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META-INF.modules.java.desktop.classes.javax.imageio.spi.ImageReaderWriterSpi Maven / Gradle / Ivy

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 * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
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 * This code is free software; you can redistribute it and/or modify it
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 * published by the Free Software Foundation.  Oracle designates this
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 * by Oracle in the LICENSE file that accompanied this code.
 *
 * This code is distributed in the hope that it will be useful, but WITHOUT
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 * 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).
 *
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package javax.imageio.spi;

import java.io.IOException;
import java.lang.reflect.Constructor;
import java.lang.reflect.Method;
import java.security.AccessController;
import java.security.PrivilegedAction;
import java.util.Arrays;
import java.util.Iterator;
import javax.imageio.ImageReader;
import javax.imageio.metadata.IIOMetadata;
import javax.imageio.metadata.IIOMetadataFormat;
import javax.imageio.metadata.IIOMetadataFormatImpl;
import javax.imageio.stream.ImageInputStream;

/**
 * A superclass containing instance variables and methods common to
 * {@code ImageReaderSpi} and {@code ImageWriterSpi}.
 *
 * @see IIORegistry
 * @see ImageReaderSpi
 * @see ImageWriterSpi
 *
 */
public abstract class ImageReaderWriterSpi extends IIOServiceProvider {

    /**
     * An array of strings to be returned from
     * {@code getFormatNames}, initially {@code null}.
     * Constructors should set this to a non-{@code null} value.
     */
    protected String[] names = null;

    /**
     * An array of strings to be returned from
     * {@code getFileSuffixes}, initially {@code null}.
     */
    protected String[] suffixes = null;

    /**
     * An array of strings to be returned from
     * {@code getMIMETypes}, initially {@code null}.
     */
    protected String[] MIMETypes = null;

    /**
     * A {@code String} containing the name of the associated
     * plug-in class, initially {@code null}.
     */
    protected String pluginClassName = null;

    /**
     * A boolean indicating whether this plug-in supports the
     * standard metadata format for stream metadata, initially
     * {@code false}.
     */
    protected boolean supportsStandardStreamMetadataFormat = false;

    /**
     * A {@code String} containing the name of the native stream
     * metadata format supported by this plug-in, initially
     * {@code null}.
     */
    protected String nativeStreamMetadataFormatName = null;

    /**
     * A {@code String} containing the class name of the native
     * stream metadata format supported by this plug-in, initially
     * {@code null}.
     */
    protected String nativeStreamMetadataFormatClassName = null;

    /**
     * An array of {@code String}s containing the names of any
     * additional stream metadata formats supported by this plug-in,
     * initially {@code null}.
     */
    protected String[] extraStreamMetadataFormatNames = null;

    /**
     * An array of {@code String}s containing the class names of
     * any additional stream metadata formats supported by this plug-in,
     * initially {@code null}.
     */
    protected String[] extraStreamMetadataFormatClassNames = null;

    /**
     * A boolean indicating whether this plug-in supports the
     * standard metadata format for image metadata, initially
     * {@code false}.
     */
    protected boolean supportsStandardImageMetadataFormat = false;

    /**
     * A {@code String} containing the name of the
     * native stream metadata format supported by this plug-in,
     * initially {@code null}.
     */
    protected String nativeImageMetadataFormatName = null;

    /**
     * A {@code String} containing the class name of the
     * native stream metadata format supported by this plug-in,
     * initially {@code null}.
     */
    protected String nativeImageMetadataFormatClassName = null;

    /**
     * An array of {@code String}s containing the names of any
     * additional image metadata formats supported by this plug-in,
     * initially {@code null}.
     */
    protected String[] extraImageMetadataFormatNames = null;

    /**
     * An array of {@code String}s containing the class names of
     * any additional image metadata formats supported by this
     * plug-in, initially {@code null}.
     */
    protected String[] extraImageMetadataFormatClassNames = null;

    /**
     * Constructs an {@code ImageReaderWriterSpi} with a given
     * set of values.
     *
     * @param vendorName the vendor name, as a non-{@code null}
     * {@code String}.
     * @param version a version identifier, as a non-{@code null}
     * {@code String}.
     * @param names a non-{@code null} array of
     * {@code String}s indicating the format names.  At least one
     * entry must be present.
     * @param suffixes an array of {@code String}s indicating the
     * common file suffixes.  If no suffixes are defined,
     * {@code null} should be supplied.  An array of length 0
     * will be normalized to {@code null}.
     * @param MIMETypes an array of {@code String}s indicating
     * the format's MIME types.  If no MIME types are defined,
     * {@code null} should be supplied.  An array of length 0
     * will be normalized to {@code null}.
     * @param pluginClassName the fully-qualified name of the
     * associated {@code ImageReader} or {@code ImageWriter}
     * class, as a non-{@code null String}.
     * @param supportsStandardStreamMetadataFormat a
     * {@code boolean} that indicates whether a stream metadata
     * object can use trees described by the standard metadata format.
     * @param nativeStreamMetadataFormatName a
     * {@code String}, or {@code null}, to be returned from
     * {@code getNativeStreamMetadataFormatName}.
     * @param nativeStreamMetadataFormatClassName a
     * {@code String}, or {@code null}, to be used to instantiate
     * a metadata format object to be returned from
     * {@code getNativeStreamMetadataFormat}.
     * @param extraStreamMetadataFormatNames an array of
     * {@code String}s, or {@code null}, to be returned from
     * {@code getExtraStreamMetadataFormatNames}.  An array of length
     * 0 is normalized to {@code null}.
     * @param extraStreamMetadataFormatClassNames an array of
     * {@code String}s, or {@code null}, to be used to instantiate
     * a metadata format object to be returned from
     * {@code getStreamMetadataFormat}.  An array of length
     * 0 is normalized to {@code null}.
     * @param supportsStandardImageMetadataFormat a
     * {@code boolean} that indicates whether an image metadata
     * object can use trees described by the standard metadata format.
     * @param nativeImageMetadataFormatName a
     * {@code String}, or {@code null}, to be returned from
     * {@code getNativeImageMetadataFormatName}.
     * @param nativeImageMetadataFormatClassName a
     * {@code String}, or {@code null}, to be used to instantiate
     * a metadata format object to be returned from
     * {@code getNativeImageMetadataFormat}.
     * @param extraImageMetadataFormatNames an array of
     * {@code String}s to be returned from
     * {@code getExtraImageMetadataFormatNames}.  An array of length 0
     * is normalized to {@code null}.
     * @param extraImageMetadataFormatClassNames an array of
     * {@code String}s, or {@code null}, to be used to instantiate
     * a metadata format object to be returned from
     * {@code getImageMetadataFormat}.  An array of length
     * 0 is normalized to {@code null}.
     *
     * @exception IllegalArgumentException if {@code vendorName}
     * is {@code null}.
     * @exception IllegalArgumentException if {@code version}
     * is {@code null}.
     * @exception IllegalArgumentException if {@code names}
     * is {@code null} or has length 0.
     * @exception IllegalArgumentException if {@code pluginClassName}
     * is {@code null}.
     */
    public ImageReaderWriterSpi(String vendorName,
                                String version,
                                String[] names,
                                String[] suffixes,
                                String[] MIMETypes,
                                String pluginClassName,
                                boolean supportsStandardStreamMetadataFormat,
                                String nativeStreamMetadataFormatName,
                                String nativeStreamMetadataFormatClassName,
                                String[] extraStreamMetadataFormatNames,
                                String[] extraStreamMetadataFormatClassNames,
                                boolean supportsStandardImageMetadataFormat,
                                String nativeImageMetadataFormatName,
                                String nativeImageMetadataFormatClassName,
                                String[] extraImageMetadataFormatNames,
                                String[] extraImageMetadataFormatClassNames) {
        super(vendorName, version);
        if (names == null) {
            throw new IllegalArgumentException("names == null!");
        }
        if (names.length == 0) {
            throw new IllegalArgumentException("names.length == 0!");
        }
        if (pluginClassName == null) {
            throw new IllegalArgumentException("pluginClassName == null!");
        }

        this.names = names.clone();
        // If length == 0, leave it null
        if (suffixes != null && suffixes.length > 0) {
            this.suffixes = suffixes.clone();
        }
        // If length == 0, leave it null
        if (MIMETypes != null && MIMETypes.length > 0) {
            this.MIMETypes = MIMETypes.clone();
        }
        this.pluginClassName = pluginClassName;

        this.supportsStandardStreamMetadataFormat =
            supportsStandardStreamMetadataFormat;
        this.nativeStreamMetadataFormatName = nativeStreamMetadataFormatName;
        this.nativeStreamMetadataFormatClassName =
            nativeStreamMetadataFormatClassName;
        // If length == 0, leave it null
        if (extraStreamMetadataFormatNames != null &&
            extraStreamMetadataFormatNames.length > 0) {
            this.extraStreamMetadataFormatNames =
                extraStreamMetadataFormatNames.clone();
        }
        // If length == 0, leave it null
        if (extraStreamMetadataFormatClassNames != null &&
            extraStreamMetadataFormatClassNames.length > 0) {
            this.extraStreamMetadataFormatClassNames =
                extraStreamMetadataFormatClassNames.clone();
        }
        this.supportsStandardImageMetadataFormat =
            supportsStandardImageMetadataFormat;
        this.nativeImageMetadataFormatName = nativeImageMetadataFormatName;
        this.nativeImageMetadataFormatClassName =
            nativeImageMetadataFormatClassName;
        // If length == 0, leave it null
        if (extraImageMetadataFormatNames != null &&
            extraImageMetadataFormatNames.length > 0) {
            this.extraImageMetadataFormatNames =
                extraImageMetadataFormatNames.clone();
        }
        // If length == 0, leave it null
        if (extraImageMetadataFormatClassNames != null &&
            extraImageMetadataFormatClassNames.length > 0) {
            this.extraImageMetadataFormatClassNames =
                extraImageMetadataFormatClassNames.clone();
        }
    }

    /**
     * Constructs a blank {@code ImageReaderWriterSpi}.  It is up
     * to the subclass to initialize instance variables and/or
     * override method implementations in order to provide working
     * versions of all methods.
     */
    public ImageReaderWriterSpi() {
    }

    /**
     * Returns an array of {@code String}s containing
     * human-readable names for the formats that are generally usable
     * by the {@code ImageReader} or {@code ImageWriter}
     * implementation associated with this service provider.  For
     * example, a single {@code ImageReader} might be able to
     * process both PBM and PNM files.
     *
     * @return a non-{@code null} array of {@code String}s
     * or length at least 1 containing informal format names
     * associated with this reader or writer.
     */
    public String[] getFormatNames() {
        return names.clone();
    }

    /**
     * Returns an array of {@code String}s containing a list of
     * file suffixes associated with the formats that are generally
     * usable by the {@code ImageReader} or
     * {@code ImageWriter} implementation associated with this
     * service provider.  For example, a single
     * {@code ImageReader} might be able to process files with
     * '.pbm' and '.pnm' suffixes, or both '.jpg' and '.jpeg'
     * suffixes.  If there are no known file suffixes,
     * {@code null} will be returned.
     *
     * 

Returning a particular suffix does not guarantee that files * with that suffix can be processed; it merely indicates that it * may be worthwhile attempting to decode or encode such files * using this service provider. * * @return an array of {@code String}s or length at least 1 * containing common file suffixes associated with this reader or * writer, or {@code null}. */ public String[] getFileSuffixes() { return suffixes == null ? null : suffixes.clone(); } /** * Returns an array of {@code String}s containing a list of * MIME types associated with the formats that are generally * usable by the {@code ImageReader} or * {@code ImageWriter} implementation associated with this * service provider. * *

Ideally, only a single MIME type would be required in order * to describe a particular format. However, for several reasons * it is necessary to associate a list of types with each service * provider. First, many common image file formats do not have * standard MIME types, so a list of commonly used unofficial * names will be required, such as {@code image/x-pbm} and * {@code image/x-portable-bitmap}. Some file formats have * official MIME types but may sometimes be referred to using * their previous unofficial designations, such as * {@code image/x-png} instead of the official * {@code image/png}. Finally, a single service provider may * be capable of parsing multiple distinct types from the MIME * point of view, for example {@code image/x-xbitmap} and * {@code image/x-xpixmap}. * *

Returning a particular MIME type does not guarantee that * files claiming to be of that type can be processed; it merely * indicates that it may be worthwhile attempting to decode or * encode such files using this service provider. * * @return an array of {@code String}s or length at least 1 * containing MIME types associated with this reader or writer, or * {@code null}. */ public String[] getMIMETypes() { return MIMETypes == null ? null : MIMETypes.clone(); } /** * Returns the fully-qualified class name of the * {@code ImageReader} or {@code ImageWriter} plug-in * associated with this service provider. * * @return the class name, as a non-{@code null} * {@code String}. */ public String getPluginClassName() { return pluginClassName; } /** * Returns {@code true} if the standard metadata format is * among the document formats recognized by the * {@code getAsTree} and {@code setFromTree} methods on * the stream metadata objects produced or consumed by this * plug-in. * * @return {@code true} if the standard format is supported * for stream metadata. */ public boolean isStandardStreamMetadataFormatSupported() { return supportsStandardStreamMetadataFormat; } /** * Returns the name of the "native" stream metadata format for * this plug-in, which typically allows for lossless encoding and * transmission of the stream metadata stored in the format handled by * this plug-in. If no such format is supported, * {@code null} will be returned. * *

The default implementation returns the * {@code nativeStreamMetadataFormatName} instance variable, * which is typically set by the constructor. * * @return the name of the native stream metadata format, or * {@code null}. * */ public String getNativeStreamMetadataFormatName() { return nativeStreamMetadataFormatName; } /** * Returns an array of {@code String}s containing the names * of additional document formats, other than the native and * standard formats, recognized by the * {@code getAsTree} and {@code setFromTree} methods on * the stream metadata objects produced or consumed by this * plug-in. * *

If the plug-in does not handle metadata, null should be * returned. * *

The set of formats may differ according to the particular * images being read or written; this method should indicate all * the additional formats supported by the plug-in under any * circumstances. * *

The default implementation returns a clone of the * {@code extraStreamMetadataFormatNames} instance variable, * which is typically set by the constructor. * * @return an array of {@code String}s, or null. * * @see IIOMetadata#getMetadataFormatNames * @see #getExtraImageMetadataFormatNames * @see #getNativeStreamMetadataFormatName */ public String[] getExtraStreamMetadataFormatNames() { return extraStreamMetadataFormatNames == null ? null : extraStreamMetadataFormatNames.clone(); } /** * Returns {@code true} if the standard metadata format is * among the document formats recognized by the * {@code getAsTree} and {@code setFromTree} methods on * the image metadata objects produced or consumed by this * plug-in. * * @return {@code true} if the standard format is supported * for image metadata. */ public boolean isStandardImageMetadataFormatSupported() { return supportsStandardImageMetadataFormat; } /** * Returns the name of the "native" image metadata format for * this plug-in, which typically allows for lossless encoding and * transmission of the image metadata stored in the format handled by * this plug-in. If no such format is supported, * {@code null} will be returned. * *

The default implementation returns the * {@code nativeImageMetadataFormatName} instance variable, * which is typically set by the constructor. * * @return the name of the native image metadata format, or * {@code null}. * * @see #getExtraImageMetadataFormatNames */ public String getNativeImageMetadataFormatName() { return nativeImageMetadataFormatName; } /** * Returns an array of {@code String}s containing the names * of additional document formats, other than the native and * standard formats, recognized by the * {@code getAsTree} and {@code setFromTree} methods on * the image metadata objects produced or consumed by this * plug-in. * *

If the plug-in does not handle image metadata, null should * be returned. * *

The set of formats may differ according to the particular * images being read or written; this method should indicate all * the additional formats supported by the plug-in under any circumstances. * *

The default implementation returns a clone of the * {@code extraImageMetadataFormatNames} instance variable, * which is typically set by the constructor. * * @return an array of {@code String}s, or null. * * @see IIOMetadata#getMetadataFormatNames * @see #getExtraStreamMetadataFormatNames * @see #getNativeImageMetadataFormatName */ public String[] getExtraImageMetadataFormatNames() { return extraImageMetadataFormatNames == null ? null : extraImageMetadataFormatNames.clone(); } /** * Returns an {@code IIOMetadataFormat} object describing the * given stream metadata format, or {@code null} if no * description is available. The supplied name must be the native * stream metadata format name, the standard metadata format name, * or one of those returned by * {@code getExtraStreamMetadataFormatNames}. * * @param formatName the desired stream metadata format. * * @return an {@code IIOMetadataFormat} object. * * @exception IllegalArgumentException if {@code formatName} * is {@code null} or is not a supported name. */ public IIOMetadataFormat getStreamMetadataFormat(String formatName) { return getMetadataFormat(formatName, supportsStandardStreamMetadataFormat, nativeStreamMetadataFormatName, nativeStreamMetadataFormatClassName, extraStreamMetadataFormatNames, extraStreamMetadataFormatClassNames); } /** * Returns an {@code IIOMetadataFormat} object describing the * given image metadata format, or {@code null} if no * description is available. The supplied name must be the native * image metadata format name, the standard metadata format name, * or one of those returned by * {@code getExtraImageMetadataFormatNames}. * * @param formatName the desired image metadata format. * * @return an {@code IIOMetadataFormat} object. * * @exception IllegalArgumentException if {@code formatName} * is {@code null} or is not a supported name. */ public IIOMetadataFormat getImageMetadataFormat(String formatName) { return getMetadataFormat(formatName, supportsStandardImageMetadataFormat, nativeImageMetadataFormatName, nativeImageMetadataFormatClassName, extraImageMetadataFormatNames, extraImageMetadataFormatClassNames); } private IIOMetadataFormat getMetadataFormat(String formatName, boolean supportsStandard, String nativeName, String nativeClassName, String [] extraNames, String [] extraClassNames) { if (formatName == null) { throw new IllegalArgumentException("formatName == null!"); } if (supportsStandard && formatName.equals (IIOMetadataFormatImpl.standardMetadataFormatName)) { return IIOMetadataFormatImpl.getStandardFormatInstance(); } String formatClassName = null; if (formatName.equals(nativeName)) { formatClassName = nativeClassName; } else if (extraNames != null) { for (int i = 0; i < extraNames.length; i++) { if (formatName.equals(extraNames[i])) { formatClassName = extraClassNames[i]; break; // out of for } } } if (formatClassName == null) { throw new IllegalArgumentException("Unsupported format name"); } try { // Try to load from the same location as the module of the SPI final String className = formatClassName; PrivilegedAction> pa = () -> { return getMetadataFormatClass(className); }; Class cls = AccessController.doPrivileged(pa); Method meth = cls.getMethod("getInstance"); return (IIOMetadataFormat) meth.invoke(null); } catch (Exception e) { RuntimeException ex = new IllegalStateException ("Can't obtain format"); ex.initCause(e); throw ex; } } // If updating this method also see the same in IIOMetadata.java private Class getMetadataFormatClass(String formatClassName) { Module thisModule = ImageReaderWriterSpi.class.getModule(); Module targetModule = this.getClass().getModule(); Class c = null; try { ClassLoader cl = this.getClass().getClassLoader(); c = Class.forName(formatClassName, false, cl); if (!IIOMetadataFormat.class.isAssignableFrom(c)) { return null; } } catch (ClassNotFoundException e) { } if (thisModule.equals(targetModule) || c == null) { return c; } if (targetModule.isNamed()) { int i = formatClassName.lastIndexOf("."); String pn = i > 0 ? formatClassName.substring(0, i) : ""; if (!targetModule.isExported(pn, thisModule)) { throw new IllegalStateException("Class " + formatClassName + " in named module must be exported to java.desktop module."); } } return c; } }





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