Begin work on DataFile

src/test/java/net/runelite/cache/fs/DataFileTest.java

@@ -0,0 +1,36 @@
+package net.runelite.cache.fs;
+
+import java.io.File;
+import java.io.IOException;
+import java.nio.ByteBuffer;
+import org.junit.Assert;
+import org.junit.Test;
+
+public class DataFileTest
+{
+	@Test
+	public void test1() throws IOException
+	{
+		File file = new File("d:/rs/07/test/test.dat");
+		DataFile df = new DataFile(42, file);
+		int sector = df.write(3, ByteBuffer.wrap("test".getBytes()));
+		ByteBuffer buf = df.read(3, sector, 4);
+		String str = new String(buf.array());
+		Assert.assertEquals("test", str);
+		file.delete();
+	}
+	
+	@Test
+	public void test2() throws IOException
+	{
+		byte[] b = new byte[1024];
+		for (int i = 0; i < 1024; ++i) b[i] = (byte) i;
+		
+		File file = new File("d:/rs/07/test/test.dat");
+		DataFile df = new DataFile(42, file);
+		int sector = df.write(0x1FFFF, ByteBuffer.wrap(b));
+		ByteBuffer buf = df.read(0x1FFFF, sector, b.length);
+		Assert.assertArrayEquals(b, buf.array());
+		file.delete();
+	}
+}