageReader</code>.
*
* @return an <code>ImageWriter</code>, or null.
*
* @exception IllegalArgumentException if <code>reader</code> is
* <code>null</code>.
*
* @see #getImageReader(ImageWriter)
* @see javax.imageio.spi.ImageReaderSpi#getImageWriterSpiNames()
*/
throw new IllegalArgumentException("reader == null!");
}
// Ensure category is present
try {
false);
} catch (IllegalArgumentException e) {
return null;
}
while (readerSpiIter.hasNext()) {
break;
}
}
return null;
}
}
if (writerNames == null) {
return null;
}
try {
} catch (ClassNotFoundException e) {
return null;
}
return null;
}
try {
return writerSpi.createWriterInstance();
} catch (IOException e) {
// Deregister the spi in this case, but only as a writerSpi
ImageWriterSpi.class);
return null;
}
}
/**
* Returns an <code>ImageReader</code>corresponding to the given
* <code>ImageWriter</code>, if there is one, or <code>null</code>
* if the plug-in for this <code>ImageWriter</code> does not
* specify a corresponding <code>ImageReader</code>, or if the
* given <code>ImageWriter</code> is not registered. This method
* is provided principally for symmetry with
* <code>getImageWriter(ImageReader)</code>. Note that this
* method returns the "preferred" reader, which is the first in
* the list returned by
* javax.imageio.spi.ImageWriterSpi.<code>getImageReaderSpiNames()</code>.
*
* @param writer an instance of a registered <code>ImageWriter</code>.
*
* @return an <code>ImageReader</code>, or null.
*
* @exception IllegalArgumentException if <code>writer</code> is
* <code>null</code>.
*
* @see #getImageWriter(ImageReader)
* @see javax.imageio.spi.ImageWriterSpi#getImageReaderSpiNames()
*/
throw new IllegalArgumentException("writer == null!");
}
// Ensure category is present
try {
false);
} catch (IllegalArgumentException e) {
return null;
}
while (writerSpiIter.hasNext()) {
break;
}
}
return null;
}
}
if (readerNames == null) {
return null;
}
try {
} catch (ClassNotFoundException e) {
return null;
}
return null;
}
try {
return readerSpi.createReaderInstance();
} catch (IOException e) {
// Deregister the spi in this case, but only as a readerSpi
ImageReaderSpi.class);
return null;
}
}
/**
* Returns an <code>Iterator</code> containing all currently
* registered <code>ImageWriter</code>s that claim to be able to
* encode images of the given layout (specified using an
* <code>ImageTypeSpecifier</code>) in the given format.
*
* @param type an <code>ImageTypeSpecifier</code> indicating the
* layout of the image to be written.
* @param formatName the informal name of the <code>format</code>.
*
* @return an <code>Iterator</code> containing <code>ImageWriter</code>s.
*
* @exception IllegalArgumentException if any parameter is
* <code>null</code>.
*
* @see javax.imageio.spi.ImageWriterSpi#canEncodeImage(ImageTypeSpecifier)
*/
public static Iterator<ImageWriter>
{
throw new IllegalArgumentException("type == null!");
}
if (formatName == null) {
throw new IllegalArgumentException("formatName == null!");
}
// Ensure category is present
try {
true);
} catch (IllegalArgumentException e) {
return Collections.emptyIterator();
}
return new ImageWriterIterator(iter);
}
static class ImageTranscoderIterator
implements Iterator<ImageTranscoder>
{
// Contains ImageTranscoderSpis
}
public boolean hasNext() {
}
public ImageTranscoder next() {
return spi.createTranscoderInstance();
}
public void remove() {
throw new UnsupportedOperationException();
}
}
static class TranscoderFilter
implements ServiceRegistry.Filter {
}
}
}
/**
* Returns an <code>Iterator</code> containing all currently
* registered <code>ImageTranscoder</code>s that claim to be
* able to transcode between the metadata of the given
* <code>ImageReader</code> and <code>ImageWriter</code>.
*
* @param reader an <code>ImageReader</code>.
* @param writer an <code>ImageWriter</code>.
*
* @return an <code>Iterator</code> containing
* <code>ImageTranscoder</code>s.
*
* @exception IllegalArgumentException if <code>reader</code> or
* <code>writer</code> is <code>null</code>.
*/
public static Iterator<ImageTranscoder>
{
throw new IllegalArgumentException("reader == null!");
}
throw new IllegalArgumentException("writer == null!");
}
// Ensure category is present
try {
filter, true);
} catch (IllegalArgumentException e) {
return Collections.emptyIterator();
}
return new ImageTranscoderIterator(iter);
}
// All-in-one methods
/**
* Returns a <code>BufferedImage</code> as the result of decoding
* a supplied <code>File</code> with an <code>ImageReader</code>
* chosen automatically from among those currently registered.
* The <code>File</code> is wrapped in an
* <code>ImageInputStream</code>. If no registered
* <code>ImageReader</code> claims to be able to read the
* resulting stream, <code>null</code> is returned.
*
* <p> The current cache settings from <code>getUseCache</code>and
* <code>getCacheDirectory</code> will be used to control caching in the
* <code>ImageInputStream</code> that is created.
*
* <p> Note that there is no <code>read</code> method that takes a
* filename as a <code>String</code>; use this method instead after
* creating a <code>File</code> from the filename.
*
* <p> This method does not attempt to locate
* <code>ImageReader</code>s that can read directly from a
* <code>File</code>; that may be accomplished using
* <code>IIORegistry</code> and <code>ImageReaderSpi</code>.
*
* @param input a <code>File</code> to read from.
*
* @return a <code>BufferedImage</code> containing the decoded
* contents of the input, or <code>null</code>.
*
* @exception IllegalArgumentException if <code>input</code> is
* <code>null</code>.
* @exception IOException if an error occurs during reading.
*/
throw new IllegalArgumentException("input == null!");
}
throw new IIOException("Can't read input file!");
}
throw new IIOException("Can't create an ImageInputStream!");
}
}
return bi;
}
/**
* Returns a <code>BufferedImage</code> as the result of decoding
* a supplied <code>InputStream</code> with an <code>ImageReader</code>
* chosen automatically from among those currently registered.
* The <code>InputStream</code> is wrapped in an
* <code>ImageInputStream</code>. If no registered
* <code>ImageReader</code> claims to be able to read the
* resulting stream, <code>null</code> is returned.
*
* <p> The current cache settings from <code>getUseCache</code>and
* <code>getCacheDirectory</code> will be used to control caching in the
* <code>ImageInputStream</code> that is created.
*
* <p> This method does not attempt to locate
* <code>ImageReader</code>s that can read directly from an
* <code>InputStream</code>; that may be accomplished using
* <code>IIORegistry</code> and <code>ImageReaderSpi</code>.
*
* <p> This method <em>does not</em> close the provided
* <code>InputStream</code> after the read operation has completed;
* it is the responsibility of the caller to close the stream, if desired.
*
* @param input an <code>InputStream</code> to read from.
*
* @return a <code>BufferedImage</code> containing the decoded
* contents of the input, or <code>null</code>.
*
* @exception IllegalArgumentException if <code>input</code> is
* <code>null</code>.
* @exception IOException if an error occurs during reading.
*/
throw new IllegalArgumentException("input == null!");
}
}
return bi;
}
/**
* Returns a <code>BufferedImage</code> as the result of decoding
* a supplied <code>URL</code> with an <code>ImageReader</code>
* chosen automatically from among those currently registered. An
* <code>InputStream</code> is obtained from the <code>URL</code>,
* which is wrapped in an <code>ImageInputStream</code>. If no
* registered <code>ImageReader</code> claims to be able to read
* the resulting stream, <code>null</code> is returned.
*
* <p> The current cache settings from <code>getUseCache</code>and
* <code>getCacheDirectory</code> will be used to control caching in the
* <code>ImageInputStream</code> that is created.
*
* <p> This method does not attempt to locate
* <code>ImageReader</code>s that can read directly from a
* <code>URL</code>; that may be accomplished using
* <code>IIORegistry</code> and <code>ImageReaderSpi</code>.
*
* @param input a <code>URL</code> to read from.
*
* @return a <code>BufferedImage</code> containing the decoded
* contents of the input, or <code>null</code>.
*
* @exception IllegalArgumentException if <code>input</code> is
* <code>null</code>.
* @exception IOException if an error occurs during reading.
*/
throw new IllegalArgumentException("input == null!");
}
try {
} catch (IOException e) {
throw new IIOException("Can't get input stream from URL!", e);
}
try {
}
} finally {
}
return bi;
}
/**
* Returns a <code>BufferedImage</code> as the result of decoding
* a supplied <code>ImageInputStream</code> with an
* <code>ImageReader</code> chosen automatically from among those
* currently registered. If no registered
* <code>ImageReader</code> claims to be able to read the stream,
* <code>null</code> is returned.
*
* <p> Unlike most other methods in this class, this method <em>does</em>
* close the provided <code>ImageInputStream</code> after the read
* operation has completed, unless <code>null</code> is returned,
* in which case this method <em>does not</em> close the stream.
*
* @param stream an <code>ImageInputStream</code> to read from.
*
* @return a <code>BufferedImage</code> containing the decoded
* contents of the input, or <code>null</code>.
*
* @exception IllegalArgumentException if <code>stream</code> is
* <code>null</code>.
* @exception IOException if an error occurs during reading.
*/
throws IOException {
throw new IllegalArgumentException("stream == null!");
}
return null;
}
try {
} finally {
}
return bi;
}
/**
* Writes an image using the an arbitrary <code>ImageWriter</code>
* that supports the given format to an
* <code>ImageOutputStream</code>. The image is written to the
* <code>ImageOutputStream</code> starting at the current stream
* pointer, overwriting existing stream data from that point
* forward, if present.
*
* <p> This method <em>does not</em> close the provided
* <code>ImageOutputStream</code> after the write operation has completed;
* it is the responsibility of the caller to close the stream, if desired.
*
* @param im a <code>RenderedImage</code> to be written.
* @param formatName a <code>String</code> containg the informal
* name of the format.
* @param output an <code>ImageOutputStream</code> to be written to.
*
* @return <code>false</code> if no appropriate writer is found.
*
* @exception IllegalArgumentException if any parameter is
* <code>null</code>.
* @exception IOException if an error occurs during writing.
*/
throw new IllegalArgumentException("im == null!");
}
if (formatName == null) {
throw new IllegalArgumentException("formatName == null!");
}
throw new IllegalArgumentException("output == null!");
}
}
/**
* Writes an image using an arbitrary <code>ImageWriter</code>
* that supports the given format to a <code>File</code>. If
* there is already a <code>File</code> present, its contents are
* discarded.
*
* @param im a <code>RenderedImage</code> to be written.
* @param formatName a <code>String</code> containg the informal
* name of the format.
* @param output a <code>File</code> to be written to.
*
* @return <code>false</code> if no appropriate writer is found.
*
* @exception IllegalArgumentException if any parameter is
* <code>null</code>.
* @exception IOException if an error occurs during writing.
*/
throw new IllegalArgumentException("output == null!");
}
/* Do not make changes in the file system if we have
* no appropriate writer.
*/
return false;
}
try {
} catch (IOException e) {
throw new IIOException("Can't create output stream!", e);
}
try {
} finally {
}
}
/**
* Writes an image using an arbitrary <code>ImageWriter</code>
* that supports the given format to an <code>OutputStream</code>.
*
* <p> This method <em>does not</em> close the provided
* <code>OutputStream</code> after the write operation has completed;
* it is the responsibility of the caller to close the stream, if desired.
*
* <p> The current cache settings from <code>getUseCache</code>and
* <code>getCacheDirectory</code> will be used to control caching.
*
* @param im a <code>RenderedImage</code> to be written.
* @param formatName a <code>String</code> containg the informal
* name of the format.
* @param output an <code>OutputStream</code> to be written to.
*
* @return <code>false</code> if no appropriate writer is found.
*
* @exception IllegalArgumentException if any parameter is
* <code>null</code>.
* @exception IOException if an error occurs during writing.
*/
throw new IllegalArgumentException("output == null!");
}
try {
} catch (IOException e) {
throw new IIOException("Can't create output stream!", e);
}
try {
} finally {
}
}
/**
* Returns <code>ImageWriter</code> instance according to given
* rendered image and image format or <code>null</code> if there
* is no appropriate writer.
*/
String formatName) {
} else {
return null;
}
}
/**
* Writes image to output stream using given image writer.
*/
return false;
}
try {
} finally {
}
return true;
}
}