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src/java.desktop/share/classes/java/awt/Canvas.java

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*** 27,43 **** import java.awt.image.BufferStrategy; import java.awt.peer.CanvasPeer; import javax.accessibility.*; /** ! * A <code>Canvas</code> component represents a blank rectangular * area of the screen onto which the application can draw or from * which the application can trap input events from the user. * <p> ! * An application must subclass the <code>Canvas</code> class in * order to get useful functionality such as creating a custom ! * component. The <code>paint</code> method must be overridden * in order to perform custom graphics on the canvas. * * @author Sami Shaio * @since 1.0 */ --- 27,43 ---- import java.awt.image.BufferStrategy; import java.awt.peer.CanvasPeer; import javax.accessibility.*; /** ! * A {@code Canvas} component represents a blank rectangular * area of the screen onto which the application can draw or from * which the application can trap input events from the user. * <p> ! * An application must subclass the {@code Canvas} class in * order to get useful functionality such as creating a custom ! * component. The {@code paint} method must be overridden * in order to perform custom graphics on the canvas. * * @author Sami Shaio * @since 1.0 */
*** 106,116 **** } /** * Paints this canvas. * <p> ! * Most applications that subclass <code>Canvas</code> should * override this method in order to perform some useful operation * (typically, custom painting of the canvas). * The default operation is simply to clear the canvas. * Applications that override this method need not call * super.paint(g). --- 106,116 ---- } /** * Paints this canvas. * <p> ! * Most applications that subclass {@code Canvas} should * override this method in order to perform some useful operation * (typically, custom painting of the canvas). * The default operation is simply to clear the canvas. * Applications that override this method need not call * super.paint(g).
*** 124,137 **** } /** * Updates this canvas. * <p> ! * This method is called in response to a call to <code>repaint</code>. * The canvas is first cleared by filling it with the background * color, and then completely redrawn by calling this canvas's ! * <code>paint</code> method. * Note: applications that override this method should either call * super.update(g) or incorporate the functionality described * above into their own code. * * @param g the specified Graphics context --- 124,137 ---- } /** * Updates this canvas. * <p> ! * This method is called in response to a call to {@code repaint}. * The canvas is first cleared by filling it with the background * color, and then completely redrawn by calling this canvas's ! * {@code paint} method. * Note: applications that override this method should either call * super.update(g) or incorporate the functionality described * above into their own code. * * @param g the specified Graphics context
*** 149,159 **** /** * Creates a new strategy for multi-buffering on this component. * Multi-buffering is useful for rendering performance. This method * attempts to create the best strategy available with the number of ! * buffers supplied. It will always create a <code>BufferStrategy</code> * with that number of buffers. * A page-flipping strategy is attempted first, then a blitting strategy * using accelerated buffers. Finally, an unaccelerated blitting * strategy is used. * <p> --- 149,159 ---- /** * Creates a new strategy for multi-buffering on this component. * Multi-buffering is useful for rendering performance. This method * attempts to create the best strategy available with the number of ! * buffers supplied. It will always create a {@code BufferStrategy} * with that number of buffers. * A page-flipping strategy is attempted first, then a blitting strategy * using accelerated buffers. Finally, an unaccelerated blitting * strategy is used. * <p>
*** 178,205 **** * <p> * Each time this method * is called, the existing buffer strategy for this component is discarded. * @param numBuffers number of buffers to create * @param caps the required capabilities for creating the buffer strategy; ! * cannot be <code>null</code> * @exception AWTException if the capabilities supplied could not be * supported or met; this may happen, for example, if there is not enough * accelerated memory currently available, or if page flipping is specified * but not possible. * @exception IllegalArgumentException if numBuffers is less than 1, or if ! * caps is <code>null</code> * @see #getBufferStrategy * @since 1.4 */ public void createBufferStrategy(int numBuffers, BufferCapabilities caps) throws AWTException { super.createBufferStrategy(numBuffers, caps); } /** ! * Returns the <code>BufferStrategy</code> used by this component. This ! * method will return null if a <code>BufferStrategy</code> has not yet * been created or has been disposed. * * @return the buffer strategy used by this component * @see #createBufferStrategy * @since 1.4 --- 178,205 ---- * <p> * Each time this method * is called, the existing buffer strategy for this component is discarded. * @param numBuffers number of buffers to create * @param caps the required capabilities for creating the buffer strategy; ! * cannot be {@code null} * @exception AWTException if the capabilities supplied could not be * supported or met; this may happen, for example, if there is not enough * accelerated memory currently available, or if page flipping is specified * but not possible. * @exception IllegalArgumentException if numBuffers is less than 1, or if ! * caps is {@code null} * @see #getBufferStrategy * @since 1.4 */ public void createBufferStrategy(int numBuffers, BufferCapabilities caps) throws AWTException { super.createBufferStrategy(numBuffers, caps); } /** ! * Returns the {@code BufferStrategy} used by this component. This ! * method will return null if a {@code BufferStrategy} has not yet * been created or has been disposed. * * @return the buffer strategy used by this component * @see #createBufferStrategy * @since 1.4
*** 230,240 **** return accessibleContext; } /** * This class implements accessibility support for the ! * <code>Canvas</code> class. It provides an implementation of the * Java Accessibility API appropriate to canvas user-interface elements. * @since 1.3 */ protected class AccessibleAWTCanvas extends AccessibleAWTComponent { --- 230,240 ---- return accessibleContext; } /** * This class implements accessibility support for the ! * {@code Canvas} class. It provides an implementation of the * Java Accessibility API appropriate to canvas user-interface elements. * @since 1.3 */ protected class AccessibleAWTCanvas extends AccessibleAWTComponent {
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