fix: isClosedRequested now sets flag to false after call

added support for isFocused

src/java/org/lwjgl/Window.java

@@ -37,6 +37,9 @@ public abstract class Window {
 
 	/** Whether the window is currently minimized */
 	private boolean minimized;
+  
+  /** Whether the window has focus */
+  private boolean focused = true;
 	
 	/** Whether the window has been asked to close by the user or underlying OS */
 	private boolean closeRequested;
@@ -131,13 +134,16 @@ public abstract class Window {
 	 */
 	private native void nSetTitle(String title);
 
-	/**
-	 * @return true if the user or operating system has asked the window to close
-	 */
-	public final boolean isCloseRequested() {
-		assert isCreated();
-		return closeRequested;
-	}
+  /**
+   * @return true if the user or operating system has asked the window to close
+   */
+  public final boolean isCloseRequested() {
+    assert isCreated();
+    
+    boolean currentValue = closeRequested;
+    closeRequested = false;
+    return currentValue;
+  }
 	
 	/**
 	 * @return true if the window is minimized or otherwise not visible
@@ -146,6 +152,14 @@ public abstract class Window {
 		assert isCreated();
 		return minimized;
 	}
+  
+  /**
+   * @return true if window is focused
+   */
+  public final boolean isFocused() {
+    assert isCreated();
+    return focused;
+  }
 	
 	/**
 	 * Minimize the game and allow the operating system's default display to become