001/*
002 * Licensed to the Apache Software Foundation (ASF) under one or more
003 * contributor license agreements.  See the NOTICE file distributed with
004 * this work for additional information regarding copyright ownership.
005 * The ASF licenses this file to You under the Apache License, Version 2.0
006 * (the "License"); you may not use this file except in compliance with
007 * the License.  You may obtain a copy of the License at
008 *
009 *      http://www.apache.org/licenses/LICENSE-2.0
010 *
011 * Unless required by applicable law or agreed to in writing, software
012 * distributed under the License is distributed on an "AS IS" BASIS,
013 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
014 * See the License for the specific language governing permissions and
015 * limitations under the License.
016 */
017package org.apache.juneau.rest.common.utils;
018
019import java.lang.reflect.*;
020
021/**
022 * HTTP utilities.
023 *
024 */
025public class HttpUtils {
026
027   // @formatter:off
028   private static final String[] 
029      LC_METHODS = { "get", "put", "post", "delete", "options", "head", "connect", "trace", "patch" },
030      UC_METHODS = { "GET", "PUT", "POST", "DELETE", "OPTIONS", "HEAD", "CONNECT", "TRACE", "PATCH" };
031   // @formatter:on
032
033   /**
034    * Given a method name, infers the REST method name.
035    *
036    * @param m The Java method.
037    * @param detectMethod Whether we should auto-detect the HTTP method name from the Java method name.
038    * @param def The default HTTP method if not detected.
039    * @return The REST method name, or the default value if not found.
040    */
041   public static String detectHttpMethod(Method m, boolean detectMethod, String def) {
042      String n = m.getName();
043      if (detectMethod) {
044         if (n.startsWith("do") && n.length() > 2) {
045            String n2 = n.substring(2).toUpperCase();
046            for (var t : UC_METHODS)
047               if (n2.equals(t))
048                  return n2;
049         }
050         for (var t : LC_METHODS)
051            if (n.startsWith(t) && (n.length() == t.length() || Character.isUpperCase(n.charAt(t.length()))))
052               return t.toUpperCase();
053      }
054      return def;
055   }
056
057   /**
058    * Given a Java method, infers the REST path.
059    *
060    * @param m The Java method.
061    * @param method The HTTP method name if it's known.
062    * @return The REST path or <jk>null</jk> if not detected.
063    */
064   public static String detectHttpPath(Method m, String method) {
065      String n = m.getName();
066      if (method == null) {
067         if (n.startsWith("do") && n.length() > 2) {
068            String n2 = n.substring(2).toUpperCase();
069            for (var t : UC_METHODS)
070               if (n2.equals(t))
071                  return "/";
072         }
073         for (var t : LC_METHODS) {
074            if (n.startsWith(t) && (n.length() == t.length() || Character.isUpperCase(n.charAt(t.length())))) {
075               return '/' + java.beans.Introspector.decapitalize(n.substring(t.length()));
076            }
077         }
078      } else {
079         if (n.equalsIgnoreCase(method) || n.equals("do") || n.equals("_"))
080            return "/";
081         if (n.startsWith(method) && (n.length() == method.length() || Character.isUpperCase(n.charAt(method.length())))) {
082            return '/' + java.beans.Introspector.decapitalize(n.substring(method.length()));
083         }
084      }
085      return '/' + n;
086   }
087}