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	/*
	* Licensed to the Apache Software Foundation (ASF) under one or more
	* contributor license agreements. See the NOTICE file distributed with
	* this work for additional information regarding copyright ownership.
	* The ASF licenses this file to You under the Apache License, Version 2.0
	* (the "License"); you may not use this file except in compliance with
	* the License. You may obtain a copy of the License at
	*
	* http://www.apache.org/licenses/LICENSE-2.0
	*
	* Unless required by applicable law or agreed to in writing, software
	* distributed under the License is distributed on an "AS IS" BASIS,
	* WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
	* See the License for the specific language governing permissions and
	* limitations under the License.
	*/
	package org.apache.commons.lang3.builder;

	/**
	* <p>
	* The Builder interface is designed to designate a class as a <em>builder</em>
	* 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.
	* </p>
	*
	* <p>
	* 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.
	* </p>
	*
	* <p>
	* 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.
	* </p>
	*
	* <p>
	* Example Builder:
	* <pre><code>
	* 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;
	* }
	* }
	* </code></pre>
	*
	* Example Builder Usage:
	* <pre><code>
	* Font bold14ptSansSerifFont = new FontBuilder(Font.SANS_SERIF).bold()
	* .size(14.0f)
	* .build();
	* </code></pre>
	*
	*
	* @param <T> the type of object that the builder will construct or compute.
	*
	* @since 3.0
	*/
	@FunctionalInterface
	public interface Builder<T> {

	/**
	* 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();
	}

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