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src/java.desktop/share/classes/javax/swing/Painter.java

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*** 26,52 **** import java.awt.Graphics2D; /** * <p>A painting delegate. The Painter interface defines exactly one method, ! * <code>paint</code>. It is used in situations where the developer can change * the painting routine of a component without having to resort to subclassing * the component. It is also generically useful when doing any form of painting * delegation.</p> * ! * <p><code>Painter</code>s are simply encapsulations of Java2D code and make ! * it fairly trivial to reuse existing <code>Painter</code>s or to combine * them together. Implementations of this interface are also trivial to write, ! * such that if you can't find a <code>Painter</code> that does what you need, ! * you can write one with minimal effort. Writing a <code>Painter</code> requires * knowledge of Java2D.</p> * ! * <p>A <code>Painter</code> may be created with a type parameter. This type will be ! * expected in the <code>paint</code> method. For example, you may wish to write a ! * <code>Painter</code> that only works with subclasses of {@link java.awt.Component}. ! * In that case, when the <code>Painter</code> is declared, you may declare that ! * it requires a <code>Component</code>, allowing the paint method to be type safe. Ex: * <pre> * {@code * Painter<Component> p = new Painter<Component>() { * public void paint(Graphics2D g, Component c, int width, int height) { * g.setColor(c.getBackground()); --- 26,52 ---- import java.awt.Graphics2D; /** * <p>A painting delegate. The Painter interface defines exactly one method, ! * {@code paint}. It is used in situations where the developer can change * the painting routine of a component without having to resort to subclassing * the component. It is also generically useful when doing any form of painting * delegation.</p> * ! * <p>{@code Painter}s are simply encapsulations of Java2D code and make ! * it fairly trivial to reuse existing {@code Painter}s or to combine * them together. Implementations of this interface are also trivial to write, ! * such that if you can't find a {@code Painter} that does what you need, ! * you can write one with minimal effort. Writing a {@code Painter} requires * knowledge of Java2D.</p> * ! * <p>A {@code Painter} may be created with a type parameter. This type will be ! * expected in the {@code paint} method. For example, you may wish to write a ! * {@code Painter} that only works with subclasses of {@link java.awt.Component}. ! * In that case, when the {@code Painter} is declared, you may declare that ! * it requires a {@code Component}, allowing the paint method to be type safe. Ex: * <pre> * {@code * Painter<Component> p = new Painter<Component>() { * public void paint(Graphics2D g, Component c, int width, int height) { * g.setColor(c.getBackground());
*** 62,103 **** * @since 1.7 */ public interface Painter<T> { /** * <p>Renders to the given {@link java.awt.Graphics2D} object. Implementations ! * of this method <em>may</em> modify state on the <code>Graphics2D</code>, and are not * required to restore that state upon completion. In most cases, it is recommended ! * that the caller pass in a scratch graphics object. The <code>Graphics2D</code> * must never be null.</p> * ! * <p>State on the graphics object may be honored by the <code>paint</code> method, * but may not be. For instance, setting the antialiasing rendering hint on the ! * graphics may or may not be respected by the <code>Painter</code> implementation.</p> * * <p>The supplied object parameter acts as an optional configuration argument. ! * For example, it could be of type <code>Component</code>. A <code>Painter</code> ! * that expected it could then read state from that <code>Component</code> and * use the state for painting. For example, an implementation may read the * backgroundColor and use that.</p> * ! * <p>Generally, to enhance reusability, most standard <code>Painter</code>s ignore ! * this parameter. They can thus be reused in any context. The <code>object</code> * may be null. Implementations must not throw a NullPointerException if the object * parameter is null.</p> * ! * <p>Finally, the <code>width</code> and <code>height</code> arguments specify the ! * width and height that the <code>Painter</code> should paint into. More * specifically, the specified width and height instruct the painter that it should * paint fully within this width and height. Any specified clip on the ! * <code>g</code> param will further constrain the region.</p> * ! * <p>For example, suppose I have a <code>Painter</code> implementation that draws * a gradient. The gradient goes from white to black. It "stretches" to fill the ! * painted region. Thus, if I use this <code>Painter</code> to paint a 500 x 500 * region, the far left would be black, the far right would be white, and a smooth * gradient would be painted between. I could then, without modification, reuse the ! * <code>Painter</code> to paint a region that is 20x20 in size. This region would * also be black on the left, white on the right, and a smooth gradient painted * between.</p> * * @param g The Graphics2D to render to. This must not be null. * @param object an optional configuration parameter. This may be null. --- 62,103 ---- * @since 1.7 */ public interface Painter<T> { /** * <p>Renders to the given {@link java.awt.Graphics2D} object. Implementations ! * of this method <em>may</em> modify state on the {@code Graphics2D}, and are not * required to restore that state upon completion. In most cases, it is recommended ! * that the caller pass in a scratch graphics object. The {@code Graphics2D} * must never be null.</p> * ! * <p>State on the graphics object may be honored by the {@code paint} method, * but may not be. For instance, setting the antialiasing rendering hint on the ! * graphics may or may not be respected by the {@code Painter} implementation.</p> * * <p>The supplied object parameter acts as an optional configuration argument. ! * For example, it could be of type {@code Component}. A {@code Painter} ! * that expected it could then read state from that {@code Component} and * use the state for painting. For example, an implementation may read the * backgroundColor and use that.</p> * ! * <p>Generally, to enhance reusability, most standard {@code Painter}s ignore ! * this parameter. They can thus be reused in any context. The {@code object} * may be null. Implementations must not throw a NullPointerException if the object * parameter is null.</p> * ! * <p>Finally, the {@code width} and {@code height} arguments specify the ! * width and height that the {@code Painter} should paint into. More * specifically, the specified width and height instruct the painter that it should * paint fully within this width and height. Any specified clip on the ! * {@code g} param will further constrain the region.</p> * ! * <p>For example, suppose I have a {@code Painter} implementation that draws * a gradient. The gradient goes from white to black. It "stretches" to fill the ! * painted region. Thus, if I use this {@code Painter} to paint a 500 x 500 * region, the far left would be black, the far right would be white, and a smooth * gradient would be painted between. I could then, without modification, reuse the ! * {@code Painter} to paint a region that is 20x20 in size. This region would * also be black on the left, white on the right, and a smooth gradient painted * between.</p> * * @param g The Graphics2D to render to. This must not be null. * @param object an optional configuration parameter. This may be null.
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