imageio/spi/InputStreamImageInputStreamSpi.java

/*
 * Copyright (c) 2000, 2010, Oracle and/or its affiliates. All rights reserved.
 * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
 *
 * This code is free software; you can redistribute it and/or modify it
 * under the terms of the GNU General Public License version 2 only, as
 * published by the Free Software Foundation.  Oracle designates this
 * particular file as subject to the "Classpath" exception as provided
 * by Oracle 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 Oracle, 500 Oracle Parkway, Redwood Shores, CA 94065 USA
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package com.sun.imageio.spi;

import java.io.File;
import java.io.InputStream;
import java.io.IOException;
import java.util.Locale;
import javax.imageio.spi.ImageInputStreamSpi;
import javax.imageio.stream.ImageInputStream;
import javax.imageio.stream.FileCacheImageInputStream;
import javax.imageio.stream.MemoryCacheImageInputStream;

public class InputStreamImageInputStreamSpi extends ImageInputStreamSpi {

    private static final String vendorName = "Oracle Corporation";

    private static final String version = "1.0";

    private static final Class inputClass = InputStream.class;

    public InputStreamImageInputStreamSpi() {
        super(vendorName, version, inputClass);
    }

    public String getDescription(Locale locale) {
        return "Service provider that instantiates a FileCacheImageInputStream or MemoryCacheImageInputStream from an InputStream";
    }

    public boolean canUseCacheFile() {
        return true;
    }

    public boolean needsCacheFile() {
        return false;
    }

    public ImageInputStream createInputStreamInstance(Object input,
                                                      boolean useCache,
                                                      File cacheDir)
        throws IOException {
        if (input instanceof InputStream) {
            InputStream is = (InputStream)input;

            if (useCache) {
                return new FileCacheImageInputStream(is, cacheDir);
            } else {
                return new MemoryCacheImageInputStream(is);
            }
        } else {
            throw new IllegalArgumentException();
        }
    }
}