1 files changed, 92 insertions, 0 deletions
diff --git a/src/uk/org/ury/show/ShowChannel.java b/src/uk/org/ury/show/ShowChannel.java
new file mode 100644
index 0000000..6aa3ee8
--- /dev/null
+++ b/src/uk/org/ury/show/ShowChannel.java
@@ -0,0 +1,92 @@
+package uk.org.ury.show;
+
+import java.util.ArrayList;
+import java.util.List;
+
+
+/**
+ * A channel of ShowItems in a show.
+ * 
+ * @author  Matt Windsor
+ */
+
+public class ShowChannel
+{
+  /* Items enqueued in channel. */
+  private List<ShowItem> items;
+  
+  
+  /**
+   * Construct a new, empty channel.
+   */
+  
+  public
+  ShowChannel ()
+  {
+    items = new ArrayList<ShowItem> ();
+  }
+  
+  
+  /**
+   * Add a new item to the channel.
+   * 
+   * @param index  The position at which to add the item.
+   *               
+   * @param item   The new item to add.
+   * 
+   * @throws       IllegalArgumentException if the item is 
+   *               null, the index is negative or the index 
+   *               is out of bounds.
+   */
+  
+  public void
+  add (int index, ShowItem item)
+  {
+    if (item == null)
+      throw new IllegalArgumentException ("Item is null.");
+    
+    if (index < 0 || index >= items.size ())
+      throw new IllegalArgumentException ("Index " + index + 
+                                          " out of bounds.");
+    
+    items.add (index, item);
+  }
+  
+  
+  /**
+   * Add a new item to the end of the channel.
+   * 
+   * @param item  The new item to add.
+   */
+  
+  public void
+  add (ShowItem item)
+  {
+    if (item == null)
+      throw new IllegalArgumentException ("Item is null.");
+    
+    items.add (item);
+  }
+  
+  
+  /**
+   * Retrieve an item from the channel.
+   * 
+   * @param index  The index of the item to retrieve from the channel.
+   * 
+   * @return       the item at the given index in the list.
+   * 
+   * @throws       IllegalArgumentException if the index is negative
+   *               or overflowing.
+   */
+  
+  public ShowItem
+  get (int index)
+  {
+    if (index < 0 || index >= items.size ())
+      throw new IllegalArgumentException ("Index " + index + 
+                                          " out of bounds.");
+    
+    return items.get (index);
+  }
+}