lol: Added exception when invalid argument is passed to method

Signed-off-by: Stefan Andritoiu <stefan.andritoiu@intel.com>
Signed-off-by: Mihai Tudor Panu <mihai.tudor.panu@intel.com>

examples/java/LoL_exampleSample.java

@@ -41,9 +41,7 @@ public class LoL_exampleSample {
 		int x = 0, y = 0;
 		while (true) {
 			// revert pixel
-			short pixel = sensor.getPixel(x, y);
-			pixel = (short) ((pixel == 0) ? 1 : 0);
-			sensor.setPixel(x, y, pixel);
+			sensor.setPixel(x, y, sensor.getPixel(x, y));
 
 			if (++x == 13) {
 				x = 0;

src/lol/lol.cxx

@@ -168,20 +168,22 @@ unsigned char* LoL::getFramebuffer() {
     return framebuffer;
 }
 
-unsigned char LoL::setPixel(int x, int y, unsigned char pixel)
+void LoL::setPixel(int x, int y, bool pixel)
 {
     if (x < 0 || y < 0 || x >= LOL_X || y >= LOL_Y)
-        return -1;
+        throw std::invalid_argument(std::string(__FUNCTION__) +
+                ": pixel coordinates out of bounds");
 
-    framebuffer[x + LOL_X*y] = (pixel == 0) ? 0 : 1;
-    return 0;
+    framebuffer[x + LOL_X*y] = (pixel) ? 1 : 0;
+    return;
 }
 
-unsigned char LoL::getPixel(int x, int y)
+bool LoL::getPixel(int x, int y)
 {
     if (x < 0 || y < 0 || x >= LOL_X || y >= LOL_Y)
-        return -1;
+        throw std::invalid_argument(std::string(__FUNCTION__) +
+                ": pixel coordinates out of bounds");
 
-    return (framebuffer[x + LOL_X*y] == 0) ? 0 : 1;
+    return (framebuffer[x + LOL_X*y] == 0) ? false : true;
 }
 

src/lol/lol.h

@@ -77,18 +77,19 @@ class LoL {
          * Gets a pixel at specified coordinates
          * @param x Coordinate x
          * @param y Coordinate y
-         * @return 1 if the pixel is on, 0 if off, -1 on error
+         * @return true if the pixel is on, false if off
+         * @throws std::invalid_argument if pixel is out of bounds
          */
-        unsigned char getPixel(int x, int y);
+        bool getPixel(int x, int y);
 
         /**
          * Sets a pixel at specified coordinates
          * @param x Coordinate x
          * @param y Coordinate y
-         * @param pixel 0 is off, 1 is on
-         * @return 0 if successful, -1 on error
+         * @param pixel false is off, true is on
+         * @throws std::invalid_argument if pixel is out of bounds
          */
-        unsigned char setPixel(int x, int y, unsigned char pixel);
+        void setPixel(int x, int y, bool pixel);
 
     private:
         mraa_gpio_context m_LoLCtx[14];