panda.lang.builder.Builder Maven / Gradle / Ivy

Go to download

Show more of this group Show more artifacts with this name
Show all versions of panda-core Show documentation

Panda Core is the core module of Panda Framework, it contains commonly used utility classes similar to apache-commons.

There is a newer version: 1.8.0

package panda.lang.builder;

/**
 * 
 * The Builder interface is designed to designate a class as a builder 
 * object in the Builder design pattern. Builders are capable of creating and 
 * configuring objects or results that normally take multiple steps to construct 
 * or are very complex to derive. 
 * 
 * 
 * 
 * The builder interface defines a single method, {@link #build()}, that 
 * classes must implement. The result of this method should be the final 
 * configured object or result after all building operations are performed.
 * 
 * 
 * 
 * It is a recommended practice that the methods supplied to configure the 
 * object or result being built return a reference to {@code this} so that
 * method calls can be chained together.
 * 
 * 
 * 
 * Example Builder:
 * 
 * class FontBuilder implements Builder<Font> {
 *     private Font font;
 *     
 *     public FontBuilder(String fontName) {
 *         this.font = new Font(fontName, Font.PLAIN, 12);
 *     }
 * 
 *     public FontBuilder bold() {
 *         this.font = this.font.deriveFont(Font.BOLD);
 *         return this; // Reference returned so calls can be chained
 *     }
 *     
 *     public FontBuilder size(float pointSize) {
 *         this.font = this.font.deriveFont(pointSize);
 *         return this; // Reference returned so calls can be chained
 *     }
 * 
 *     // Other Font construction methods
 * 
 *     public Font build() {
 *         return this.font;
 *     }
 * }
 * 
 * 
 * Example Builder Usage:
 *  * Font bold14ptSansSerifFont = new FontBuilder(Font.SANS_SERIF).bold()
 *                                                              .size(14.0f)
 *                                                              .build();
 * 
 * 
 * 
 * @param  the type of object that the builder will construct or compute.
 * 
 */
public interface Builder {

	/**
	 * Returns a reference to the object being constructed or result being calculated by the
	 * builder.
	 * 
	 * @return the object constructed or result calculated by the builder.
	 */
	T build();
}