001/* 002 * ==================================================================== 003 * Licensed to the Apache Software Foundation (ASF) under one 004 * or more contributor license agreements. See the NOTICE file 005 * distributed with this work for additional information 006 * regarding copyright ownership. The ASF licenses this file 007 * to you under the Apache License, Version 2.0 (the 008 * "License"); you may not use this file except in compliance 009 * with the License. You may obtain a copy of the License at 010 * 011 * http://www.apache.org/licenses/LICENSE-2.0 012 * 013 * Unless required by applicable law or agreed to in writing, 014 * software distributed under the License is distributed on an 015 * "AS IS" BASIS, WITHOUT WARRANTIES OR CONDITIONS OF ANY 016 * KIND, either express or implied. See the License for the 017 * specific language governing permissions and limitations 018 * under the License. 019 * ==================================================================== 020 * 021 * This software consists of voluntary contributions made by many 022 * individuals on behalf of the Apache Software Foundation. For more 023 * information on the Apache Software Foundation, please see 024 * <http://www.apache.org/>. 025 * 026 */ 027 028package org.apache.http.protocol; 029 030import java.util.Map; 031import java.util.concurrent.ConcurrentHashMap; 032 033import org.apache.http.annotation.ThreadingBehavior; 034import org.apache.http.annotation.Contract; 035import org.apache.http.util.Args; 036 037/** 038 * Default implementation of {@link HttpContext}. 039 * <p> 040 * Please note instances of this class can be thread unsafe if the 041 * parent context is not thread safe. 042 * 043 * @since 4.0 044 */ 045@Contract(threading = ThreadingBehavior.SAFE_CONDITIONAL) 046public class BasicHttpContext implements HttpContext { 047 048 private final HttpContext parentContext; 049 private final Map<String, Object> map; 050 051 public BasicHttpContext() { 052 this(null); 053 } 054 055 public BasicHttpContext(final HttpContext parentContext) { 056 super(); 057 this.map = new ConcurrentHashMap<String, Object>(); 058 this.parentContext = parentContext; 059 } 060 061 @Override 062 public Object getAttribute(final String id) { 063 Args.notNull(id, "Id"); 064 Object obj = this.map.get(id); 065 if (obj == null && this.parentContext != null) { 066 obj = this.parentContext.getAttribute(id); 067 } 068 return obj; 069 } 070 071 @Override 072 public void setAttribute(final String id, final Object obj) { 073 Args.notNull(id, "Id"); 074 if (obj != null) { 075 this.map.put(id, obj); 076 } else { 077 this.map.remove(id); 078 } 079 } 080 081 @Override 082 public Object removeAttribute(final String id) { 083 Args.notNull(id, "Id"); 084 return this.map.remove(id); 085 } 086 087 /** 088 * @since 4.2 089 */ 090 public void clear() { 091 this.map.clear(); 092 } 093 094 @Override 095 public String toString() { 096 return this.map.toString(); 097 } 098 099}