ImageIOExtTest.java

package org.geotools.image.io;

import static org.junit.Assert.*;

import java.awt.image.RenderedImage;
import java.io.ByteArrayOutputStream;
import java.io.IOException;
import java.io.OutputStream;

import javax.imageio.ImageIO;
import javax.imageio.stream.FileCacheImageOutputStream;
import javax.imageio.stream.ImageOutputStream;
import javax.imageio.stream.MemoryCacheImageOutputStream;
import javax.media.jai.operator.ConstantDescriptor;

import org.geotools.image.io.ImageIOExt;
import org.junit.After;
import org.junit.Before;
import org.junit.Test;

public class ImageIOExtTest {

    private boolean useCache;

    @Before
    public void before() {
        useCache = ImageIO.getUseCache();
    }

    @After
    public void after() {
        ImageIO.setUseCache(useCache);
    }

    @Test
    public void testDefaultMemoryOutputStreams() throws Exception {
        ImageIO.setUseCache(false);
        testSameStreamClass();
    }
    
    @Test
    public void testDefaultFileOutputStreams() throws Exception {
        ImageIO.setUseCache(true);
        testSameStreamClass();
    }
    
    @Test 
    public void testThreshold() throws Exception {
        OutputStream os = new ByteArrayOutputStream();
        ImageIOExt.setFilesystemThreshold(100 * 100 * 3l);
        
        RenderedImage imageSmall = getTestRenderedImage(50, 50, 3);
        final ImageOutputStream iosSmall = ImageIOExt.createImageOutputStream(imageSmall, os);
        try {
            assertEquals(MemoryCacheImageOutputStream.class, iosSmall.getClass());
        } finally {
            iosSmall.close();
        }
        
        RenderedImage imageLarge = getTestRenderedImage(101, 101, 3);
        final ImageOutputStream iosLarge = ImageIOExt.createImageOutputStream(imageLarge, os);
        try {
            assertEquals(FileCacheImageOutputStream.class, iosLarge.getClass());
        } finally {
            iosLarge.close();
        }
    }

    void testSameStreamClass() throws IOException {
        OutputStream os = new ByteArrayOutputStream();
        RenderedImage image = getTestRenderedImage(50, 50, 1);

        ImageOutputStream iosExt = ImageIOExt.createImageOutputStream(image, os);
        ImageOutputStream iosStd = ImageIO.createImageOutputStream(os);

        assertEquals(iosExt.getClass(), iosStd.getClass());
    }

    RenderedImage getTestRenderedImage(int width, int height, int bands) {
        Byte[] values = new Byte[bands];
        for (int i = 0; i < values.length; i++) {
            values[i] = new Byte((byte) 0);
        }
        return ConstantDescriptor.create((float) width, (float) height, values, null);
    }
}