}
}
+ /**
+ * Calculate checksum on input data
+ */
public static long calculateChecksum(byte[] data) {
Checksum sum = new CRC32();
sum.update(data, 0, data.length);
return sum.getValue();
}
+ /**
+ * Calculate checksum on all the data read from input stream.
+ *
+ * This should be more efficient than the equivalent code
+ * {@code IOUtils.calculateChecksum(IOUtils.toByteArray(stream))}
+ */
+ public static long calculateChecksum(InputStream stream) throws IOException {
+ Checksum sum = new CRC32();
+
+ byte[] buf = new byte[4096];
+ int count;
+ while ((count = stream.read(buf)) != -1) {
+ if (count > 0) {
+ sum.update(buf, 0, count);
+ }
+ }
+ return sum.getValue();
+ }
+
+
/**
* Quietly (no exceptions) close Closable resource. In case of error it will
* be printed to {@link IOUtils} class logger.
package org.apache.poi.xslf.usermodel;
import java.io.IOException;
+import java.io.InputStream;
import java.io.OutputStream;
import org.apache.poi.POIXMLDocumentPart;
super(part, rel);
}
+ /**
+ * An InputStream to read the picture data directly
+ * from the underlying package part
+ *
+ * @return InputStream
+ */
+ public InputStream getInputStream() throws IOException {
+ return getPackagePart().getInputStream();
+ }
+
/**
* Gets the picture data as a byte array.
- * <p>
- * Note, that this call might be expensive since all the picture data is copied into a temporary byte array.
- * You can grab the picture data directly from the underlying package part as follows:
- * <br/>
- * <code>
- * InputStream is = getPackagePart().getInputStream();
- * </code>
- * </p>
*
+ * You can grab the picture data directly from the underlying package part with the {@link #getInputStream()} method
+ *
* @return the Picture data.
*/
public byte[] getData() {
try {
- return IOUtils.toByteArray(getPackagePart().getInputStream());
+ return IOUtils.toByteArray(getInputStream());
} catch (IOException e) {
throw new POIXMLException(e);
}
long getChecksum(){
if(checksum == null){
- byte[] pictureData = getData();
- checksum = IOUtils.calculateChecksum(pictureData);
+ try {
+ checksum = IOUtils.calculateChecksum(getInputStream());
+ } catch (IOException e) {
+ throw new POIXMLException("Unable to calulate checksum", e);
+ }
}
return checksum;
}
OutputStream os = getPackagePart().getOutputStream();
os.write(data);
os.close();
+ // recalculate now since we already have the data bytes available anyhow
+ checksum = IOUtils.calculateChecksum(data);
}
import java.awt.Insets;\r
import java.awt.geom.Rectangle2D;\r
import java.awt.image.BufferedImage;\r
-import java.io.ByteArrayInputStream;\r
import java.net.URI;\r
\r
import javax.imageio.ImageIO;\r
* for other types sets the default size of 200x200 pixels.\r
*/\r
public void resize() {\r
- XSLFPictureData pict = getPictureData();\r
-\r
try {\r
- BufferedImage img = ImageIO.read(new ByteArrayInputStream(pict.getData()));\r
+ BufferedImage img = ImageIO.read(getPictureData().getInputStream());\r
setAnchor(new Rectangle2D.Double(0, 0, img.getWidth(), img.getHeight()));\r
}\r
catch (Exception e) {\r