| 1 | /** |
| 2 | * Licensed to jclouds, Inc. (jclouds) under one or more |
| 3 | * contributor license agreements. See the NOTICE file |
| 4 | * distributed with this work for additional information |
| 5 | * regarding copyright ownership. jclouds licenses this file |
| 6 | * to you under the Apache License, Version 2.0 (the |
| 7 | * "License"); you may not use this file except in compliance |
| 8 | * with the License. You may obtain a copy of the License at |
| 9 | * |
| 10 | * http://www.apache.org/licenses/LICENSE-2.0 |
| 11 | * |
| 12 | * Unless required by applicable law or agreed to in writing, |
| 13 | * software distributed under the License is distributed on an |
| 14 | * "AS IS" BASIS, WITHOUT WARRANTIES OR CONDITIONS OF ANY |
| 15 | * KIND, either express or implied. See the License for the |
| 16 | * specific language governing permissions and limitations |
| 17 | * under the License. |
| 18 | */ |
| 19 | package org.jclouds.blobstore.options; |
| 20 | |
| 21 | import static com.google.common.base.Preconditions.checkArgument; |
| 22 | import static com.google.common.base.Preconditions.checkNotNull; |
| 23 | |
| 24 | import java.io.UnsupportedEncodingException; |
| 25 | import java.util.ArrayList; |
| 26 | import java.util.Date; |
| 27 | import java.util.List; |
| 28 | |
| 29 | /** |
| 30 | * Contains options supported for HTTP GET operations. <h2> |
| 31 | * Usage</h2> The recommended way to instantiate a {@link GetOptions} object is to statically import |
| 32 | * GetOptions.Builder.* and invoke a static creation method followed by an instance mutator (if |
| 33 | * needed): |
| 34 | * <p/> |
| 35 | * <code> |
| 36 | * import static org.jclouds.blobstore.options.GetOptions.Builder.* |
| 37 | * |
| 38 | * |
| 39 | * // this will get the first megabyte of an blob, provided it wasn't modified since yesterday |
| 40 | * blob = blobStore.getBlob("container, "blobName",range(0,1024).ifUnmodifiedSince(new Date().minusDays(1))); |
| 41 | * <code> |
| 42 | * |
| 43 | * @author Adrian Cole |
| 44 | * |
| 45 | */ |
| 46 | public class GetOptions { |
| 47 | |
| 48 | public static final GetOptions NONE = new GetOptions(); |
| 49 | |
| 50 | private final List<String> ranges = new ArrayList<String>(); |
| 51 | private Date ifModifiedSince; |
| 52 | private Date ifUnmodifiedSince; |
| 53 | private String ifMatch; |
| 54 | private String ifNoneMatch; |
| 55 | |
| 56 | /** |
| 57 | * download the specified range of the object. |
| 58 | * @param start first offset included in the response |
| 59 | * @param end last offset included in the response (inclusive). |
| 60 | * @return itself to enable daisy-chaining of expressions |
| 61 | */ |
| 62 | public GetOptions range(long start, long end) { |
| 63 | checkArgument(start >= 0, "start must be >= 0"); |
| 64 | checkArgument(end >= 0, "end must be >= 0"); |
| 65 | getRanges().add(String.format("%d-%d", start, end)); |
| 66 | return this; |
| 67 | } |
| 68 | |
| 69 | /** |
| 70 | * download the specified range of the object. |
| 71 | */ |
| 72 | public GetOptions startAt(long start) { |
| 73 | checkArgument(start >= 0, "start must be >= 0"); |
| 74 | getRanges().add(String.format("%d-", start)); |
| 75 | return this; |
| 76 | } |
| 77 | |
| 78 | |
| 79 | /** |
| 80 | * download the specified range of the object starting from the end of the object. |
| 81 | */ |
| 82 | public GetOptions tail(long length) { |
| 83 | checkArgument(length >= 0, "length must be >= 0"); |
| 84 | getRanges().add(String.format("-%d", length)); |
| 85 | return this; |
| 86 | } |
| 87 | |
| 88 | /** |
| 89 | * Only return the object if it has changed since this time. |
| 90 | * <p /> |
| 91 | * Not compatible with {@link #ifETagMatches(String)} or {@link #ifUnmodifiedSince(Date)} |
| 92 | */ |
| 93 | public GetOptions ifModifiedSince(Date ifModifiedSince) { |
| 94 | checkArgument(getIfMatch() == null, "ifETagMatches() is not compatible with ifModifiedSince()"); |
| 95 | checkArgument(getIfUnmodifiedSince() == null, "ifUnmodifiedSince() is not compatible with ifModifiedSince()"); |
| 96 | this.ifModifiedSince = checkNotNull(ifModifiedSince, "ifModifiedSince"); |
| 97 | return this; |
| 98 | } |
| 99 | |
| 100 | /** |
| 101 | * For use in the header If-Modified-Since |
| 102 | * <p /> |
| 103 | * Return the object only if it has been modified since the specified time, otherwise return a |
| 104 | * 304 (not modified). |
| 105 | * |
| 106 | * @see GetOptions#ifModifiedSince(Date) |
| 107 | */ |
| 108 | public Date getIfModifiedSince() { |
| 109 | return this.ifModifiedSince; |
| 110 | } |
| 111 | |
| 112 | /** |
| 113 | * Only return the object if it hasn't changed since this time. |
| 114 | * <p /> |
| 115 | * Not compatible with {@link #ifETagDoesntMatch(String)} or {@link #ifModifiedSince(Date)} |
| 116 | */ |
| 117 | public GetOptions ifUnmodifiedSince(Date ifUnmodifiedSince) { |
| 118 | checkArgument(getIfNoneMatch() == null, "ifETagDoesntMatch() is not compatible with ifUnmodifiedSince()"); |
| 119 | checkArgument(getIfModifiedSince() == null, "ifModifiedSince() is not compatible with ifUnmodifiedSince()"); |
| 120 | this.ifUnmodifiedSince = checkNotNull(ifUnmodifiedSince, "ifUnmodifiedSince"); |
| 121 | return this; |
| 122 | } |
| 123 | |
| 124 | /** |
| 125 | * For use in the header If-Unmodified-Since |
| 126 | * <p /> |
| 127 | * Return the object only if it has not been modified since the specified time, otherwise return |
| 128 | * a 412 (precondition failed). |
| 129 | * |
| 130 | * @see GetOptions#ifUnmodifiedSince(Date) |
| 131 | */ |
| 132 | public Date getIfUnmodifiedSince() { |
| 133 | return this.ifUnmodifiedSince; |
| 134 | } |
| 135 | |
| 136 | /** |
| 137 | * The object's eTag hash should match the parameter <code>eTag</code>. |
| 138 | * |
| 139 | * <p /> |
| 140 | * Not compatible with {@link #ifETagDoesntMatch(String)} or {@link #ifModifiedSince(Date)} |
| 141 | * |
| 142 | * @param eTag |
| 143 | * hash representing the payload |
| 144 | */ |
| 145 | public GetOptions ifETagMatches(String eTag) { |
| 146 | checkArgument(getIfNoneMatch() == null, "ifETagDoesntMatch() is not compatible with ifETagMatches()"); |
| 147 | checkArgument(getIfModifiedSince() == null, "ifModifiedSince() is not compatible with ifETagMatches()"); |
| 148 | this.ifMatch = checkNotNull(eTag, "eTag"); |
| 149 | return this; |
| 150 | } |
| 151 | |
| 152 | /** |
| 153 | * For use in the request header: If-Match |
| 154 | * <p /> |
| 155 | * Return the object only if its payload tag (ETag) is the same as the eTag specified, otherwise |
| 156 | * return a 412 (precondition failed). |
| 157 | * |
| 158 | * @see GetOptions#ifETagMatches(String) |
| 159 | */ |
| 160 | public String getIfMatch() { |
| 161 | return this.ifMatch; |
| 162 | } |
| 163 | |
| 164 | /** |
| 165 | * The object should not have a eTag hash corresponding with the parameter <code>eTag</code>. |
| 166 | * <p /> |
| 167 | * Not compatible with {@link #ifETagMatches(String)} or {@link #ifUnmodifiedSince(Date)} |
| 168 | * |
| 169 | * @param eTag |
| 170 | * hash representing the payload |
| 171 | */ |
| 172 | public GetOptions ifETagDoesntMatch(String eTag) { |
| 173 | checkArgument(getIfMatch() == null, "ifETagMatches() is not compatible with ifETagDoesntMatch()"); |
| 174 | checkArgument(getIfUnmodifiedSince() == null, "ifUnmodifiedSince() is not compatible with ifETagDoesntMatch()"); |
| 175 | this.ifNoneMatch = checkNotNull(eTag, "eTag"); |
| 176 | return this; |
| 177 | } |
| 178 | |
| 179 | /** |
| 180 | * For use in the request header: If-None-Match |
| 181 | * <p /> |
| 182 | * Return the object only if its payload tag (ETag) is different from the one specified, |
| 183 | * otherwise return a 304 (not modified). |
| 184 | * |
| 185 | * @see GetOptions#ifETagDoesntMatch(String) |
| 186 | */ |
| 187 | public String getIfNoneMatch() { |
| 188 | return this.ifNoneMatch; |
| 189 | } |
| 190 | |
| 191 | public List<String> getRanges() { |
| 192 | return ranges; |
| 193 | } |
| 194 | |
| 195 | public static class Builder { |
| 196 | |
| 197 | /** |
| 198 | * @see GetOptions#range(long, long) |
| 199 | */ |
| 200 | public static GetOptions range(long start, long end) { |
| 201 | GetOptions options = new GetOptions(); |
| 202 | return options.range(start, end); |
| 203 | } |
| 204 | |
| 205 | /** |
| 206 | * @see GetOptions#getIfModifiedSince() |
| 207 | */ |
| 208 | public static GetOptions ifModifiedSince(Date ifModifiedSince) { |
| 209 | GetOptions options = new GetOptions(); |
| 210 | return options.ifModifiedSince(ifModifiedSince); |
| 211 | } |
| 212 | |
| 213 | /** |
| 214 | * @see GetOptions#ifUnmodifiedSince(Date) |
| 215 | */ |
| 216 | public static GetOptions ifUnmodifiedSince(Date ifUnmodifiedSince) { |
| 217 | GetOptions options = new GetOptions(); |
| 218 | return options.ifUnmodifiedSince(ifUnmodifiedSince); |
| 219 | } |
| 220 | |
| 221 | /** |
| 222 | * @see GetOptions#ifETagMatches(String) |
| 223 | */ |
| 224 | public static GetOptions ifETagMatches(String eTag) throws UnsupportedEncodingException { |
| 225 | GetOptions options = new GetOptions(); |
| 226 | return options.ifETagMatches(eTag); |
| 227 | } |
| 228 | |
| 229 | /** |
| 230 | * @see GetOptions#ifETagDoesntMatch(String) |
| 231 | */ |
| 232 | public static GetOptions ifETagDoesntMatch(String eTag) throws UnsupportedEncodingException { |
| 233 | GetOptions options = new GetOptions(); |
| 234 | return options.ifETagDoesntMatch(eTag); |
| 235 | } |
| 236 | |
| 237 | } |
| 238 | |
| 239 | @Override |
| 240 | public int hashCode() { |
| 241 | final int prime = 31; |
| 242 | int result = 1; |
| 243 | result = prime * result + ((ifMatch == null) ? 0 : ifMatch.hashCode()); |
| 244 | result = prime * result + ((ifModifiedSince == null) ? 0 : ifModifiedSince.hashCode()); |
| 245 | result = prime * result + ((ifNoneMatch == null) ? 0 : ifNoneMatch.hashCode()); |
| 246 | result = prime * result + ((ifUnmodifiedSince == null) ? 0 : ifUnmodifiedSince.hashCode()); |
| 247 | result = prime * result + ((ranges == null) ? 0 : ranges.hashCode()); |
| 248 | return result; |
| 249 | } |
| 250 | |
| 251 | @Override |
| 252 | public boolean equals(Object obj) { |
| 253 | if (this == obj) |
| 254 | return true; |
| 255 | if (obj == null) |
| 256 | return false; |
| 257 | if (getClass() != obj.getClass()) |
| 258 | return false; |
| 259 | GetOptions other = (GetOptions) obj; |
| 260 | if (ifMatch == null) { |
| 261 | if (other.ifMatch != null) |
| 262 | return false; |
| 263 | } else if (!ifMatch.equals(other.ifMatch)) |
| 264 | return false; |
| 265 | if (ifModifiedSince == null) { |
| 266 | if (other.ifModifiedSince != null) |
| 267 | return false; |
| 268 | } else if (!ifModifiedSince.equals(other.ifModifiedSince)) |
| 269 | return false; |
| 270 | if (ifNoneMatch == null) { |
| 271 | if (other.ifNoneMatch != null) |
| 272 | return false; |
| 273 | } else if (!ifNoneMatch.equals(other.ifNoneMatch)) |
| 274 | return false; |
| 275 | if (ifUnmodifiedSince == null) { |
| 276 | if (other.ifUnmodifiedSince != null) |
| 277 | return false; |
| 278 | } else if (!ifUnmodifiedSince.equals(other.ifUnmodifiedSince)) |
| 279 | return false; |
| 280 | if (ranges == null) { |
| 281 | if (other.ranges != null) |
| 282 | return false; |
| 283 | } else if (!ranges.equals(other.ranges)) |
| 284 | return false; |
| 285 | return true; |
| 286 | } |
| 287 | |
| 288 | @Override |
| 289 | public String toString() { |
| 290 | return "[ranges=" + ranges + ", ifModifiedSince=" + ifModifiedSince + ", ifUnmodifiedSince=" + ifUnmodifiedSince |
| 291 | + ", ifMatch=" + ifMatch + ", ifNoneMatch=" + ifNoneMatch + "]"; |
| 292 | } |
| 293 | |
| 294 | } |