Added a number of container classes that will be used for
Flow Path computation and installation.
diff --git a/src/main/java/net/floodlightcontroller/util/FlowEntryErrorState.java b/src/main/java/net/floodlightcontroller/util/FlowEntryErrorState.java
new file mode 100644
index 0000000..63c103d
--- /dev/null
+++ b/src/main/java/net/floodlightcontroller/util/FlowEntryErrorState.java
@@ -0,0 +1,65 @@
+package net.floodlightcontroller.util;
+
+/**
+ * The class representing the Flow Entry error state.
+ */
+public class FlowEntryErrorState {
+    private short type;	// The error type (e.g., see OF-1.3.1 spec, pp. 95)
+    private short code;	// The error code (e.g., see OF-1.3.1 spec, pp. 95)
+
+    /**
+     * Default constructor.
+     */
+    public FlowEntryErrorState() {
+	this.type = 0;
+	this.code = 0;
+    }
+
+    /**
+     * Constructor for a given error type and code.
+     *
+     * @param type the error type to use.
+     * @param code the error code to use.
+     */
+    public FlowEntryErrorState(short type, short code) {
+	this.type = type;
+	this.code = code;
+    }
+
+    /**
+     * Get the error type.
+     *
+     * @return the error type.
+     */
+    public short type() { return type; }
+
+    /**
+     * Get the error code.
+     *
+     * @return the error code.
+     */
+    public short code() { return code; }
+
+    /**
+     * Set the values of the error type and code.
+     *
+     * @param type the error type to use.
+     * @param code the error code to use.
+     */
+    public void setValue(short type, short code) {
+	this.type = type;
+	this.code = code;
+    }
+
+    /**
+     * Convert the error type and code to a string.
+     *
+     * @return the error type and code as a string.
+     */
+    @Override
+    public String toString() {
+	String ret = "";
+	// TODO: Implement it!
+	return ret;
+    }
+}