Fix exceptions for readers, add path writer.

src/main/org/insa/graph/io/BinaryWriter.java

@@ -0,0 +1,30 @@
+package org.insa.graph.io;
+
+import java.io.DataOutputStream;
+import java.io.IOException;
+
+public abstract class BinaryWriter {
+
+    // Output stream.
+    protected DataOutputStream dos;
+
+    /**
+     * @param dos
+     */
+    protected BinaryWriter(DataOutputStream dos) {
+        this.dos = dos;
+    }
+
+    /**
+     * Write a 24-bits integer in BigEndian to the output stream.
+     * 
+     * @param value
+     * 
+     * @throws IOException
+     */
+    protected void write24bits(int value) throws IOException {
+        dos.writeShort(value >> 8);
+        dos.writeByte(value & 0xff);
+    }
+
+}