package org.apache.poi.poifs.nio;
+import java.io.File;
+import java.io.FileNotFoundException;
import java.io.IOException;
+import java.io.RandomAccessFile;
import java.nio.ByteBuffer;
import java.nio.channels.FileChannel;
+import org.apache.poi.util.IOUtils;
+
/**
* A POIFS {@link DataSource} backed by a File
*/
public class FileBackedDataSource extends DataSource {
- private FileChannel file;
- public FileBackedDataSource(FileChannel file) {
- this.file = file;
+ private FileChannel channel;
+
+ public FileBackedDataSource(File file) throws FileNotFoundException {
+ if(!file.exists()) {
+ throw new FileNotFoundException(file.toString());
+ }
+ this.channel = (new RandomAccessFile(file, "r")).getChannel();
+ }
+ public FileBackedDataSource(FileChannel channel) {
+ this.channel = channel;
}
public void read(ByteBuffer dst, long position) throws IOException {
- file.read(dst, position);
+ if(position >= size()) {
+ throw new IllegalArgumentException("Position " + position + " past the end of the file");
+ }
+
+ channel.position(position);
+ int worked = IOUtils.readFully(channel, dst);
+
+ if(worked == -1) {
+ throw new IllegalArgumentException("Position " + position + " past the end of the file");
+ }
}
public void write(ByteBuffer src, long position) throws IOException {
- file.write(src, position);
+ channel.write(src, position);
}
public long size() throws IOException {
- return file.size();
+ return channel.size();
}
public void close() throws IOException {
- file.close();
+ channel.close();
}
}
package org.apache.poi.poifs.nio;
-import java.io.IOException;
+import java.io.File;
+import java.nio.ByteBuffer;
+
+import org.apache.poi.POIDataSamples;
import junit.framework.TestCase;
*/
public class TestDataSource extends TestCase
{
- public void testFile() throws IOException {
- // TODO
+ private static POIDataSamples data = POIDataSamples.getPOIFSInstance();
+
+ public void testFile() throws Exception {
+ File f = data.getFile("Notes.ole2");
+
+ FileBackedDataSource ds = new FileBackedDataSource(f);
+ assertEquals(8192, ds.size());
+
+ // Start of file
+ ByteBuffer bs = ByteBuffer.allocate(4);
+ ds.read(bs, 0);
+ assertEquals(4, bs.capacity());
+ assertEquals(4, bs.position());
+ assertEquals(0xd0-256, bs.get(0));
+ assertEquals(0xcf-256, bs.get(1));
+ assertEquals(0x11-000, bs.get(2));
+ assertEquals(0xe0-256, bs.get(3));
+
+ // Mid way through
+ bs = ByteBuffer.allocate(8);
+ ds.read(bs, 0x400);
+ assertEquals(8, bs.capacity());
+ assertEquals(8, bs.position());
+ assertEquals((byte)'R', bs.get(0));
+ assertEquals(0, bs.get(1));
+ assertEquals((byte)'o', bs.get(2));
+ assertEquals(0, bs.get(3));
+ assertEquals((byte)'o', bs.get(4));
+ assertEquals(0, bs.get(5));
+ assertEquals((byte)'t', bs.get(6));
+ assertEquals(0, bs.get(7));
+
+ // Can go to the end, but not past it
+ bs.clear();
+ ds.read(bs, 8190);
+ assertEquals(2, bs.position());
+
+ // Can't go off the end
+ try {
+ bs.clear();
+ ds.read(bs, 8192);
+ fail("Shouldn't be able to read off the end of the file");
+ } catch(IllegalArgumentException e) {}
}
- public void testByteArray() throws IOException {
- // TODO
+ public void testByteArray() throws Exception {
+ byte[] data = new byte[256];
+ byte b;
+ for(int i=0; i<data.length; i++) {
+ b = (byte)i;
+ data[i] = b;
+ }
+
+ ByteArrayBackedDataSource ds = new ByteArrayBackedDataSource(data);
+
+ // Start
+ ByteBuffer bs = ByteBuffer.allocate(4);
+ ds.read(bs, 0);
+ assertEquals(4, bs.capacity());
+ assertEquals(4, bs.position());
+ assertEquals(0x00, bs.get(0));
+ assertEquals(0x01, bs.get(1));
+ assertEquals(0x02, bs.get(2));
+ assertEquals(0x03, bs.get(3));
+
+ // Middle
+ bs.clear();
+ ds.read(bs, 100);
+ assertEquals(4, bs.capacity());
+ assertEquals(4, bs.position());
+ assertEquals(100, bs.get(0));
+ assertEquals(101, bs.get(1));
+ assertEquals(102, bs.get(2));
+ assertEquals(103, bs.get(3));
+
+ // End
+ bs.clear();
+ ds.read(bs, 252);
+ assertEquals(4, bs.capacity());
+ assertEquals(4, bs.position());
+ assertEquals(-4, bs.get(0));
+ assertEquals(-3, bs.get(1));
+ assertEquals(-2, bs.get(2));
+ assertEquals(-1, bs.get(3));
+
+ // Off the end
+ bs.clear();
+ ds.read(bs, 254);
+ assertEquals(4, bs.capacity());
+ assertEquals(2, bs.position());
+ assertEquals(-2, bs.get(0));
+ assertEquals(-1, bs.get(1));
+
+ // Past the end
+ bs.clear();
+ try {
+ ds.read(bs, 256);
+ fail("Shouldn't be able to read off the end");
+ } catch(IndexOutOfBoundsException e) {}
+
+
+ // Overwrite
+ bs.clear();
+ bs.put(0, (byte)-55);
+ bs.put(1, (byte)-54);
+ bs.put(2, (byte)-53);
+ bs.put(3, (byte)-52);
+
+ ds.write(bs, 40);
+ bs.clear();
+ ds.read(bs, 40);
+
+ assertEquals(4, bs.position());
+ assertEquals(-55, bs.get(0));
+ assertEquals(-54, bs.get(1));
+ assertEquals(-53, bs.get(2));
+ assertEquals(-52, bs.get(3));
+
+ // Append
+ bs.clear();
+ bs.put(0, (byte)-55);
+ bs.put(1, (byte)-54);
+ bs.put(2, (byte)-53);
+ bs.put(3, (byte)-52);
+
+ assertEquals(256, ds.size());
+ ds.write(bs, 256);
+ assertEquals(260, ds.size());
+
+ bs.clear();
+ ds.read(bs, 256);
+ assertEquals(4, bs.position());
+ assertEquals(-55, bs.get(0));
+ assertEquals(-54, bs.get(1));
+ assertEquals(-53, bs.get(2));
+ assertEquals(-52, bs.get(3));
}
}