1 files changed, 119 insertions, 0 deletions
diff --git a/WPIJavaCV/src/edu/wpi/first/wpijavacv/WPIDisposable.java b/WPIJavaCV/src/edu/wpi/first/wpijavacv/WPIDisposable.java
new file mode 100644
index 0000000..6d4b23b
--- /dev/null
+++ b/WPIJavaCV/src/edu/wpi/first/wpijavacv/WPIDisposable.java
@@ -0,0 +1,119 @@
+package edu.wpi.first.wpijavacv;
+
+import com.googlecode.javacpp.Pointer;
+
+/**
+ * This class is an abstract class defining disposable elements.
+ * It is the superclass of most things which links directly to the javacv core.
+ * 
+ * @author Joe Grinstead
+ */
+public abstract class WPIDisposable {
+
+    /** The memory pool to report to when disposed, or null if there is none */
+    private WPIMemoryPool pool = null;
+    
+    /** Whether or not this is disposed */
+    private boolean disposed = false;
+
+    /**
+     * Sets the {@link WPIMemoryPool} that this disposable is linked to.
+     * @param pool the pool to link to (null is allowed)
+     */
+    protected void setPool(WPIMemoryPool pool) {
+        this.pool = pool;
+    }
+
+    protected WPIMemoryPool getPool() {
+        return pool;
+    }
+
+    /**
+     * Disposes this object.  This may be called multiple times.
+     *
+     * Programmers should call this when they no longer need an object.  However, even if they don't, this will be called
+     * when this object is collected by the garbage collector.
+     */
+    public void dispose() {
+        if (!disposed) {
+            disposed = true;
+            disposed();
+            if (pool != null) {
+                pool.removeFromPool(this);
+            }
+        }
+    }
+
+    /**
+     * This is called when {@link WPIDisposable#dispose() dispose()} is called for the first time.
+     * Subclasses should clear out whatever internal resources they are using.
+     */
+    protected abstract void disposed();
+
+    /**
+     * Returns whether or not this object is disposed.
+     * @return whether or not this object is disposed
+     *
+     * @see WPIDisposable#dispose() dispose()
+     */
+    public boolean isDisposed() {
+        return disposed;
+    }
+
+    /**
+     * Checks if this {@link WPIDisposable} has already been disposed.  If it has,
+     * then it will throw a {@link DisposedException} with a default message.
+     */
+    protected void validateDisposed() {
+        if (disposed) {
+            throw new DisposedException(this + " has been disposed");
+        }
+    }
+
+    /**
+     * Checks if this {@link WPIDisposable} has already been disposed.  If it has,
+     * then it will throw a {@link DisposedException} with the given message.
+     * @param message the message to give the exception
+     */
+    protected void validateDisposed(String message) {
+        if (disposed) {
+            throw new DisposedException(message);
+        }
+    }
+
+    /**
+     * Returns whether or not the given pointer is null in either the java sense or the javacv sense.
+     * @param pointer the pointer
+     * @return whether it is null
+     */
+    protected static boolean isNull(Pointer pointer) {
+        return pointer == null || pointer.isNull();
+    }
+
+    /**
+     * Attempts to free (in the c sense) the given pointer.  Does nothing if given null.
+     * @param pointer the pointer to free
+     */
+    protected static void free(Pointer pointer) {
+        if (pointer != null && !pointer.isNull()) {
+            pointer.deallocate();
+        }
+    }
+
+    /**
+     * An exception to be thrown if an element has already been disposed and the user attempts to
+     * perform an operation on it.
+     */
+    public static class DisposedException extends RuntimeException {
+
+        public DisposedException(String message) {
+            super(message);
+        }
+    }
+
+    @Override
+    protected void finalize() throws Throwable {
+        dispose();
+        super.finalize();
+    }
+}