juneau-rest/juneau-rest-server/src/main/java/org/apache/juneau/rest/DebugEnablementBuilder.java

// ***************************************************************************************************************************
// * 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.juneau.rest;

import static org.apache.juneau.internal.ClassUtils.*;
import static org.apache.juneau.rest.HttpRuntimeException.*;
import static org.apache.juneau.Enablement.*;

import java.util.function.*;

import javax.servlet.http.*;

import org.apache.juneau.*;
import org.apache.juneau.cp.*;
import org.apache.juneau.http.response.*;
import org.apache.juneau.utils.*;

/**
 * Builder for {@link DebugEnablement} objects.
 */
public class DebugEnablementBuilder {

	ReflectionMapBuilder<Enablement> mapBuilder = new ReflectionMapBuilder<>();
	private Class<? extends DebugEnablement> implClass;
	Enablement defaultEnablement = NEVER;
	BeanStore beanStore;
	Predicate<HttpServletRequest> conditionalPredicate = x -> "true".equalsIgnoreCase(x.getHeader("Debug"));

	/**
	 * Creates a new {@link DebugEnablement} object from this builder.
	 *s
	 * <p>
	 * Instantiates an instance of the {@link #implClass(Class) implementation class} or
	 * else {@link BasicDebugEnablement} if implementation class was not specified.
	 *
	 * @return A new {@link DebugEnablement} object.
	 */
	public DebugEnablement build() {
		try {
			Class<? extends DebugEnablement> ic = isConcrete(implClass) ? implClass : getDefaultImplClass();
			return BeanStore.of(beanStore).addBeans(DebugEnablementBuilder.class, this).createBean(ic);
		} catch (Exception e) {
			throw toHttpException(e, InternalServerError.class);
		}
	}

	/**
	 * Specifies the default implementation class if not specified via {@link #implClass(Class)}.
	 *
	 * @return The default implementation class if not specified via {@link #implClass(Class)}.
	 */
	protected Class<? extends DebugEnablement> getDefaultImplClass() {
		return BasicDebugEnablement.class;
	}

	/**
	 * Specifies the bean store to use for instantiating the {@link DebugEnablement} object.
	 *
	 * @param value The new value for this setting.
	 * @return  This object (for method chaining).
	 */
	public DebugEnablementBuilder beanStore(BeanStore value) {
		this.beanStore = value;
		return this;
	}

	/**
	 * Specifies a subclass of {@link DebugEnablement} to create when the {@link #build()} method is called.
	 *
	 * @param value The new value for this setting.
	 * @return  This object (for method chaining).
	 */
	public DebugEnablementBuilder implClass(Class<? extends DebugEnablement> value) {
		this.implClass = value;
		return this;
	}

	/**
	 * Enables or disables debug on the specified classes and/or methods.
	 *
	 * <p>
	 * Allows you to target specified debug enablement on specified classes and/or methods.
	 *
	 * @param enablement
	 * 	The debug enablement setting to set on the specified classes/methods.
	 * 	<br>Can be any of the following:
	 * 	<ul>
	 * 		<li>{@link Enablement#ALWAYS ALWAYS} - Debug is always enabled.
	 * 		<li>{@link Enablement#NEVER NEVER} - Debug is always disabled.
	 * 		<li>{@link Enablement#CONDITIONAL CONDITIONAL} - Debug is enabled when the {@link #conditionalPredicate(Predicate)} conditional predicate test} passes.
	 * 	</ul>
	 * @param keys
	 * 	The mapping keys.
	 * 	<br>Can be any of the following:
	 * 	<ul>
	 * 		<li>Full class name (e.g. <js>"com.foo.MyClass"</js>).
	 * 		<li>Simple class name (e.g. <js>"MyClass"</js>).
	 * 		<li>All classes (e.g. <js>"*"</js>).
	 * 		<li>Full method name (e.g. <js>"com.foo.MyClass.myMethod"</js>).
	 * 		<li>Simple method name (e.g. <js>"MyClass.myMethod"</js>).
	 * 		<li>A comma-delimited list of anything on this list.
	 * 	</ul>
	 * @return This object (for method chaining).
	 */
	public DebugEnablementBuilder enable(Enablement enablement, String...keys) {
		for (String k : keys)
			mapBuilder.append(k, enablement);
		return this;
	}

	/**
	 * Enables or disables debug on the specified classes.
	 *
	 * <p>
	 * Identical to {@link #enable(Enablement, String...)} but allows you to specify specific classes.
	 *
	 * @param enablement
	 * 	The debug enablement setting to set on the specified classes/methods.
	 * 	<br>Can be any of the following:
	 * 	<ul>
	 * 		<li>{@link Enablement#ALWAYS ALWAYS} - Debug is always enabled.
	 * 		<li>{@link Enablement#NEVER NEVER} - Debug is always disabled.
	 * 		<li>{@link Enablement#CONDITIONAL CONDITIONAL} - Debug is enabled when the {@link #conditionalPredicate(Predicate)} conditional predicate test} passes.
	 * 	</ul>
	 * @param classes
	 * 	The classes to set the debug enablement setting on.
	 * @return This object (for method chaining).
	 */
	public DebugEnablementBuilder enable(Enablement enablement, Class<?>...classes) {
		for (Class<?> c : classes)
			mapBuilder.append(c.getName(), enablement);
		return this;
	}

	/**
	 * Specifies the default debug enablement setting if not overridden per class/method.
	 *
	 * <p>
	 * The default value for this setting is {@link Enablement#NEVER NEVER}.
	 *
	 * @param value The default debug enablement setting if not overridden per class/method.
	 * @return This object (for method chaining).
	 */
	public DebugEnablementBuilder defaultEnable(Enablement value) {
		this.defaultEnablement = value;
		return this;
	}

	/**
	 * Specifies the predicate to use for conditional debug enablement.
	 *
	 * <p>
	 * Specifies the predicate to use to determine whether debug is enabled when the resolved enablement value
	 * is {@link Enablement#CONDITIONAL CONDITIONAL}.
	 *
	 * <p>
	 * The default value for this setting is <c>(<jv>x</jv>)-><js>"true"</js>.equalsIgnoreCase(<jv>x</jv>.getHeader(<js>"Debug"</js>))</c>.
	 *
	 * @param value The predicate.
	 * @return This object (for method chaining).
	 */
	public DebugEnablementBuilder conditionalPredicate(Predicate<HttpServletRequest> value) {
		this.conditionalPredicate = value;
		return this;
	}
}