001 /**
002 * Licensed to the Apache Software Foundation (ASF) under one
003 * or more contributor license agreements. See the NOTICE file
004 * distributed with this work for additional information
005 * regarding copyright ownership. The ASF licenses this file
006 * to you under the Apache License, Version 2.0 (the
007 * "License"); you may not use this file except in compliance
008 * with the License. You may obtain a copy of the License at
009 *
010 * http://www.apache.org/licenses/LICENSE-2.0
011 *
012 * Unless required by applicable law or agreed to in writing, software
013 * distributed under the License is distributed on an "AS IS" BASIS,
014 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
015 * See the License for the specific language governing permissions and
016 * limitations under the License.
017 */
018
019 package org.apache.hadoop.lib.wsrs;
020
021 import com.google.common.collect.Lists;
022 import com.sun.jersey.api.core.HttpContext;
023 import com.sun.jersey.core.spi.component.ComponentContext;
024 import com.sun.jersey.core.spi.component.ComponentScope;
025 import com.sun.jersey.server.impl.inject.AbstractHttpContextInjectable;
026 import com.sun.jersey.spi.inject.Injectable;
027 import com.sun.jersey.spi.inject.InjectableProvider;
028 import org.apache.hadoop.classification.InterfaceAudience;
029
030 import javax.ws.rs.core.Context;
031 import javax.ws.rs.core.MultivaluedMap;
032 import java.lang.reflect.Type;
033 import java.text.MessageFormat;
034 import java.util.HashMap;
035 import java.util.List;
036 import java.util.Map;
037
038 /**
039 * Jersey provider that parses the request parameters based on the
040 * given parameter definition.
041 */
042 @InterfaceAudience.Private
043 public class ParametersProvider
044 extends AbstractHttpContextInjectable<Parameters>
045 implements InjectableProvider<Context, Type> {
046
047 private String driverParam;
048 private Class<? extends Enum> enumClass;
049 private Map<Enum, Class<Param<?>>[]> paramsDef;
050
051 public ParametersProvider(String driverParam, Class<? extends Enum> enumClass,
052 Map<Enum, Class<Param<?>>[]> paramsDef) {
053 this.driverParam = driverParam;
054 this.enumClass = enumClass;
055 this.paramsDef = paramsDef;
056 }
057
058 @Override
059 @SuppressWarnings("unchecked")
060 public Parameters getValue(HttpContext httpContext) {
061 Map<String, List<Param<?>>> map = new HashMap<String, List<Param<?>>>();
062 Map<String, List<String>> queryString =
063 httpContext.getRequest().getQueryParameters();
064 String str = ((MultivaluedMap<String, String>) queryString).
065 getFirst(driverParam);
066 if (str == null) {
067 throw new IllegalArgumentException(
068 MessageFormat.format("Missing Operation parameter [{0}]",
069 driverParam));
070 }
071 Enum op;
072 try {
073 op = Enum.valueOf(enumClass, str.toUpperCase());
074 } catch (IllegalArgumentException ex) {
075 throw new IllegalArgumentException(
076 MessageFormat.format("Invalid Operation [{0}]", str));
077 }
078 if (!paramsDef.containsKey(op)) {
079 throw new IllegalArgumentException(
080 MessageFormat.format("Unsupported Operation [{0}]", op));
081 }
082 for (Class<Param<?>> paramClass : paramsDef.get(op)) {
083 Param<?> param = newParam(paramClass);
084 List<Param<?>> paramList = Lists.newArrayList();
085 List<String> ps = queryString.get(param.getName());
086 if (ps != null) {
087 for (String p : ps) {
088 try {
089 param.parseParam(p);
090 }
091 catch (Exception ex) {
092 throw new IllegalArgumentException(ex.toString(), ex);
093 }
094 paramList.add(param);
095 param = newParam(paramClass);
096 }
097 } else {
098 paramList.add(param);
099 }
100
101 map.put(param.getName(), paramList);
102 }
103 return new Parameters(map);
104 }
105
106 private Param<?> newParam(Class<Param<?>> paramClass) {
107 try {
108 return paramClass.newInstance();
109 } catch (Exception ex) {
110 throw new UnsupportedOperationException(
111 MessageFormat.format(
112 "Param class [{0}] does not have default constructor",
113 paramClass.getName()));
114 }
115 }
116
117 @Override
118 public ComponentScope getScope() {
119 return ComponentScope.PerRequest;
120 }
121
122 @Override
123 public Injectable getInjectable(ComponentContext componentContext, Context context, Type type) {
124 return (type.equals(Parameters.class)) ? this : null;
125 }
126 }